summaryrefslogtreecommitdiff
path: root/include
AgeCommit message (Collapse)AuthorFilesLines
2019-07-31clocksource/drivers/exynos_mct: Increase priority over ARM arch timerMarek Szyprowski1-1/+1
[ Upstream commit 6282edb72bed5324352522d732080d4c1b9dfed6 ] Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT (Multi Core Timer) and standard ARM Architected Timers. There are use cases, where both timer interfaces are used simultanously. One of such examples is using Exynos MCT for the main system timer and ARM Architected Timers for the KVM and virtualized guests (KVM requires arch timers). Exynos Multi-Core Timer driver (exynos_mct) must be however started before ARM Architected Timers (arch_timer), because they both share some common hardware blocks (global system counter) and turning on MCT is needed to get ARM Architected Timer working properly. To ensure selecting Exynos MCT as the main system timer, increase MCT timer rating. To ensure proper starting order of both timers during suspend/resume cycle, increase MCT hotplug priority over ARM Archictected Timers. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31ipvs: fix tinfo memory leak in start_sync_threadJulian Anastasov1-2/+4
[ Upstream commit 5db7c8b9f9fc2aeec671ae3ca6375752c162e0e7 ] syzkaller reports for memory leak in start_sync_thread [1] As Eric points out, kthread may start and stop before the threadfn function is called, so there is no chance the data (tinfo in our case) to be released in thread. Fix this by releasing tinfo in the controlling code instead. [1] BUG: memory leak unreferenced object 0xffff8881206bf700 (size 32): comm "syz-executor761", pid 7268, jiffies 4294943441 (age 20.470s) hex dump (first 32 bytes): 00 40 7c 09 81 88 ff ff 80 45 b8 21 81 88 ff ff .@|......E.!.... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000057619e23>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<0000000057619e23>] slab_post_alloc_hook mm/slab.h:439 [inline] [<0000000057619e23>] slab_alloc mm/slab.c:3326 [inline] [<0000000057619e23>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<0000000086ce5479>] kmalloc include/linux/slab.h:547 [inline] [<0000000086ce5479>] start_sync_thread+0x5d2/0xe10 net/netfilter/ipvs/ip_vs_sync.c:1862 [<000000001a9229cc>] do_ip_vs_set_ctl+0x4c5/0x780 net/netfilter/ipvs/ip_vs_ctl.c:2402 [<00000000ece457c8>] nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] [<00000000ece457c8>] nf_setsockopt+0x4c/0x80 net/netfilter/nf_sockopt.c:115 [<00000000942f62d4>] ip_setsockopt net/ipv4/ip_sockglue.c:1258 [inline] [<00000000942f62d4>] ip_setsockopt+0x9b/0xb0 net/ipv4/ip_sockglue.c:1238 [<00000000a56a8ffd>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<00000000fa895401>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000095eef4cf>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<000000009747cf88>] __do_sys_setsockopt net/socket.c:2089 [inline] [<000000009747cf88>] __se_sys_setsockopt net/socket.c:2086 [inline] [<000000009747cf88>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<00000000ded8ba80>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000893b4ac8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported-by: syzbot+7e2e50c8adfccd2e5041@syzkaller.appspotmail.com Suggested-by: Eric Biggers <ebiggers@kernel.org> Fixes: 998e7a76804b ("ipvs: Use kthread_run() instead of doing a double-fork via kernel_thread()") Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31rcu: Force inlining of rcu_read_lock()Waiman Long1-1/+1
[ Upstream commit 6da9f775175e516fc7229ceaa9b54f8f56aa7924 ] When debugging options are turned on, the rcu_read_lock() function might not be inlined. This results in lockdep's print_lock() function printing "rcu_read_lock+0x0/0x70" instead of rcu_read_lock()'s caller. For example: [ 10.579995] ============================= [ 10.584033] WARNING: suspicious RCU usage [ 10.588074] 4.18.0.memcg_v2+ #1 Not tainted [ 10.593162] ----------------------------- [ 10.597203] include/linux/rcupdate.h:281 Illegal context switch in RCU read-side critical section! [ 10.606220] [ 10.606220] other info that might help us debug this: [ 10.606220] [ 10.614280] [ 10.614280] rcu_scheduler_active = 2, debug_locks = 1 [ 10.620853] 3 locks held by systemd/1: [ 10.624632] #0: (____ptrval____) (&type->i_mutex_dir_key#5){.+.+}, at: lookup_slow+0x42/0x70 [ 10.633232] #1: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70 [ 10.640954] #2: (____ptrval____) (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70 These "rcu_read_lock+0x0/0x70" strings are not providing any useful information. This commit therefore forces inlining of the rcu_read_lock() function so that rcu_read_lock()'s caller is instead shown. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21linux/kernel.h: fix overflow for DIV_ROUND_UP_ULLVinod Koul1-1/+2
[ Upstream commit 8f9fab480c7a87b10bb5440b5555f370272a5d59 ] DIV_ROUND_UP_ULL adds the two arguments and then invokes DIV_ROUND_DOWN_ULL. But on a 32bit system the addition of two 32 bit values can overflow. DIV_ROUND_DOWN_ULL does it correctly and stashes the addition into a unsigned long long so cast the result to unsigned long long here to avoid the overflow condition. [akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval] Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org Signed-off-by: Vinod Koul <vkoul@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21VMCI: Fix integer overflow in VMCI handle arraysVishnu DASA1-1/+10
commit 1c2eb5b2853c9f513690ba6b71072d8eb65da16a upstream. The VMCI handle array has an integer overflow in vmci_handle_arr_append_entry when it tries to expand the array. This can be triggered from a guest, since the doorbell link hypercall doesn't impose a limit on the number of doorbell handles that a VM can create in the hypervisor, and these handles are stored in a handle array. In this change, we introduce a mandatory max capacity for handle arrays/lists to avoid excessive memory usage. Signed-off-by: Vishnu Dasa <vdasa@vmware.com> Reviewed-by: Adit Ranadive <aditr@vmware.com> Reviewed-by: Jorgen Hansen <jhansen@vmware.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-21ip6_tunnel: allow not to count pkts on tstats by passing dev as NULLXin Long1-3/+6
[ Upstream commit 6f6a8622057c92408930c31698394fae1557b188 ] A similar fix to Patch "ip_tunnel: allow not to count pkts on tstats by setting skb's dev to NULL" is also needed by ip6_tunnel. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDTJames Morse1-0/+1
commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream. The cacheinfo structures are alloced/freed by cpu online/offline callbacks. Originally these were only used by sysfs to expose the cache topology to user space. Without any in-kernel dependencies CPUHP_AP_ONLINE_DYN was an appropriate choice. resctrl has started using these structures to identify CPUs that share a cache. It updates its 'domain' structures from cpu online/offline callbacks. These depend on the cacheinfo structures (resctrl_online_cpu()->domain_add_cpu()->get_cache_id()-> get_cpu_cacheinfo()). These also run as CPUHP_AP_ONLINE_DYN. Now that there is an in-kernel dependency, move the cacheinfo work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN work runs. Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology") Cc: <stable@vger.kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: James Morse <james.morse@arm.com> Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-21nilfs2: do not use unexported cpu_to_le32()/le32_to_cpu() in uapi headerMasahiro Yamada1-12/+12
commit c32cc30c0544f13982ee0185d55f4910319b1a79 upstream. cpu_to_le32/le32_to_cpu is defined in include/linux/byteorder/generic.h, which is not exported to user-space. UAPI headers must use the ones prefixed with double-underscore. Detected by compile-testing exported headers: include/linux/nilfs2_ondisk.h: In function `nilfs_checkpoint_set_snapshot': include/linux/nilfs2_ondisk.h:536:17: error: implicit declaration of function `cpu_to_le32' [-Werror=implicit-function-declaration] cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) | \ ^ include/linux/nilfs2_ondisk.h:552:1: note: in expansion of macro `NILFS_CHECKPOINT_FNS' NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot) ^~~~~~~~~~~~~~~~~~~~ include/linux/nilfs2_ondisk.h:536:29: error: implicit declaration of function `le32_to_cpu' [-Werror=implicit-function-declaration] cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) | \ ^ include/linux/nilfs2_ondisk.h:552:1: note: in expansion of macro `NILFS_CHECKPOINT_FNS' NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot) ^~~~~~~~~~~~~~~~~~~~ include/linux/nilfs2_ondisk.h: In function `nilfs_segment_usage_set_clean': include/linux/nilfs2_ondisk.h:622:19: error: implicit declaration of function `cpu_to_le64' [-Werror=implicit-function-declaration] su->su_lastmod = cpu_to_le64(0); ^~~~~~~~~~~ Link: http://lkml.kernel.org/r/20190605053006.14332-1-yamada.masahiro@socionext.com Fixes: e63e88bc53ba ("nilfs2: move ioctl interface and disk layout to uapi separately") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Joe Perches <joe@perches.com> Cc: <stable@vger.kernel.org> [4.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03futex: Update comments and docs about return values of arch futex codeWill Deacon1-2/+6
commit 427503519739e779c0db8afe876c1b33f3ac60ae upstream. The architecture implementations of 'arch_futex_atomic_op_inuser()' and 'futex_atomic_cmpxchg_inatomic()' are permitted to return only -EFAULT, -EAGAIN or -ENOSYS in the case of failure. Update the comments in the asm-generic/ implementation and also a stray reference in the robust futex documentation. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03Revert "compiler.h: update definition of unreachable()"Sasha Levin1-4/+1
This reverts commit 82017e26e51596ee577171a33f357377ec6513b5, which is upstream commit fe0640eb30b7da261ae84d252ed9ed3c7e68dfd8. On Fri, Jun 28, 2019 at 8:53 AM Tony Battersby <tonyb@cybernetics.com> wrote: > > Old versions of gcc cannot compile 4.14 since 4.14.113: > > ./include/asm-generic/fixmap.h:37: error: implicit declaration of function ‘__builtin_unreachable’ > > The stable commit that caused the problem is 82017e26e515 ("compiler.h: > update definition of unreachable()") (upstream commit fe0640eb30b7). > Reverting the commit fixes the problem. > > Kernel 4.17 dropped support for older versions of gcc in upstream commit > cafa0010cd51 ("Raise the minimum required gcc version to 4.6"). This > was not backported to 4.14 since that would go against the stable kernel > rules. > > Upstream commit 815f0ddb346c ("include/linux/compiler*.h: make > compiler-*.h mutually exclusive") was a fix for cafa0010cd51. This was > not backported to 4.14. > > Upstream commit fe0640eb30b7 ("compiler.h: update definition of > unreachable()") was a fix for 815f0ddb346c. This is the commit that was > backported to 4.14. But it only fixed a problem introduced in the other > commits, and without those commits, it ends up introducing a problem > instead of fixing one. So I recommend reverting that patch in 4.14, > which will enable old gcc to compile 4.14 again. If I understand > correctly, I believe that clang will still be able to compile 4.14 with > the patch reverted, although I haven't tried to compile with clang. > > The problematic commit is not present in 4.9.x, 4.4.x, 3.18.x, or 3.16.x. CC: Nick Desaulniers <ndesaulniers@google.com> CC: Tony Battersby <tonyb@cybernetics.com>, Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-03block: add a lower-level bio_add_page interfaceChristoph Hellwig1-0/+9
[ Upstream commit 0aa69fd32a5f766e997ca8ab4723c5a1146efa8b ] For the upcoming removal of buffer heads in XFS we need to keep track of the number of outstanding writeback requests per page. For this we need to know if bio_add_page merged a region with the previous bvec or not. Instead of adding additional arguments this refactors bio_add_page to be implemented using three lower level helpers which users like XFS can use directly if they care about the merge decisions. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-25Bluetooth: Align minimum encryption key size for LE and BR/EDR connectionsMarcel Holtmann1-0/+3
commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream. The minimum encryption key size for LE connections is 56 bits and to align LE with BR/EDR, enforce 56 bits of minimum encryption key size for BR/EDR connections as well. Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-22coredump: fix race condition between collapse_huge_page() and core dumpingAndrea Arcangeli1-0/+4
commit 59ea6d06cfa9247b586a695c21f94afa7183af74 upstream. When fixing the race conditions between the coredump and the mmap_sem holders outside the context of the process, we focused on mmget_not_zero()/get_task_mm() callers in 04f5866e41fb70 ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping"), but those aren't the only cases where the mmap_sem can be taken outside of the context of the process as Michal Hocko noticed while backporting that commit to older -stable kernels. If mmgrab() is called in the context of the process, but then the mm_count reference is transferred outside the context of the process, that can also be a problem if the mmap_sem has to be taken for writing through that mm_count reference. khugepaged registration calls mmgrab() in the context of the process, but the mmap_sem for writing is taken later in the context of the khugepaged kernel thread. collapse_huge_page() after taking the mmap_sem for writing doesn't modify any vma, so it's not obvious that it could cause a problem to the coredump, but it happens to modify the pmd in a way that breaks an invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page() needs the mmap_sem for writing just to block concurrent page faults that call pmd_trans_huge_lock(). Specifically the invariant that "!pmd_trans_huge()" cannot become a "pmd_trans_huge()" doesn't hold while collapse_huge_page() runs. The coredump will call __get_user_pages() without mmap_sem for reading, which eventually can invoke a lockless page fault which will need a functional pmd_trans_huge_lock(). So collapse_huge_page() needs to use mmget_still_valid() to check it's not running concurrently with the coredump... as long as the coredump can invoke page faults without holding the mmap_sem for reading. This has "Fixes: khugepaged" to facilitate backporting, but in my view it's more a bug in the coredump code that will eventually have to be rewritten to stop invoking page faults without the mmap_sem for reading. So the long term plan is still to drop all mmget_still_valid(). Link: http://lkml.kernel.org/r/20190607161558.32104-1-aarcange@redhat.com Fixes: ba76149f47d8 ("thp: khugepaged") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Peter Xu <peterx@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19x86/microcode, cpuhotplug: Add a microcode loader CPU hotplug callbackBorislav Petkov1-0/+1
commit 78f4e932f7760d965fb1569025d1576ab77557c5 upstream. Adric Blake reported the following warning during suspend-resume: Enabling non-boot CPUs ... x86: Booting SMP configuration: smpboot: Booting Node 0 Processor 1 APIC 0x2 unchecked MSR access error: WRMSR to 0x10f (tried to write 0x0000000000000000) \ at rIP: 0xffffffff8d267924 (native_write_msr+0x4/0x20) Call Trace: intel_set_tfa intel_pmu_cpu_starting ? x86_pmu_dead_cpu x86_pmu_starting_cpu cpuhp_invoke_callback ? _raw_spin_lock_irqsave notify_cpu_starting start_secondary secondary_startup_64 microcode: sig=0x806ea, pf=0x80, revision=0x96 microcode: updated to revision 0xb4, date = 2019-04-01 CPU1 is up The MSR in question is MSR_TFA_RTM_FORCE_ABORT and that MSR is emulated by microcode. The log above shows that the microcode loader callback happens after the PMU restoration, leading to the conjecture that because the microcode hasn't been updated yet, that MSR is not present yet, leading to the #GP. Add a microcode loader-specific hotplug vector which comes before the PERF vectors and thus executes earlier and makes sure the MSR is present. Fixes: 400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort") Reported-by: Adric Blake <promarbler14@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: x86@kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=203637 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19cgroup: Use css_tryget() instead of css_tryget_online() in task_get_css()Tejun Heo1-2/+8
commit 18fa84a2db0e15b02baa5d94bdb5bd509175d2f6 upstream. A PF_EXITING task can stay associated with an offline css. If such task calls task_get_css(), it can get stuck indefinitely. This can be triggered by BSD process accounting which writes to a file with PF_EXITING set when racing against memcg disable as in the backtrace at the end. After this change, task_get_css() may return a css which was already offline when the function was called. None of the existing users are affected by this change. INFO: rcu_sched self-detected stall on CPU INFO: rcu_sched detected stalls on CPUs/tasks: ... NMI backtrace for cpu 0 ... Call Trace: <IRQ> dump_stack+0x46/0x68 nmi_cpu_backtrace.cold.2+0x13/0x57 nmi_trigger_cpumask_backtrace+0xba/0xca rcu_dump_cpu_stacks+0x9e/0xce rcu_check_callbacks.cold.74+0x2af/0x433 update_process_times+0x28/0x60 tick_sched_timer+0x34/0x70 __hrtimer_run_queues+0xee/0x250 hrtimer_interrupt+0xf4/0x210 smp_apic_timer_interrupt+0x56/0x110 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0010:balance_dirty_pages_ratelimited+0x28f/0x3d0 ... btrfs_file_write_iter+0x31b/0x563 __vfs_write+0xfa/0x140 __kernel_write+0x4f/0x100 do_acct_process+0x495/0x580 acct_process+0xb9/0xdb do_exit+0x748/0xa00 do_group_exit+0x3a/0xa0 get_signal+0x254/0x560 do_signal+0x23/0x5c0 exit_to_usermode_loop+0x5d/0xa0 prepare_exit_to_usermode+0x53/0x80 retint_user+0x8/0x8 Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org # v4.2+ Fixes: ec438699a9ae ("cgroup, block: implement task_get_css() and use it in bio_associate_current()") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-17tcp: add tcp_min_snd_mss sysctlEric Dumazet1-0/+1
commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream. Some TCP peers announce a very small MSS option in their SYN and/or SYN/ACK messages. This forces the stack to send packets with a very high network/cpu overhead. Linux has enforced a minimal value of 48. Since this value includes the size of TCP options, and that the options can consume up to 40 bytes, this means that each segment can include only 8 bytes of payload. In some cases, it can be useful to increase the minimal value to a saner value. We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility reasons. Note that TCP_MAXSEG socket option enforces a minimal value of (TCP_MIN_MSS). David Miller increased this minimal value in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.") from 64 to 88. We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-17tcp: tcp_fragment() should apply sane memory limitsEric Dumazet1-0/+1
commit f070ef2ac66716357066b683fb0baf55f8191a2e upstream. Jonathan Looney reported that a malicious peer can force a sender to fragment its retransmit queue into tiny skbs, inflating memory usage and/or overflow 32bit counters. TCP allows an application to queue up to sk_sndbuf bytes, so we need to give some allowance for non malicious splitting of retransmit queue. A new SNMP counter is added to monitor how many times TCP did not allow to split an skb if the allowance was exceeded. Note that this counter might increase in the case applications use SO_SNDBUF socket option to lower sk_sndbuf. CVE-2019-11478 : tcp_fragment, prevent fragmenting a packet when the socket is already using more than half the allowed space Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-17tcp: limit payload size of sacked skbsEric Dumazet2-0/+6
commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff upstream. Jonathan Looney reported that TCP can trigger the following crash in tcp_shifted_skb() : BUG_ON(tcp_skb_pcount(skb) < pcount); This can happen if the remote peer has advertized the smallest MSS that linux TCP accepts : 48 An skb can hold 17 fragments, and each fragment can hold 32KB on x86, or 64KB on PowerPC. This means that the 16bit witdh of TCP_SKB_CB(skb)->tcp_gso_segs can overflow. Note that tcp_sendmsg() builds skbs with less than 64KB of payload, so this problem needs SACK to be enabled. SACK blocks allow TCP to coalesce multiple skbs in the retransmit queue, thus filling the 17 fragments to maximal capacity. CVE-2019-11477 -- u16 overflow of TCP_SKB_CB(skb)->tcp_gso_segs Backport notes, provided by Joao Martins <joao.m.martins@oracle.com> v4.15 or since commit 737ff314563 ("tcp: use sequence distance to detect reordering") had switched from the packet-based FACK tracking and switched to sequence-based. v4.14 and older still have the old logic and hence on tcp_skb_shift_data() needs to retain its original logic and have @fack_count in sync. In other words, we keep the increment of pcount with tcp_skb_pcount(skb) to later used that to update fack_count. To make it more explicit we track the new skb that gets incremented to pcount in @next_pcount, and we get to avoid the constant invocation of tcp_skb_pcount(skb) all together. Fixes: 832d11c5cd07 ("tcp: Try to restore large SKBs while SACK processing") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-15drm: don't block fb changes for async plane updatesHelen Koike1-0/+8
commit 89a4aac0ab0e6f5eea10d7bf4869dd15c3de2cd4 upstream. In the case of a normal sync update, the preparation of framebuffers (be it calling drm_atomic_helper_prepare_planes() or doing setups with drm_framebuffer_get()) are performed in the new_state and the respective cleanups are performed in the old_state. In the case of async updates, the preparation is also done in the new_state but the cleanups are done in the new_state (because updates are performed in place, i.e. in the current state). The current code blocks async udpates when the fb is changed, turning async updates into sync updates, slowing down cursor updates and introducing regressions in igt tests with errors of type: "CRITICAL: completed 97 cursor updated in a period of 30 flips, we expect to complete approximately 15360 updates, with the threshold set at 7680" Fb changes in async updates were prevented to avoid the following scenario: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1 - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 (wrong) Where we have a single call to prepare fb2 but double cleanup call to fb2. To solve the above problems, instead of blocking async fb changes, we place the old framebuffer in the new_state object, so when the code performs cleanups in the new_state it will cleanup the old_fb and we will have the following scenario instead: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, no cleanup - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb1 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 Where calls to prepare/cleanup are balanced. Cc: <stable@vger.kernel.org> # v4.14+ Fixes: 25dc194b34dd ("drm: Block fb changes for async plane updates") Suggested-by: Boris Brezillon <boris.brezillon@collabora.com> Signed-off-by: Helen Koike <helen.koike@collabora.com> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190603165610.24614-6-helen.koike@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-15Revert "Bluetooth: Align minimum encryption key size for LE and BR/EDR ↵Greg Kroah-Hartman1-3/+0
connections" This reverts commit 2fa7a155b25160696cd77cdd995536cf5e172e20 which is commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream. Lots of people have reported issues with this patch, and as there does not seem to be a fix going into Linus's kernel tree any time soon, revert the commit in the stable trees so as to get people's machines working properly again. Reported-by: Vasily Khoruzhick <anarsoul@gmail.com> Reported-by: Hans de Goede <hdegoede@redhat.com> Cc: Jeremy Cline <jeremy@jcline.org> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-15pwm: Fix deadlock warning when removing PWM devicePhong Hoang1-5/+0
[ Upstream commit 347ab9480313737c0f1aaa08e8f2e1a791235535 ] This patch fixes deadlock warning if removing PWM device when CONFIG_PROVE_LOCKING is enabled. This issue can be reproceduced by the following steps on the R-Car H3 Salvator-X board if the backlight is disabled: # cd /sys/class/pwm/pwmchip0 # echo 0 > export # ls device export npwm power pwm0 subsystem uevent unexport # cd device/driver # ls bind e6e31000.pwm uevent unbind # echo e6e31000.pwm > unbind [ 87.659974] ====================================================== [ 87.666149] WARNING: possible circular locking dependency detected [ 87.672327] 5.0.0 #7 Not tainted [ 87.675549] ------------------------------------------------------ [ 87.681723] bash/2986 is trying to acquire lock: [ 87.686337] 000000005ea0e178 (kn->count#58){++++}, at: kernfs_remove_by_name_ns+0x50/0xa0 [ 87.694528] [ 87.694528] but task is already holding lock: [ 87.700353] 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.707405] [ 87.707405] which lock already depends on the new lock. [ 87.707405] [ 87.715574] [ 87.715574] the existing dependency chain (in reverse order) is: [ 87.723048] [ 87.723048] -> #1 (pwm_lock){+.+.}: [ 87.728017] __mutex_lock+0x70/0x7e4 [ 87.732108] mutex_lock_nested+0x1c/0x24 [ 87.736547] pwm_request_from_chip.part.6+0x34/0x74 [ 87.741940] pwm_request_from_chip+0x20/0x40 [ 87.746725] export_store+0x6c/0x1f4 [ 87.750820] dev_attr_store+0x18/0x28 [ 87.754998] sysfs_kf_write+0x54/0x64 [ 87.759175] kernfs_fop_write+0xe4/0x1e8 [ 87.763615] __vfs_write+0x40/0x184 [ 87.767619] vfs_write+0xa8/0x19c [ 87.771448] ksys_write+0x58/0xbc [ 87.775278] __arm64_sys_write+0x18/0x20 [ 87.779721] el0_svc_common+0xd0/0x124 [ 87.783986] el0_svc_compat_handler+0x1c/0x24 [ 87.788858] el0_svc_compat+0x8/0x18 [ 87.792947] [ 87.792947] -> #0 (kn->count#58){++++}: [ 87.798260] lock_acquire+0xc4/0x22c [ 87.802353] __kernfs_remove+0x258/0x2c4 [ 87.806790] kernfs_remove_by_name_ns+0x50/0xa0 [ 87.811836] remove_files.isra.1+0x38/0x78 [ 87.816447] sysfs_remove_group+0x48/0x98 [ 87.820971] sysfs_remove_groups+0x34/0x4c [ 87.825583] device_remove_attrs+0x6c/0x7c [ 87.830197] device_del+0x11c/0x33c [ 87.834201] device_unregister+0x14/0x2c [ 87.838638] pwmchip_sysfs_unexport+0x40/0x4c [ 87.843509] pwmchip_remove+0xf4/0x13c [ 87.847773] rcar_pwm_remove+0x28/0x34 [ 87.852039] platform_drv_remove+0x24/0x64 [ 87.856651] device_release_driver_internal+0x18c/0x21c [ 87.862391] device_release_driver+0x14/0x1c [ 87.867175] unbind_store+0xe0/0x124 [ 87.871265] drv_attr_store+0x20/0x30 [ 87.875442] sysfs_kf_write+0x54/0x64 [ 87.879618] kernfs_fop_write+0xe4/0x1e8 [ 87.884055] __vfs_write+0x40/0x184 [ 87.888057] vfs_write+0xa8/0x19c [ 87.891887] ksys_write+0x58/0xbc [ 87.895716] __arm64_sys_write+0x18/0x20 [ 87.900154] el0_svc_common+0xd0/0x124 [ 87.904417] el0_svc_compat_handler+0x1c/0x24 [ 87.909289] el0_svc_compat+0x8/0x18 [ 87.913378] [ 87.913378] other info that might help us debug this: [ 87.913378] [ 87.921374] Possible unsafe locking scenario: [ 87.921374] [ 87.927286] CPU0 CPU1 [ 87.931808] ---- ---- [ 87.936331] lock(pwm_lock); [ 87.939293] lock(kn->count#58); [ 87.945120] lock(pwm_lock); [ 87.950599] lock(kn->count#58); [ 87.953908] [ 87.953908] *** DEADLOCK *** [ 87.953908] [ 87.959821] 4 locks held by bash/2986: [ 87.963563] #0: 00000000ace7bc30 (sb_writers#6){.+.+}, at: vfs_write+0x188/0x19c [ 87.971044] #1: 00000000287991b2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xb4/0x1e8 [ 87.978872] #2: 00000000f739d016 (&dev->mutex){....}, at: device_release_driver_internal+0x40/0x21c [ 87.988001] #3: 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.995481] [ 87.995481] stack backtrace: [ 87.999836] CPU: 0 PID: 2986 Comm: bash Not tainted 5.0.0 #7 [ 88.005489] Hardware name: Renesas Salvator-X board based on r8a7795 ES1.x (DT) [ 88.012791] Call trace: [ 88.015235] dump_backtrace+0x0/0x190 [ 88.018891] show_stack+0x14/0x1c [ 88.022204] dump_stack+0xb0/0xec [ 88.025514] print_circular_bug.isra.32+0x1d0/0x2e0 [ 88.030385] __lock_acquire+0x1318/0x1864 [ 88.034388] lock_acquire+0xc4/0x22c [ 88.037958] __kernfs_remove+0x258/0x2c4 [ 88.041874] kernfs_remove_by_name_ns+0x50/0xa0 [ 88.046398] remove_files.isra.1+0x38/0x78 [ 88.050487] sysfs_remove_group+0x48/0x98 [ 88.054490] sysfs_remove_groups+0x34/0x4c [ 88.058580] device_remove_attrs+0x6c/0x7c [ 88.062671] device_del+0x11c/0x33c [ 88.066154] device_unregister+0x14/0x2c [ 88.070070] pwmchip_sysfs_unexport+0x40/0x4c [ 88.074421] pwmchip_remove+0xf4/0x13c [ 88.078163] rcar_pwm_remove+0x28/0x34 [ 88.081906] platform_drv_remove+0x24/0x64 [ 88.085996] device_release_driver_internal+0x18c/0x21c [ 88.091215] device_release_driver+0x14/0x1c [ 88.095478] unbind_store+0xe0/0x124 [ 88.099048] drv_attr_store+0x20/0x30 [ 88.102704] sysfs_kf_write+0x54/0x64 [ 88.106359] kernfs_fop_write+0xe4/0x1e8 [ 88.110275] __vfs_write+0x40/0x184 [ 88.113757] vfs_write+0xa8/0x19c [ 88.117065] ksys_write+0x58/0xbc [ 88.120374] __arm64_sys_write+0x18/0x20 [ 88.124291] el0_svc_common+0xd0/0x124 [ 88.128034] el0_svc_compat_handler+0x1c/0x24 [ 88.132384] el0_svc_compat+0x8/0x18 The sysfs unexport in pwmchip_remove() is completely asymmetric to what we do in pwmchip_add_with_polarity() and commit 0733424c9ba9 ("pwm: Unexport children before chip removal") is a strong indication that this was wrong to begin with. We should just move pwmchip_sysfs_unexport() where it belongs, which is right after pwmchip_sysfs_unexport_children(). In that case, we do not need separate functions anymore either. We also really want to remove sysfs irrespective of whether or not the chip will be removed as a result of pwmchip_remove(). We can only assume that the driver will be gone after that, so we shouldn't leave any dangling sysfs files around. This warning disappears if we move pwmchip_sysfs_unexport() to the top of pwmchip_remove(), pwmchip_sysfs_unexport_children(). That way it is also outside of the pwm_lock section, which indeed doesn't seem to be needed. Moving the pwmchip_sysfs_export() call outside of that section also seems fine and it'd be perfectly symmetric with pwmchip_remove() again. So, this patch fixes them. Signed-off-by: Phong Hoang <phong.hoang.wz@renesas.com> [shimoda: revise the commit log and code] Fixes: 76abbdde2d95 ("pwm: Add sysfs interface") Fixes: 0733424c9ba9 ("pwm: Unexport children before chip removal") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Tested-by: Hoan Nguyen An <na-hoan@jinso.co.jp> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-11ipv4: Define __ipv4_neigh_lookup_noref when CONFIG_INET is disabledDavid Ahern1-0/+8
commit 9b3040a6aafd7898ece7fc7efcbca71e42aa8069 upstream. Define __ipv4_neigh_lookup_noref to return NULL when CONFIG_INET is disabled. Fixes: 4b2a2bfeb3f0 ("neighbor: Call __ipv4_neigh_lookup_noref in neigh_xmit") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11fuse: Add FOPEN_STREAM to use stream_open()Kirill Smelkov1-0/+2
commit bbd84f33652f852ce5992d65db4d020aba21f882 upstream. Starting from commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") files opened even via nonseekable_open gate read and write via lock and do not allow them to be run simultaneously. This can create read vs write deadlock if a filesystem is trying to implement a socket-like file which is intended to be simultaneously used for both read and write from filesystem client. See commit 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock") for details and e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes to /proc/xen/xenbus") for a similar deadlock example on /proc/xen/xenbus. To avoid such deadlock it was tempting to adjust fuse_finish_open to use stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE, and in particular GVFS which actually uses offset in its read and write handlers https://codesearch.debian.net/search?q=-%3Enonseekable+%3D https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481 so if we would do such a change it will break a real user. Add another flag (FOPEN_STREAM) for filesystem servers to indicate that the opened handler is having stream-like semantics; does not use file position and thus the kernel is free to issue simultaneous read and write request on opened file handle. This patch together with stream_open() should be added to stable kernels starting from v3.14+. This will allow to patch OSSPD and other FUSE filesystems that provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE in open handler and this way avoid the deadlock on all kernel versions. This should work because fuse_finish_open ignores unknown open flags returned from a filesystem and so passing FOPEN_STREAM to a kernel that is not aware of this flag cannot hurt. In turn the kernel that is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE is sufficient to implement streams without read vs write deadlock. Cc: stable@vger.kernel.org # v3.14+ Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11fs: stream_open - opener for stream-like files so that read and write can ↵Kirill Smelkov1-0/+4
run simultaneously without deadlock commit 10dce8af34226d90fa56746a934f8da5dcdba3df upstream. Commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") added locking for file.f_pos access and in particular made concurrent read and write not possible - now both those functions take f_pos lock for the whole run, and so if e.g. a read is blocked waiting for data, write will deadlock waiting for that read to complete. This caused regression for stream-like files where previously read and write could run simultaneously, but after that patch could not do so anymore. See e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes to /proc/xen/xenbus") which fixes such regression for particular case of /proc/xen/xenbus. The patch that added f_pos lock in 2014 did so to guarantee POSIX thread safety for read/write/lseek and added the locking to file descriptors of all regular files. In 2014 that thread-safety problem was not new as it was already discussed earlier in 2006. However even though 2006'th version of Linus's patch was adding f_pos locking "only for files that are marked seekable with FMODE_LSEEK (thus avoiding the stream-like objects like pipes and sockets)", the 2014 version - the one that actually made it into the tree as 9c225f2655e3 - is doing so irregardless of whether a file is seekable or not. See https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/ https://lwn.net/Articles/180387 https://lwn.net/Articles/180396 for historic context. The reason that it did so is, probably, that there are many files that are marked non-seekable, but e.g. their read implementation actually depends on knowing current position to correctly handle the read. Some examples: kernel/power/user.c snapshot_read fs/debugfs/file.c u32_array_read fs/fuse/control.c fuse_conn_waiting_read + ... drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read arch/s390/hypfs/inode.c hypfs_read_iter ... Despite that, many nonseekable_open users implement read and write with pure stream semantics - they don't depend on passed ppos at all. And for those cases where read could wait for something inside, it creates a situation similar to xenbus - the write could be never made to go until read is done, and read is waiting for some, potentially external, event, for potentially unbounded time -> deadlock. Besides xenbus, there are 14 such places in the kernel that I've found with semantic patch (see below): drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write() drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write() drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write() drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write() net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write() drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write() drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write() drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write() net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write() drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write() drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write() drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write() drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write() drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write() In addition to the cases above another regression caused by f_pos locking is that now FUSE filesystems that implement open with FOPEN_NONSEEKABLE flag, can no longer implement bidirectional stream-like files - for the same reason as above e.g. read can deadlock write locking on file.f_pos in the kernel. FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f715 ("fuse: implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and write routines not depending on current position at all, and with both read and write being potentially blocking operations: See https://github.com/libfuse/osspd https://lwn.net/Articles/308445 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510 Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as "somewhat pipe-like files ..." with read handler not using offset. However that test implements only read without write and cannot exercise the deadlock scenario: https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216 I've actually hit the read vs write deadlock for real while implementing my FUSE filesystem where there is /head/watch file, for which open creates separate bidirectional socket-like stream in between filesystem and its user with both read and write being later performed simultaneously. And there it is semantically not easy to split the stream into two separate read-only and write-only channels: https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169 Let's fix this regression. The plan is: 1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS - doing so would break many in-kernel nonseekable_open users which actually use ppos in read/write handlers. 2. Add stream_open() to kernel to open stream-like non-seekable file descriptors. Read and write on such file descriptors would never use nor change ppos. And with that property on stream-like files read and write will be running without taking f_pos lock - i.e. read and write could be running simultaneously. 3. With semantic patch search and convert to stream_open all in-kernel nonseekable_open users for which read and write actually do not depend on ppos and where there is no other methods in file_operations which assume @offset access. 4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via steam_open if that bit is present in filesystem open reply. It was tempting to change fs/fuse/ open handler to use stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE, and in particular GVFS which actually uses offset in its read and write handlers https://codesearch.debian.net/search?q=-%3Enonseekable+%3D https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481 so if we would do such a change it will break a real user. 5. Add stream_open and FOPEN_STREAM handling to stable kernels starting from v3.14+ (the kernel where 9c225f2655 first appeared). This will allow to patch OSSPD and other FUSE filesystems that provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE in their open handler and this way avoid the deadlock on all kernel versions. This should work because fs/fuse/ ignores unknown open flags returned from a filesystem and so passing FOPEN_STREAM to a kernel that is not aware of this flag cannot hurt. In turn the kernel that is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE is sufficient to implement streams without read vs write deadlock. This patch adds stream_open, converts /proc/xen/xenbus to it and adds semantic patch to automatically locate in-kernel places that are either required to be converted due to read vs write deadlock, or that are just safe to be converted because read and write do not use ppos and there are no other funky methods in file_operations. Regarding semantic patch I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. The script also does not convert files that should be valid to convert, but that currently have .llseek = noop_llseek or generic_file_llseek for unknown reason despite file being opened with nonseekable_open (e.g. drivers/input/mousedev.c) Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yongzhi Pan <panyongzhi@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Nikolaus Rath <Nikolaus@rath.org> Cc: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11drm/i915: Fix I915_EXEC_RING_MASKChris Wilson1-1/+1
commit d90c06d57027203f73021bb7ddb30b800d65c636 upstream. This was supposed to be a mask of all known rings, but it is being used by execbuffer to filter out invalid rings, and so is instead mapping high unused values onto valid rings. Instead of a mask of all known rings, we need it to be the mask of all possible rings. Fixes: 549f7365820a ("drm/i915: Enable SandyBridge blitter ring") Fixes: de1add360522 ("drm/i915: Decouple execbuf uAPI from internal implementation") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: <stable@vger.kernel.org> # v4.6+ Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190301140404.26690-21-chris@chris-wilson.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11x86/power: Fix 'nosmt' vs hibernation triple fault during resumeJiri Kosina1-0/+4
commit ec527c318036a65a083ef68d8ba95789d2212246 upstream. As explained in 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") we always, no matter what, have to bring up x86 HT siblings during boot at least once in order to avoid first MCE bringing the system to its knees. That means that whenever 'nosmt' is supplied on the kernel command-line, all the HT siblings are as a result sitting in mwait or cpudile after going through the online-offline cycle at least once. This causes a serious issue though when a kernel, which saw 'nosmt' on its commandline, is going to perform resume from hibernation: if the resume from the hibernated image is successful, cr3 is flipped in order to point to the address space of the kernel that is being resumed, which in turn means that all the HT siblings are all of a sudden mwaiting on address which is no longer valid. That results in triple fault shortly after cr3 is switched, and machine reboots. Fix this by always waking up all the SMT siblings before initiating the 'restore from hibernation' process; this guarantees that all the HT siblings will be properly carried over to the resumed kernel waiting in resume_play_dead(), and acted upon accordingly afterwards, based on the target kernel configuration. Symmetricaly, the resumed kernel has to push the SMT siblings to mwait again in case it has SMT disabled; this means it has to online all the siblings when resuming (so that they come out of hlt) and offline them again to let them reach mwait. Cc: 4.19+ <stable@vger.kernel.org> # v4.19+ Debugged-by: Thomas Gleixner <tglx@linutronix.de> Fixes: 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Pavel Machek <pavel@ucw.cz> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11pstore: Convert buf_lock to semaphoreKees Cook1-4/+3
commit ea84b580b95521644429cc6748b6c2bf27c8b0f3 upstream. Instead of running with interrupts disabled, use a semaphore. This should make it easier for backends that may need to sleep (e.g. EFI) when performing a write: |BUG: sleeping function called from invalid context at kernel/sched/completion.c:99 |in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum |Preemption disabled at: |[<ffffffff99d60512>] pstore_dump+0x72/0x330 |CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45 |Call Trace: | dump_stack+0x4f/0x6a | ___might_sleep.cold.91+0xd3/0xe4 | __might_sleep+0x50/0x90 | wait_for_completion+0x32/0x130 | virt_efi_query_variable_info+0x14e/0x160 | efi_query_variable_store+0x51/0x1a0 | efivar_entry_set_safe+0xa3/0x1b0 | efi_pstore_write+0x109/0x140 | pstore_dump+0x11c/0x330 | kmsg_dump+0xa4/0xd0 | oops_exit+0x22/0x30 ... Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Fixes: 21b3ddd39fee ("efi: Don't use spinlocks for efi vars") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11rcu: locking and unlocking need to always be at least barriersLinus Torvalds1-4/+2
commit 66be4e66a7f422128748e3c3ef6ee72b20a6197b upstream. Herbert Xu pointed out that commit bb73c52bad36 ("rcu: Don't disable preemption for Tiny and Tree RCU readers") was incorrect in making the preempt_disable/enable() be conditional on CONFIG_PREEMPT_COUNT. If CONFIG_PREEMPT_COUNT isn't enabled, the preemption enable/disable is a no-op, but still is a compiler barrier. And RCU locking still _needs_ that compiler barrier. It is simply fundamentally not true that RCU locking would be a complete no-op: we still need to guarantee (for example) that things that can trap and cause preemption cannot migrate into the RCU locked region. The way we do that is by making it a barrier. See for example commit 386afc91144b ("spinlocks and preemption points need to be at least compiler barriers") from back in 2013 that had similar issues with spinlocks that become no-ops on UP: they must still constrain the compiler from moving other operations into the critical region. Now, it is true that a lot of RCU operations already use READ_ONCE() and WRITE_ONCE() (which in practice likely would never be re-ordered wrt anything remotely interesting), but it is also true that that is not globally the case, and that it's not even necessarily always possible (ie bitfields etc). Reported-by: Herbert Xu <herbert@gondor.apana.org.au> Fixes: bb73c52bad36 ("rcu: Don't disable preemption for Tiny and Tree RCU readers") Cc: stable@kernel.org Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11ipv6: fix the check before getting the cookie in rt6_get_cookieXin Long1-2/+1
[ Upstream commit b7999b07726c16974ba9ca3bb9fe98ecbec5f81c ] In Jianlin's testing, netperf was broken with 'Connection reset by peer', as the cookie check failed in rt6_check() and ip6_dst_check() always returned NULL. It's caused by Commit 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes"), where the cookie can be got only when 'c1'(see below) for setting dst_cookie whereas rt6_check() is called when !'c1' for checking dst_cookie, as we can see in ip6_dst_check(). Since in ip6_dst_check() both rt6_dst_from_check() (c1) and rt6_check() (!c1) will check the 'from' cookie, this patch is to remove the c1 check in rt6_get_cookie(), so that the dst_cookie can always be set properly. c1: (rt->rt6i_flags & RTF_PCPU || unlikely(!list_empty(&rt->rt6i_uncached))) Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09include/linux/module.h: copy __init/__exit attrs to init/cleanup_moduleMiguel Ojeda1-2/+2
commit a6e60d84989fa0e91db7f236eda40453b0e44afa upstream. The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target. In particular, it triggers for all the init/cleanup_module aliases in the kernel (defined by the module_init/exit macros), ending up being very noisy. These aliases point to the __init/__exit functions of a module, which are defined as __cold (among other attributes). However, the aliases themselves do not have the __cold attribute. Since the compiler behaves differently when compiling a __cold function as well as when compiling paths leading to calls to __cold functions, the warning is trying to point out the possibly-forgotten attribute in the alias. In order to keep the warning enabled, we decided to silence this case. Ideally, we would mark the aliases directly as __init/__exit. However, there are currently around 132 modules in the kernel which are missing __init/__exit in their init/cleanup functions (either because they are missing, or for other reasons, e.g. the functions being called from somewhere else); and a section mismatch is a hard error. A conservative alternative was to mark the aliases as __cold only. However, since we would like to eventually enforce __init/__exit to be always marked, we chose to use the new __copy function attribute (introduced by GCC 9 as well to deal with this). With it, we copy the attributes used by the target functions into the aliases. This way, functions that were not marked as __init/__exit won't have their aliases marked either, and therefore there won't be a section mismatch. Note that the warning would go away marking either the extern declaration, the definition, or both. However, we only mark the definition of the alias, since we do not want callers (which only see the declaration) to be compiled as if the function was __cold (and therefore the paths leading to those calls would be assumed to be unlikely). Link: https://lore.kernel.org/lkml/20190123173707.GA16603@gmail.com/ Link: https://lore.kernel.org/lkml/20190206175627.GA20399@gmail.com/ Suggested-by: Martin Sebor <msebor@gcc.gnu.org> Acked-by: Jessica Yu <jeyu@kernel.org> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09Compiler Attributes: add support for __copy (gcc >= 9)Miguel Ojeda2-0/+8
commit c0d9782f5b6d7157635ae2fd782a4b27d55a6013 upstream. From the GCC manual: copy copy(function) The copy attribute applies the set of attributes with which function has been declared to the declaration of the function to which the attribute is applied. The attribute is designed for libraries that define aliases or function resolvers that are expected to specify the same set of attributes as their targets. The copy attribute can be used with functions, variables, or types. However, the kind of symbol to which the attribute is applied (either function or variable) must match the kind of symbol to which the argument refers. The copy attribute copies only syntactic and semantic attributes but not attributes that affect a symbol’s linkage or visibility such as alias, visibility, or weak. The deprecated attribute is also not copied. https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target, e.g.: void __cold f(void) {} void __alias("f") g(void); diagnoses: warning: 'g' specifies less restrictive attribute than its target 'f': 'cold' [-Wmissing-attributes] Using __copy(f) we can copy the __cold attribute from f to g: void __cold f(void) {} void __copy(f) __alias("f") g(void); This attribute is most useful to deal with situations where an alias is declared but we don't know the exact attributes the target has. For instance, in the kernel, the widely used module_init/exit macros define the init/cleanup_module aliases, but those cannot be marked always as __init/__exit since some modules do not have their functions marked as such. Suggested-by: Martin Sebor <msebor@gcc.gnu.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09memcg: make it work on sparse non-0-node systemsJiri Slaby1-0/+1
commit 3e8589963773a5c23e2f1fe4bcad0e9a90b7f471 upstream. We have a single node system with node 0 disabled: Scanning NUMA topology in Northbridge 24 Number of physical nodes 2 Skipping disabled node 0 Node 1 MemBase 0000000000000000 Limit 00000000fbff0000 NODE_DATA(1) allocated [mem 0xfbfda000-0xfbfeffff] This causes crashes in memcg when system boots: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 #PF error: [normal kernel read fault] ... RIP: 0010:list_lru_add+0x94/0x170 ... Call Trace: d_lru_add+0x44/0x50 dput.part.34+0xfc/0x110 __fput+0x108/0x230 task_work_run+0x9f/0xc0 exit_to_usermode_loop+0xf5/0x100 It is reproducible as far as 4.12. I did not try older kernels. You have to have a new enough systemd, e.g. 241 (the reason is unknown -- was not investigated). Cannot be reproduced with systemd 234. The system crashes because the size of lru array is never updated in memcg_update_all_list_lrus and the reads are past the zero-sized array, causing dereferences of random memory. The root cause are list_lru_memcg_aware checks in the list_lru code. The test in list_lru_memcg_aware is broken: it assumes node 0 is always present, but it is not true on some systems as can be seen above. So fix this by avoiding checks on node 0. Remember the memcg-awareness by a bool flag in struct list_lru. Link: http://lkml.kernel.org/r/20190522091940.3615-1-jslaby@suse.cz Fixes: 60d3fd32a7a9 ("list_lru: introduce per-memcg lists") Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vladimir Davydov <vdavydov.dev@gmail.com> Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09include/linux/bitops.h: sanitize rotate primitivesRasmus Villemoes1-8/+8
commit ef4d6f6b275c498f8e5626c99dbeefdc5027f843 upstream. The ror32 implementation (word >> shift) | (word << (32 - shift) has undefined behaviour if shift is outside the [1, 31] range. Similarly for the 64 bit variants. Most callers pass a compile-time constant (naturally in that range), but there's an UBSAN report that these may actually be called with a shift count of 0. Instead of special-casing that, we can make them DTRT for all values of shift while also avoiding UB. For some reason, this was already partly done for rol32 (which was well-defined for [0, 31]). gcc 8 recognizes these patterns as rotates, so for example __u32 rol32(__u32 word, unsigned int shift) { return (word << (shift & 31)) | (word >> ((-shift) & 31)); } compiles to 0000000000000020 <rol32>: 20: 89 f8 mov %edi,%eax 22: 89 f1 mov %esi,%ecx 24: d3 c0 rol %cl,%eax 26: c3 retq Older compilers unfortunately do not do as well, but this only affects the small minority of users that don't pass constants. Due to integer promotions, ro[lr]8 were already well-defined for shifts in [0, 8], and ro[lr]16 were mostly well-defined for shifts in [0, 16] (only mostly - u16 gets promoted to _signed_ int, so if bit 15 is set, word << 16 is undefined). For consistency, update those as well. Link: http://lkml.kernel.org/r/20190410211906.2190-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Ido Schimmel <idosch@mellanox.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Vadim Pasternak <vadimp@mellanox.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09tipc: Avoid copying bytes beyond the supplied dataChris Packham1-3/+7
TLV_SET is called with a data pointer and a len parameter that tells us how many bytes are pointed to by data. When invoking memcpy() we need to careful to only copy len bytes. Previously we would copy TLV_LENGTH(len) bytes which would copy an extra 4 bytes past the end of the data pointer which newer GCC versions complain about. In file included from test.c:17: In function 'TLV_SET', inlined from 'test' at test.c:186:5: /usr/include/linux/tipc_config.h:317:3: warning: 'memcpy' forming offset [33, 36] is out of the bounds [0, 32] of object 'bearer_name' with type 'char[32]' [-Warray-bounds] memcpy(TLV_DATA(tlv_ptr), data, tlv_len); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ test.c: In function 'test': test.c::161:10: note: 'bearer_name' declared here char bearer_name[TIPC_MAX_BEARER_NAME]; ^~~~~~~~~~~ We still want to ensure any padding bytes at the end are initialised, do this with a explicit memset() rather than copy bytes past the end of data. Apply the same logic to TCM_SET. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09inet: switch IP ID generator to siphashEric Dumazet2-0/+7
[ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ] According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31HID: core: move Usage Page concatenation to Main itemNicolas Saenz Julienne1-0/+1
[ Upstream commit 58e75155009cc800005629955d3482f36a1e0eec ] As seen on some USB wireless keyboards manufactured by Primax, the HID parser was using some assumptions that are not always true. In this case it's s the fact that, inside the scope of a main item, an Usage Page will always precede an Usage. The spec is not pretty clear as 6.2.2.7 states "Any usage that follows is interpreted as a Usage ID and concatenated with the Usage Page". While 6.2.2.8 states "When the parser encounters a main item it concatenates the last declared Usage Page with a Usage to form a complete usage value." Being somewhat contradictory it was decided to match Window's implementation, which follows 6.2.2.8. In summary, the patch moves the Usage Page concatenation from the local item parsing function to the main item parsing function. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Reviewed-by: Terry Junge <terry.junge@poly.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31iio: ad_sigma_delta: Properly handle SPI bus locking vs CS assertionLars-Peter Clausen1-0/+1
[ Upstream commit df1d80aee963480c5c2938c64ec0ac3e4a0df2e0 ] For devices from the SigmaDelta family we need to keep CS low when doing a conversion, since the device will use the MISO line as a interrupt to indicate that the conversion is complete. This is why the driver locks the SPI bus and when the SPI bus is locked keeps as long as a conversion is going on. The current implementation gets one small detail wrong though. CS is only de-asserted after the SPI bus is unlocked. This means it is possible for a different SPI device on the same bus to send a message which would be wrongfully be addressed to the SigmaDelta device as well. Make sure that the last SPI transfer that is done while holding the SPI bus lock de-asserts the CS signal. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Alexandru Ardelean <Alexandru.Ardelean@analog.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31cgroup: protect cgroup->nr_(dying_)descendants by css_set_lockRoman Gushchin1-0/+5
[ Upstream commit 4dcabece4c3a9f9522127be12cc12cc120399b2f ] The number of descendant cgroups and the number of dying descendant cgroups are currently synchronized using the cgroup_mutex. The number of descendant cgroups will be required by the cgroup v2 freezer, which will use it to determine if a cgroup is frozen (depending on total number of descendants and number of frozen descendants). It's not always acceptable to grab the cgroup_mutex, especially from quite hot paths (e.g. exit()). To avoid this, let's additionally synchronize these counters using the css_set_lock. So, it's safe to read these counters with either cgroup_mutex or css_set_lock locked, and for changing both locks should be acquired. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: kernel-team@fb.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31smpboot: Place the __percpu annotation correctlySebastian Andrzej Siewior1-1/+1
[ Upstream commit d4645d30b50d1691c26ff0f8fa4e718b08f8d3bb ] The test robot reported a wrong assignment of a per-CPU variable which it detected by using sparse and sent a report. The assignment itself is correct. The annotation for sparse was wrong and hence the report. The first pointer is a "normal" pointer and points to the per-CPU memory area. That means that the __percpu annotation has to be moved. Move the __percpu annotation to pointer which points to the per-CPU area. This change affects only the sparse tool (and is ignored by the compiler). Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: f97f8f06a49fe ("smpboot: Provide infrastructure for percpu hotplug threads") Link: http://lkml.kernel.org/r/20190424085253.12178-1-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31hugetlb: use same fault hash key for shared and private mappingsMike Kravetz1-3/+1
commit 1b426bac66e6cc83c9f2d92b96e4e72acf43419a upstream. hugetlb uses a fault mutex hash table to prevent page faults of the same pages concurrently. The key for shared and private mappings is different. Shared keys off address_space and file index. Private keys off mm and virtual address. Consider a private mappings of a populated hugetlbfs file. A fault will map the page from the file and if needed do a COW to map a writable page. Hugetlbfs hole punch uses the fault mutex to prevent mappings of file pages. It uses the address_space file index key. However, private mappings will use a different key and could race with this code to map the file page. This causes problems (BUG) for the page cache remove code as it expects the page to be unmapped. A sample stack is: page dumped because: VM_BUG_ON_PAGE(page_mapped(page)) kernel BUG at mm/filemap.c:169! ... RIP: 0010:unaccount_page_cache_page+0x1b8/0x200 ... Call Trace: __delete_from_page_cache+0x39/0x220 delete_from_page_cache+0x45/0x70 remove_inode_hugepages+0x13c/0x380 ? __add_to_page_cache_locked+0x162/0x380 hugetlbfs_fallocate+0x403/0x540 ? _cond_resched+0x15/0x30 ? __inode_security_revalidate+0x5d/0x70 ? selinux_file_permission+0x100/0x130 vfs_fallocate+0x13f/0x270 ksys_fallocate+0x3c/0x80 __x64_sys_fallocate+0x1a/0x20 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 There seems to be another potential COW issue/race with this approach of different private and shared keys as noted in commit 8382d914ebf7 ("mm, hugetlb: improve page-fault scalability"). Since every hugetlb mapping (even anon and private) is actually a file mapping, just use the address_space index key for all mappings. This results in potentially more hash collisions. However, this should not be the common case. Link: http://lkml.kernel.org/r/20190328234704.27083-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20190412165235.t4sscoujczfhuiyt@linux-r8p5 Fixes: b5cec28d36f5 ("hugetlbfs: truncate_hugepages() takes a range of pages") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31bio: fix improper use of smp_mb__before_atomic()Andrea Parri1-1/+1
commit f381c6a4bd0ae0fde2d6340f1b9bb0f58d915de6 upstream. This barrier only applies to the read-modify-write operations; in particular, it does not apply to the atomic_set() primitive. Replace the barrier with an smp_mb(). Fixes: dac56212e8127 ("bio: skip atomic inc/dec of ->bi_cnt for most use cases") Cc: stable@vger.kernel.org Reported-by: "Paul E. McKenney" <paulmck@linux.ibm.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Ming Lei <ming.lei@redhat.com> Cc: linux-block@vger.kernel.org Cc: "Paul E. McKenney" <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25bpf: add map_lookup_elem_sys_only for lookups from syscall sideDaniel Borkmann1-0/+1
commit c6110222c6f49ea68169f353565eb865488a8619 upstream. Add a callback map_lookup_elem_sys_only() that map implementations could use over map_lookup_elem() from system call side in case the map implementation needs to handle the latter differently than from the BPF data path. If map_lookup_elem_sys_only() is set, this will be preferred pick for map lookups out of user space. This hook is used in a follow-up fix for LRU map, but once development window opens, we can convert other map types from map_lookup_elem() (here, the one called upon BPF_MAP_LOOKUP_ELEM cmd is meant) over to use the callback to simplify and clean up the latter. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratumStefan Mätje1-0/+2
commit 4ec73791a64bab25cabf16a6067ee478692e506d upstream. Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode (conventional PCI on primary side, PCIe on downstream side), the Retrain Link bit needs to be cleared manually to allow the link training to complete successfully. If it is not cleared manually, the link training is continuously restarted and no devices below the PCI-to-PCIe bridge can be accessed. That means drivers for devices below the bridge will be loaded but won't work and may even crash because the driver is only reading 0xffff. See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for details. Devices known as affected so far are: PI7C9X110, PI7C9X111SL, PI7C9X130. Add a new flag, clear_retrain_link, in struct pci_dev. Quirks for affected devices set this bit. Note that pcie_retrain_link() lives in aspm.c because that's currently the only place we use it, but this erratum is not specific to ASPM, and we may retrain links for other reasons in the future. Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu> [bhelgaas: apply regardless of CONFIG_PCIEASPM] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> CC: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25of: fix clang -Wunsequenced for be32_to_cpu()Phong Tran1-2/+2
commit 440868661f36071886ed360d91de83bd67c73b4f upstream. Now, make the loop explicit to avoid clang warning. ./include/linux/of.h:238:37: warning: multiple unsequenced modifications to 'cell' [-Wunsequenced] r = (r << 32) | be32_to_cpu(*(cell++)); ^~ ./include/linux/byteorder/generic.h:95:21: note: expanded from macro 'be32_to_cpu' ^ ./include/uapi/linux/byteorder/little_endian.h:40:59: note: expanded from macro '__be32_to_cpu' ^ ./include/uapi/linux/swab.h:118:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ ./include/uapi/linux/swab.h:18:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ ^ Signed-off-by: Phong Tran <tranmanphong@gmail.com> Reported-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://github.com/ClangBuiltLinux/linux/issues/460 Suggested-by: David Laight <David.Laight@ACULAB.COM> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Cc: stable@vger.kernel.org [robh: fix up whitespace] Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25net: test nouarg before dereferencing zerocopy pointersWillem de Bruijn1-3/+6
[ Upstream commit 185ce5c38ea76f29b6bd9c7c8c7a5e5408834920 ] Zerocopy skbs without completion notification were added for packet sockets with PACKET_TX_RING user buffers. Those signal completion through the TP_STATUS_USER bit in the ring. Zerocopy annotation was added only to avoid premature notification after clone or orphan, by triggering a copy on these paths for these packets. The mechanism had to define a special "no-uarg" mode because packet sockets already use skb_uarg(skb) == skb_shinfo(skb)->destructor_arg for a different pointer. Before deferencing skb_uarg(skb), verify that it is a real pointer. Fixes: 5cd8d46ea1562 ("packet: copy user buffers before orphan or clone") Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21mfd: max77620: Fix swapped FPS_PERIOD_MAX_US valuesDmitry Osipenko1-2/+2
commit ea611d1cc180fbb56982c83cd5142a2b34881f5c upstream. The FPS_PERIOD_MAX_US definitions are swapped for MAX20024 and MAX77620, fix it. Cc: stable <stable@vger.kernel.org> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21mfd: da9063: Fix OTP control register names to match datasheets for DA9063/63LSteve Twiss1-3/+3
commit 6b4814a9451add06d457e198be418bf6a3e6a990 upstream. Mismatch between what is found in the Datasheets for DA9063 and DA9063L provided by Dialog Semiconductor, and the register names provided in the MFD registers file. The changes are for the OTP (one-time-programming) control registers. The two naming errors are OPT instead of OTP, and COUNT instead of CONT (i.e. control). Cc: Stable <stable@vger.kernel.org> Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21net: core: another layer of lists, around PF_MEMALLOC skb handlingSasha Levin1-0/+30
[ Upstream commit 78ed8cc25986ac5c21762eeddc1e86e94d422e36 ] First example of a layer splitting the list (rather than merely taking individual packets off it). Involves new list.h function, list_cut_before(), like list_cut_position() but cuts on the other side of the given entry. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> [sl: cut out non list.h bits, we only want list_cut_before] Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-16nfc: nci: Potential off by one in ->pipes[] arrayDan Carpenter1-1/+1
[ Upstream commit 6491d698396fd5da4941980a35ca7c162a672016 ] This is similar to commit e285d5bfb7e9 ("NFC: Fix the number of pipes") where we changed NFC_HCI_MAX_PIPES from 127 to 128. As the comment next to the define explains, the pipe identifier is 7 bits long. The highest possible pipe is 127, but the number of possible pipes is 128. As the code is now, then there is potential for an out of bounds array access: net/nfc/nci/hci.c:297 nci_hci_cmd_received() warn: array off by one? 'ndev->hci_dev->pipes[pipe]' '0-127 == 127' Fixes: 11f54f228643 ("NFC: nci: Add HCI over NCI protocol support") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
2019-05-16RDMA/vmw_pvrdma: Return the correct opcode when creating WRAdit Ranadive1-0/+1
[ Upstream commit 6325e01b6cdf4636b721cf7259c1616e3cf28ce2 ] Since the IB_WR_REG_MR opcode value changed, let's set the PVRDMA device opcodes explicitly. Reported-by: Ruishuang Wang <ruishuangw@vmware.com> Fixes: 9a59739bd01f ("IB/rxe: Revise the ib_wr_opcode enum") Cc: stable@vger.kernel.org Reviewed-by: Bryan Tan <bryantan@vmware.com> Reviewed-by: Ruishuang Wang <ruishuangw@vmware.com> Reviewed-by: Vishnu Dasa <vdasa@vmware.com> Signed-off-by: Adit Ranadive <aditr@vmware.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>