summaryrefslogtreecommitdiff
AgeCommit message (Collapse)AuthorFilesLines
2020-05-20virtio-blk: handle block_device_operations callbacks after hot unplugStefan Hajnoczi1-8/+78
[ Upstream commit 90b5feb8c4bebc76c27fcaf3e1a0e5ca2d319e9e ] A userspace process holding a file descriptor to a virtio_blk device can still invoke block_device_operations after hot unplug. This leads to a use-after-free accessing vblk->vdev in virtblk_getgeo() when ioctl(HDIO_GETGEO) is invoked: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90 [virtio] PGD 800000003a92f067 PUD 3a930067 PMD 0 Oops: 0000 [#1] SMP CPU: 0 PID: 1310 Comm: hdio-getgeo Tainted: G OE ------------ 3.10.0-1062.el7.x86_64 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 task: ffff9be5fbfb8000 ti: ffff9be5fa890000 task.ti: ffff9be5fa890000 RIP: 0010:[<ffffffffc00e5450>] [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90 [virtio] RSP: 0018:ffff9be5fa893dc8 EFLAGS: 00010246 RAX: ffff9be5fc3f3400 RBX: ffff9be5fa893e30 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff9be5fbc10b40 RBP: ffff9be5fa893dc8 R08: 0000000000000301 R09: 0000000000000301 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9be5fdc24680 R13: ffff9be5fbc10b40 R14: ffff9be5fbc10480 R15: 0000000000000000 FS: 00007f1bfb968740(0000) GS:ffff9be5ffc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000090 CR3: 000000003a894000 CR4: 0000000000360ff0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: [<ffffffffc016ac37>] virtblk_getgeo+0x47/0x110 [virtio_blk] [<ffffffff8d3f200d>] ? handle_mm_fault+0x39d/0x9b0 [<ffffffff8d561265>] blkdev_ioctl+0x1f5/0xa20 [<ffffffff8d488771>] block_ioctl+0x41/0x50 [<ffffffff8d45d9e0>] do_vfs_ioctl+0x3a0/0x5a0 [<ffffffff8d45dc81>] SyS_ioctl+0xa1/0xc0 A related problem is that virtblk_remove() leaks the vd_index_ida index when something still holds a reference to vblk->disk during hot unplug. This causes virtio-blk device names to be lost (vda, vdb, etc). Fix these issues by protecting vblk->vdev with a mutex and reference counting vblk so the vd_index_ida index can be removed in all cases. Fixes: 48e4043d4529 ("virtio: add virtio disk geometry feature") Reported-by: Lance Digby <ldigby@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200430140442.171016-1-stefanha@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20drop_monitor: work around gcc-10 stringop-overflow warningArnd Bergmann1-4/+7
[ Upstream commit dc30b4059f6e2abf3712ab537c8718562b21c45d ] The current gcc-10 snapshot produces a false-positive warning: net/core/drop_monitor.c: In function 'trace_drop_common.constprop': cc1: error: writing 8 bytes into a region of size 0 [-Werror=stringop-overflow=] In file included from net/core/drop_monitor.c:23: include/uapi/linux/net_dropmon.h:36:8: note: at offset 0 to object 'entries' with size 4 declared here 36 | __u32 entries; | ^~~~~~~ I reported this in the gcc bugzilla, but in case it does not get fixed in the release, work around it by using a temporary variable. Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol") Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94881 Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20ftrace/selftests: workaround cgroup RT scheduling issuesAlan Maguire1-0/+22
[ Upstream commit 57c4cfd4a2eef8f94052bd7c0fce0981f74fb213 ] wakeup_rt.tc and wakeup.tc tests in tracers/ subdirectory fail due to the chrt command returning: chrt: failed to set pid 0's policy: Operation not permitted. To work around this, temporarily disable grout RT scheduling during ftracetest execution. Restore original value on test run completion. With these changes in place, both tests consistently pass. Fixes: c575dea2c1a5 ("selftests/ftrace: Add wakeup_rt tracer testcase") Fixes: c1edd060b413 ("selftests/ftrace: Add wakeup tracer testcase") Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20net: moxa: Fix a potential double 'free_irq()'Christophe JAILLET1-1/+1
[ Upstream commit ee8d2267f0e39a1bfd95532da3a6405004114b27 ] Should an irq requested with 'devm_request_irq' be released explicitly, it should be done by 'devm_free_irq()', not 'free_irq()'. Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20net/sonic: Fix a resource leak in an error handling path in 'jazz_sonic_probe()'Christophe JAILLET1-2/+4
[ Upstream commit 10e3cc180e64385edc9890c6855acf5ed9ca1339 ] A call to 'dma_alloc_coherent()' is hidden in 'sonic_alloc_descriptors()', called from 'sonic_probe1()'. This is correctly freed in the remove function, but not in the error handling path of the probe function. Fix it and add the missing 'dma_free_coherent()' call. While at it, rename a label in order to be slightly more informative. Fixes: efcce839360f ("[PATCH] macsonic/jazzsonic network drivers update") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20SUNRPC: Fix GSS privacy computation of auth->au_ralignChuck Lever3-9/+19
[ Upstream commit a7e429a6fa6d612d1dacde96c885dc1bb4a9f400 ] When the au_ralign field was added to gss_unwrap_resp_priv, the wrong calculation was used. Setting au_rslack == au_ralign is probably correct for kerberos_v1 privacy, but kerberos_v2 privacy adds additional GSS data after the clear text RPC message. au_ralign needs to be smaller than au_rslack in that fairly common case. When xdr_buf_trim() is restored to gss_unwrap_kerberos_v2(), it does exactly what I feared it would: it trims off part of the clear text RPC message. However, that's because rpc_prepare_reply_pages() does not set up the rq_rcv_buf's tail correctly because au_ralign is too large. Fixing the au_ralign computation also corrects the alignment of rq_rcv_buf->pages so that the client does not have to shift reply data payloads after they are received. Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20SUNRPC: Add "@len" parameter to gss_unwrap()Chuck Lever7-27/+30
[ Upstream commit 31c9590ae468478fe47dc0f5f0d3562b2f69450e ] Refactor: This is a pre-requisite to fixing the client-side ralign computation in gss_unwrap_resp_priv(). The length value is passed in explicitly rather that as the value of buf->len. This will subsequently allow gss_unwrap_kerberos_v1() to compute a slack and align value, instead of computing it in gss_unwrap_resp_priv(). Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20gpio: pca953x: Fix pca953x_gpio_set_configAdam Ford1-1/+1
[ Upstream commit dc87f6dd058a648cd2a35e4aa04592dccdc9f0c2 ] pca953x_gpio_set_config is setup to support pull-up/down bias. Currently the driver uses a variable called 'config' to determine which options to use. Unfortunately, this is incorrect. This patch uses function pinconf_to_config_param(config), which converts this 'config' parameter back to pinconfig to determine which option to use. Fixes: 15add06841a3 ("gpio: pca953x: add ->set_config implementation") Signed-off-by: Adam Ford <aford173@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER readMarc Zyngier4-44/+75
[ Upstream commit 9a50ebbffa9862db7604345f5fd763122b0f6fed ] When a guest tries to read the active state of its interrupts, we currently just return whatever state we have in memory. This means that if such an interrupt lives in a List Register on another CPU, we fail to obsertve the latest active state for this interrupt. In order to remedy this, stop all the other vcpus so that they exit and we can observe the most recent value for the state. This is similar to what we are doing for the write side of the same registers, and results in new MMIO handlers for userspace (which do not need to stop the guest, as it is supposed to be stopped already). Reported-by: Julien Grall <julien@xen.org> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20net: phy: microchip_t1: add lan87xx_phy_init to initialize the lan87xx phy.Yuiko Oshino1-0/+171
[ Upstream commit 63edbcceef612bdd95fa28ce100460c7b79008a4 ] lan87xx_phy_init() initializes the lan87xx phy hardware including its TC10 Wake-up and Sleep features. Fixes: 3e50d2da5850 ("Add driver for Microchip LAN87XX T1 PHYs") Signed-off-by: Yuiko Oshino <yuiko.oshino@microchip.com> v0->v1: - Add more details in the commit message and source comments. - Update to the latest initialization sequences. - Add access_ereg_modify_changed(). - Fix access_ereg() to access SMI bank correctly. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20shmem: fix possible deadlocks on shmlock_user_lockHugh Dickins1-2/+5
[ Upstream commit ea0dfeb4209b4eab954d6e00ed136bc6b48b380d ] Recent commit 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page() when punching hole") has allowed syzkaller to probe deeper, uncovering a long-standing lockdep issue between the irq-unsafe shmlock_user_lock, the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge(). user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants shmlock_user_lock while its caller shmem_lock() holds info->lock with interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock() with interrupts enabled, and might be interrupted by a writeback endio wanting xa_lock on i_pages. This may not risk an actual deadlock, since shmem inodes do not take part in writeback accounting, but there are several easy ways to avoid it. Requiring interrupts disabled for shmlock_user_lock would be easy, but it's a high-level global lock for which that seems inappropriate. Instead, recall that the use of info->lock to guard info->flags in shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode are already serialized by the caller. Take info->lock out of the chain and the possibility of deadlock or lockdep warning goes away. Fixes: 4595ef88d136 ("shmem: make shmem_inode_info::lock irq-safe") Reported-by: syzbot+c8a8197c8852f566b9d9@syzkaller.appspotmail.com Reported-by: syzbot+40b71e145e73f78f81ad@syzkaller.appspotmail.com Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Yang Shi <yang.shi@linux.alibaba.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004161707410.16322@eggly.anvils Link: https://lore.kernel.org/lkml/000000000000e5838c05a3152f53@google.com/ Link: https://lore.kernel.org/lkml/0000000000003712b305a331d3b1@google.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20net: dsa: Do not make user port errors fatalFlorian Fainelli1-7/+1
commit 86f8b1c01a0a537a73d2996615133be63cdf75db upstream. Prior to 1d27732f411d ("net: dsa: setup and teardown ports"), we would not treat failures to set-up an user port as fatal, but after this commit we would, which is a regression for some systems where interfaces may be declared in the Device Tree, but the underlying hardware may not be present (pluggable daughter cards for instance). Fixes: 1d27732f411d ("net: dsa: setup and teardown ports") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14Linux 5.4.41v5.4.41Greg Kroah-Hartman1-1/+1
2020-05-14fanotify: merge duplicate events on parent and childAmir Goldstein1-1/+6
[ Upstream commit f367a62a7cad2447d835a9f14fc63997a9137246 ] With inotify, when a watch is set on a directory and on its child, an event on the child is reported twice, once with wd of the parent watch and once with wd of the child watch without the filename. With fanotify, when a watch is set on a directory and on its child, an event on the child is reported twice, but it has the exact same information - either an open file descriptor of the child or an encoded fid of the child. The reason that the two identical events are not merged is because the object id used for merging events in the queue is the child inode in one event and parent inode in the other. For events with path or dentry data, use the victim inode instead of the watched inode as the object id for event merging, so that the event reported on parent will be merged with the event reported on the child. Link: https://lore.kernel.org/r/20200319151022.31456-9-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-14fsnotify: replace inode pointer with an object idAmir Goldstein4-9/+8
[ Upstream commit dfc2d2594e4a79204a3967585245f00644b8f838 ] The event inode field is used only for comparison in queue merges and cannot be dereferenced after handle_event(), because it does not hold a refcount on the inode. Replace it with an abstract id to do the same thing. Link: https://lore.kernel.org/r/20200319151022.31456-8-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-14bdi: add a ->dev_name field to struct backing_dev_infoChristoph Hellwig2-2/+4
[ Upstream commit 6bd87eec23cbc9ed222bed0f5b5b02bf300e9a8d ] Cache a copy of the name for the life time of the backing_dev_info structure so that we can reference it even after unregistering. Fixes: 68f23b89067f ("memcg: fix a crash in wb_workfn when a device disappears") Reported-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-14bdi: move bdi_dev_name out of lineChristoph Hellwig2-9/+10
[ Upstream commit eb7ae5e06bb6e6ac6bb86872d27c43ebab92f6b2 ] bdi_dev_name is not a fast path function, move it out of line. This prepares for using it from modular callers without having to export an implementation detail like bdi_unknown_name. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-14mm, memcg: fix error return value of mem_cgroup_css_alloc()Yafang Shao1-6/+9
commit 11d6761218d19ca06ae5387f4e3692c4fa9e7493 upstream. When I run my memcg testcase which creates lots of memcgs, I found there're unexpected out of memory logs while there're still enough available free memory. The error log is mkdir: cannot create directory 'foo.65533': Cannot allocate memory The reason is when we try to create more than MEM_CGROUP_ID_MAX memcgs, an -ENOMEM errno will be set by mem_cgroup_css_alloc(), but the right errno should be -ENOSPC "No space left on device", which is an appropriate errno for userspace's failed mkdir. As the errno really misled me, we should make it right. After this patch, the error log will be mkdir: cannot create directory 'foo.65533': No space left on device [akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal] [akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal] Fixes: 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after many small jobs") Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Link: http://lkml.kernel.org/r/20200407063621.GA18914@dhcp22.suse.cz Link: http://lkml.kernel.org/r/1586192163-20099-1-git-send-email-laoar.shao@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14scripts/decodecode: fix trapping instruction formattingIvan Delalande1-1/+1
commit e08df079b23e2e982df15aa340bfbaf50f297504 upstream. If the trapping instruction contains a ':', for a memory access through segment registers for example, the sed substitution will insert the '*' marker in the middle of the instruction instead of the line address: 2b: 65 48 0f c7 0f cmpxchg16b %gs:*(%rdi) <-- trapping instruction I started to think I had forgotten some quirk of the assembly syntax before noticing that it was actually coming from the script. Fix it to add the address marker at the right place for these instructions: 28: 49 8b 06 mov (%r14),%rax 2b:* 65 48 0f c7 0f cmpxchg16b %gs:(%rdi) <-- trapping instruction 30: 0f 94 c0 sete %al Fixes: 18ff44b189e2 ("scripts/decodecode: make faulting insn ptr more robust") Signed-off-by: Ivan Delalande <colona@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20200419223653.GA31248@visor Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14iommu/virtio: Reverse arguments to list_addJulia Lawall1-1/+1
commit fb3637a113349f53830f7d6ca45891b7192cd28f upstream. Elsewhere in the file, there is a list_for_each_entry with &vdev->resv_regions as the second argument, suggesting that &vdev->resv_regions is the list head. So exchange the arguments on the list_add call to put the list head in the second argument. Fixes: 2a5a31487445 ("iommu/virtio: Add probe request") Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Link: https://lore.kernel.org/r/1588704467-13431-1-git-send-email-Julia.Lawall@inria.fr Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-05-14objtool: Fix stack offset tracking for indirect CFAsJosh Poimboeuf1-1/+1
commit d8dd25a461e4eec7190cb9d66616aceacc5110ad upstream. When the current frame address (CFA) is stored on the stack (i.e., cfa->base == CFI_SP_INDIRECT), objtool neglects to adjust the stack offset when there are subsequent pushes or pops. This results in bad ORC data at the end of the ENTER_IRQ_STACK macro, when it puts the previous stack pointer on the stack and does a subsequent push. This fixes the following unwinder warning: WARNING: can't dereference registers at 00000000f0a6bdba for ip interrupt_entry+0x9f/0xa0 Fixes: 627fce14809b ("objtool: Add ORC unwind table generation") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Reported-by: Dave Jones <dsj@fb.com> Reported-by: Steven Rostedt <rostedt@goodmis.org> Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Joe Mario <jmario@redhat.com> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/853d5d691b29e250333332f09b8e27410b2d9924.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14netfilter: nf_osf: avoid passing pointer to local varArnd Bergmann1-5/+7
commit c165d57b552aaca607fa5daf3fb524a6efe3c5a3 upstream. gcc-10 points out that a code path exists where a pointer to a stack variable may be passed back to the caller: net/netfilter/nfnetlink_osf.c: In function 'nf_osf_hdr_ctx_init': cc1: warning: function may return address of local variable [-Wreturn-local-addr] net/netfilter/nfnetlink_osf.c:171:16: note: declared here 171 | struct tcphdr _tcph; | ^~~~~ I am not sure whether this can happen in practice, but moving the variable declaration into the callers avoids the problem. Fixes: 31a9c29210e2 ("netfilter: nf_osf: add struct nf_osf_hdr_ctx") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14netfilter: nat: never update the UDP checksum when it's 0Guillaume Nault1-3/+1
commit ea64d8d6c675c0bb712689b13810301de9d8f77a upstream. If the UDP header of a local VXLAN endpoint is NAT-ed, and the VXLAN device has disabled UDP checksums and enabled Tx checksum offloading, then the skb passed to udp_manip_pkt() has hdr->check == 0 (outer checksum disabled) and skb->ip_summed == CHECKSUM_PARTIAL (inner packet checksum offloaded). Because of the ->ip_summed value, udp_manip_pkt() tries to update the outer checksum with the new address and port, leading to an invalid checksum sent on the wire, as the original null checksum obviously didn't take the old address and port into account. So, we can't take ->ip_summed into account in udp_manip_pkt(), as it might not refer to the checksum we're acting on. Instead, we can base the decision to update the UDP checksum entirely on the value of hdr->check, because it's null if and only if checksum is disabled: * A fully computed checksum can't be 0, since a 0 checksum is represented by the CSUM_MANGLED_0 value instead. * A partial checksum can't be 0, since the pseudo-header always adds at least one non-zero value (the UDP protocol type 0x11) and adding more values to the sum can't make it wrap to 0 as the carry is then added to the wrapped number. * A disabled checksum uses the special value 0. The problem seems to be there from day one, although it was probably not visible before UDP tunnels were implemented. Fixes: 5b1158e909ec ("[NETFILTER]: Add NAT support for nf_conntrack") Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14arch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory()Janakarajan Natarajan1-1/+1
commit 996ed22c7a5251d76dcdfe5026ef8230e90066d9 upstream. When trying to lock read-only pages, sev_pin_memory() fails because FOLL_WRITE is used as the flag for get_user_pages_fast(). Commit 73b0140bf0fe ("mm/gup: change GUP fast to use flags rather than a write 'bool'") updated the get_user_pages_fast() call sites to use flags, but incorrectly updated the call in sev_pin_memory(). As the original coding of this call was correct, revert the change made by that commit. Fixes: 73b0140bf0fe ("mm/gup: change GUP fast to use flags rather than a write 'bool'") Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: Jim Mattson <jmattson@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Mike Marshall <hubcap@omnibond.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Link: http://lkml.kernel.org/r/20200423152419.87202-1-Janakarajan.Natarajan@amd.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14KVM: x86: Fixes posted interrupt check for IRQs delivery modesSuravee Suthikulpanit1-2/+2
commit 637543a8d61c6afe4e9be64bfb43c78701a83375 upstream. Current logic incorrectly uses the enum ioapic_irq_destination_types to check the posted interrupt destination types. However, the value was set using APIC_DM_XXX macros, which are left-shifted by 8 bits. Fixes by using the APIC_DM_FIXED and APIC_DM_LOWEST instead. Fixes: (fdcf75621375 'KVM: x86: Disable posted interrupts for non-standard IRQs delivery modes') Cc: Alexander Graf <graf@amazon.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Message-Id: <1586239989-58305-1-git-send-email-suravee.suthikulpanit@amd.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Tested-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/unwind/orc: Fix premature unwind stoppage due to IRET framesJosh Poimboeuf3-14/+43
commit 81b67439d147677d844d492fcbd03712ea438f42 upstream. The following execution path is possible: fsnotify() [ realign the stack and store previous SP in R10 ] <IRQ> [ only IRET regs saved ] common_interrupt() interrupt_entry() <NMI> [ full pt_regs saved ] ... [ unwind stack ] When the unwinder goes through the NMI and the IRQ on the stack, and then sees fsnotify(), it doesn't have access to the value of R10, because it only has the five IRET registers. So the unwind stops prematurely. However, because the interrupt_entry() code is careful not to clobber R10 before saving the full regs, the unwinder should be able to read R10 from the previously saved full pt_regs associated with the NMI. Handle this case properly. When encountering an IRET regs frame immediately after a full pt_regs frame, use the pt_regs as a backup which can be used to get the C register values. Also, note that a call frame resets the 'prev_regs' value, because a function is free to clobber the registers. For this fix to work, the IRET and full regs frames must be adjacent, with no FUNC frames in between. So replace the FUNC hint in interrupt_entry() with an IRET_REGS hint. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/97a408167cc09f1cfa0de31a7b70dd88868d743f.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/unwind/orc: Fix error path for bad ORC entry typeJosh Poimboeuf1-1/+1
commit a0f81bf26888048100bf017fadf438a5bdffa8d8 upstream. If the ORC entry type is unknown, nothing else can be done other than reporting an error. Exit the function instead of breaking out of the switch statement. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/a7fa668ca6eabbe81ab18b2424f15adbbfdc810a.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/unwind/orc: Prevent unwinding before ORC initializationJosh Poimboeuf1-3/+3
commit 98d0c8ebf77e0ba7c54a9ae05ea588f0e9e3f46e upstream. If the unwinder is called before the ORC data has been initialized, orc_find() returns NULL, and it tries to fall back to using frame pointers. This can cause some unexpected warnings during boot. Move the 'orc_init' check from orc_find() to __unwind_init(), so that it doesn't even try to unwind from an uninitialized state. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/069d1499ad606d85532eb32ce39b2441679667d5.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/unwind/orc: Don't skip the first frame for inactive tasksMiroslav Benes1-1/+1
commit f1d9a2abff66aa8156fbc1493abed468db63ea48 upstream. When unwinding an inactive task, the ORC unwinder skips the first frame by default. If both the 'regs' and 'first_frame' parameters of unwind_start() are NULL, 'state->sp' and 'first_frame' are later initialized to the same value for an inactive task. Given there is a "less than or equal to" comparison used at the end of __unwind_start() for skipping stack frames, the first frame is skipped. Drop the equal part of the comparison and make the behavior equivalent to the frame pointer unwinder. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/7f08db872ab59e807016910acdbe82f744de7065.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/entry/64: Fix unwind hints in rewind_stack_do_exit()Jann Horn1-1/+1
commit f977df7b7ca45a4ac4b66d30a8931d0434c394b1 upstream. The LEAQ instruction in rewind_stack_do_exit() moves the stack pointer directly below the pt_regs at the top of the task stack before calling do_exit(). Tell the unwinder to expect pt_regs. Fixes: 8c1f75587a18 ("x86/entry/64: Add unwind hint annotations") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/68c33e17ae5963854916a46f522624f8e1d264f2.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/entry/64: Fix unwind hints in kernel exit pathJosh Poimboeuf1-1/+2
commit 1fb143634a38095b641a3a21220774799772dc4c upstream. In swapgs_restore_regs_and_return_to_usermode, after the stack is switched to the trampoline stack, the existing UNWIND_HINT_REGS hint is no longer valid, which can result in the following ORC unwinder warning: WARNING: can't dereference registers at 000000003aeb0cdd for ip swapgs_restore_regs_and_return_to_usermode+0x93/0xa0 For full correctness, we could try to add complicated unwind hints so the unwinder could continue to find the registers, but when when it's this close to kernel exit, unwind hints aren't really needed anymore and it's fine to just use an empty hint which tells the unwinder to stop. For consistency, also move the UNWIND_HINT_EMPTY in entry_SYSCALL_64_after_hwframe to a similar location. Fixes: 3e3b9293d392 ("x86/entry/64: Return to userspace from the trampoline stack") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Reported-by: Dave Jones <dsj@fb.com> Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reported-by: Joe Mario <jmario@redhat.com> Reported-by: Jann Horn <jannh@google.com> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/60ea8f562987ed2d9ace2977502fe481c0d7c9a0.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14x86/entry/64: Fix unwind hints in register clearing codeJosh Poimboeuf1-19/+21
commit 06a9750edcffa808494d56da939085c35904e618 upstream. The PUSH_AND_CLEAR_REGS macro zeroes each register immediately after pushing it. If an NMI or exception hits after a register is cleared, but before the UNWIND_HINT_REGS annotation, the ORC unwinder will wrongly think the previous value of the register was zero. This can confuse the unwinding process and cause it to exit early. Because ORC is simpler than DWARF, there are a limited number of unwind annotation states, so it's not possible to add an individual unwind hint after each push/clear combination. Instead, the register clearing instructions need to be consolidated and moved to after the UNWIND_HINT_REGS annotation. Fixes: 3f01daecd545 ("x86/entry/64: Introduce the PUSH_AND_CLEAN_REGS macro") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/68fd3d0bc92ae2d62ff7879d15d3684217d51f08.1587808742.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14batman-adv: Fix refcnt leak in batadv_v_ogm_processXiyu Yang1-1/+1
commit 6f91a3f7af4186099dd10fa530dd7e0d9c29747d upstream. batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns a reference of the neighbor object to "hardif_neigh" with increased refcount. When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling paths of batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the orig node and returns NULL, the refcnt increased by batadv_hardif_neigh_get() is not decreased, causing a refcnt leak. Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get() fails to get the orig node. Fixes: 9323158ef9f4 ("batman-adv: OGMv2 - implement originators logic") Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14batman-adv: Fix refcnt leak in batadv_store_throughput_overrideXiyu Yang1-1/+1
commit 6107c5da0fca8b50b4d3215e94d619d38cc4a18c upstream. batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(), which gets a batadv_hard_iface object from net_dev with increased refcnt and its reference is assigned to a local pointer 'hard_iface'. When batadv_store_throughput_override() returns, "hard_iface" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in one error path of batadv_store_throughput_override(). When batadv_parse_throughput() returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is not decreased, causing a refcnt leak. Fix this issue by jumping to "out" label when batadv_parse_throughput() returns NULL. Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces") Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14batman-adv: Fix refcnt leak in batadv_show_throughput_overrideXiyu Yang1-0/+1
commit f872de8185acf1b48b954ba5bd8f9bc0a0d14016 upstream. batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(), which gets a batadv_hard_iface object from net_dev with increased refcnt and its reference is assigned to a local pointer 'hard_iface'. When batadv_show_throughput_override() returns, "hard_iface" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in the normal path of batadv_show_throughput_override(), which forgets to decrease the refcnt increased by batadv_hardif_get_by_netdev() before the function returns, causing a refcnt leak. Fix this issue by calling batadv_hardif_put() before the batadv_show_throughput_override() returns in the normal path. Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces") Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14batman-adv: fix batadv_nc_random_weight_tqGeorge Spelvin1-8/+1
commit fd0c42c4dea54335967c5a86f15fc064235a2797 upstream. and change to pseudorandom numbers, as this is a traffic dithering operation that doesn't need crypto-grade. The previous code operated in 4 steps: 1. Generate a random byte 0 <= rand_tq <= 255 2. Multiply it by BATADV_TQ_MAX_VALUE - tq 3. Divide by 255 (= BATADV_TQ_MAX_VALUE) 4. Return BATADV_TQ_MAX_VALUE - rand_tq This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random value between 0/255 and 255/255. But! The intermediate value between steps 3 and 4 is stored in a u8 variable. So it's truncated, and most of the time, is less than 255, after which the division produces 0. Specifically, if tq is odd, the product is always even, and can never be 255. If tq is even, there's exactly one random byte value that will produce a product byte of 255. Thus, the return value is 255 (511/512 of the time) or 254 (1/512 of the time). If we assume that the truncation is a bug, and the code is meant to scale the input, a simpler way of looking at it is that it's returning a random value between tq and BATADV_TQ_MAX_VALUE, inclusive. Well, we have an optimized function for doing just that. Fixes: 3c12de9a5c75 ("batman-adv: network coding - code and transmit packets if possible") Signed-off-by: George Spelvin <lkml@sdf.org> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14iocost: protect iocg->abs_vdebt with iocg->waitq.lockTejun Heo2-47/+77
commit 0b80f9866e6bbfb905140ed8787ff2af03652c0c upstream. abs_vdebt is an atomic_64 which tracks how much over budget a given cgroup is and controls the activation of use_delay mechanism. Once a cgroup goes over budget from forced IOs, it has to pay it back with its future budget. The progress guarantee on debt paying comes from the iocg being active - active iocgs are processed by the periodic timer, which ensures that as time passes the debts dissipate and the iocg returns to normal operation. However, both iocg activation and vdebt handling are asynchronous and a sequence like the following may happen. 1. The iocg is in the process of being deactivated by the periodic timer. 2. A bio enters ioc_rqos_throttle(), calls iocg_activate() which returns without anything because it still sees that the iocg is already active. 3. The iocg is deactivated. 4. The bio from #2 is over budget but needs to be forced. It increases abs_vdebt and goes over the threshold and enables use_delay. 5. IO control is enabled for the iocg's subtree and now IOs are attributed to the descendant cgroups and the iocg itself no longer issues IOs. This leaves the iocg with stuck abs_vdebt - it has debt but inactive and no further IOs which can activate it. This can end up unduly punishing all the descendants cgroups. The usual throttling path has the same issue - the iocg must be active while throttled to ensure that future event will wake it up - and solves the problem by synchronizing the throttling path with a spinlock. abs_vdebt handling is another form of overage handling and shares a lot of characteristics including the fact that it isn't in the hottest path. This patch fixes the above and other possible races by strictly synchronizing abs_vdebt and use_delay handling with iocg->waitq.lock. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Vlad Dmitriev <vvd@fb.com> Cc: stable@vger.kernel.org # v5.4+ Fixes: e1518f63f246 ("blk-iocost: Don't let merges push vtime into the future") Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14riscv: set max_pfn to the PFN of the last pageVincent Chen1-1/+2
commit c749bb2d554825e007cbc43b791f54e124dadfce upstream. The current max_pfn equals to zero. In this case, I found it caused users cannot get some page information through /proc such as kpagecount in v5.6 kernel because of new sanity checks. The following message is displayed by stress-ng test suite with the command "stress-ng --verbose --physpage 1 -t 1" on HiFive unleashed board. # stress-ng --verbose --physpage 1 -t 1 stress-ng: debug: [109] 4 processors online, 4 processors configured stress-ng: info: [109] dispatching hogs: 1 physpage stress-ng: debug: [109] cache allocate: reducing cache level from L3 (too high) to L0 stress-ng: debug: [109] get_cpu_cache: invalid cache_level: 0 stress-ng: info: [109] cache allocate: using built-in defaults as no suitable cache found stress-ng: debug: [109] cache allocate: default cache size: 2048K stress-ng: debug: [109] starting stressors stress-ng: debug: [109] 1 stressor spawned stress-ng: debug: [110] stress-ng-physpage: started [110] (instance 0) stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd34de000 in /proc/kpagecount, errno=0 (Success) stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success) ... stress-ng: error: [110] stress-ng-physpage: cannot read page count for address 0x3fd32db078 in /proc/kpagecount, errno=0 (Success) stress-ng: debug: [110] stress-ng-physpage: exited [110] (instance 0) stress-ng: debug: [109] process [110] terminated stress-ng: info: [109] successful run completed in 1.00s # After applying this patch, the kernel can pass the test. # stress-ng --verbose --physpage 1 -t 1 stress-ng: debug: [104] 4 processors online, 4 processors configured stress-ng: info: [104] dispatching hogs: 1 physpage stress-ng: info: [104] cache allocate: using defaults, can't determine cache details from sysfs stress-ng: debug: [104] cache allocate: default cache size: 2048K stress-ng: debug: [104] starting stressors stress-ng: debug: [104] 1 stressor spawned stress-ng: debug: [105] stress-ng-physpage: started [105] (instance 0) stress-ng: debug: [105] stress-ng-physpage: exited [105] (instance 0) stress-ng: debug: [104] process [105] terminated stress-ng: info: [104] successful run completed in 1.01s # Cc: stable@vger.kernel.org Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Yash Shah <yash.shah@sifive.com> Tested-by: Yash Shah <yash.shah@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14coredump: fix crash when umh is disabledLuis Chamberlain2-0/+13
commit 3740d93e37902b31159a82da2d5c8812ed825404 upstream. Commit 64e90a8acb859 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()") added the optiont to disable all call_usermodehelper() calls by setting STATIC_USERMODEHELPER_PATH to an empty string. When this is done, and crashdump is triggered, it will crash on null pointer dereference, since we make assumptions over what call_usermodehelper_exec() did. This has been reported by Sergey when one triggers a a coredump with the following configuration: ``` CONFIG_STATIC_USERMODEHELPER=y CONFIG_STATIC_USERMODEHELPER_PATH="" kernel.core_pattern = |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %e ``` The way disabling the umh was designed was that call_usermodehelper_exec() would just return early, without an error. But coredump assumes certain variables are set up for us when this happens, and calls ile_start_write(cprm.file) with a NULL file. [ 2.819676] BUG: kernel NULL pointer dereference, address: 0000000000000020 [ 2.819859] #PF: supervisor read access in kernel mode [ 2.820035] #PF: error_code(0x0000) - not-present page [ 2.820188] PGD 0 P4D 0 [ 2.820305] Oops: 0000 [#1] SMP PTI [ 2.820436] CPU: 2 PID: 89 Comm: a Not tainted 5.7.0-rc1+ #7 [ 2.820680] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014 [ 2.821150] RIP: 0010:do_coredump+0xd80/0x1060 [ 2.821385] Code: e8 95 11 ed ff 48 c7 c6 cc a7 b4 81 48 8d bd 28 ff ff ff 89 c2 e8 70 f1 ff ff 41 89 c2 85 c0 0f 84 72 f7 ff ff e9 b4 fe ff ff <48> 8b 57 20 0f b7 02 66 25 00 f0 66 3d 00 8 0 0f 84 9c 01 00 00 44 [ 2.822014] RSP: 0000:ffffc9000029bcb8 EFLAGS: 00010246 [ 2.822339] RAX: 0000000000000000 RBX: ffff88803f860000 RCX: 000000000000000a [ 2.822746] RDX: 0000000000000009 RSI: 0000000000000282 RDI: 0000000000000000 [ 2.823141] RBP: ffffc9000029bde8 R08: 0000000000000000 R09: ffffc9000029bc00 [ 2.823508] R10: 0000000000000001 R11: ffff88803dec90be R12: ffffffff81c39da0 [ 2.823902] R13: ffff88803de84400 R14: 0000000000000000 R15: 0000000000000000 [ 2.824285] FS: 00007fee08183540(0000) GS:ffff88803e480000(0000) knlGS:0000000000000000 [ 2.824767] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.825111] CR2: 0000000000000020 CR3: 000000003f856005 CR4: 0000000000060ea0 [ 2.825479] Call Trace: [ 2.825790] get_signal+0x11e/0x720 [ 2.826087] do_signal+0x1d/0x670 [ 2.826361] ? force_sig_info_to_task+0xc1/0xf0 [ 2.826691] ? force_sig_fault+0x3c/0x40 [ 2.826996] ? do_trap+0xc9/0x100 [ 2.827179] exit_to_usermode_loop+0x49/0x90 [ 2.827359] prepare_exit_to_usermode+0x77/0xb0 [ 2.827559] ? invalid_op+0xa/0x30 [ 2.827747] ret_from_intr+0x20/0x20 [ 2.827921] RIP: 0033:0x55e2c76d2129 [ 2.828107] Code: 2d ff ff ff e8 68 ff ff ff 5d c6 05 18 2f 00 00 01 c3 0f 1f 80 00 00 00 00 c3 0f 1f 80 00 00 00 00 e9 7b ff ff ff 55 48 89 e5 <0f> 0b b8 00 00 00 00 5d c3 66 2e 0f 1f 84 0 0 00 00 00 00 0f 1f 40 [ 2.828603] RSP: 002b:00007fffeba5e080 EFLAGS: 00010246 [ 2.828801] RAX: 000055e2c76d2125 RBX: 0000000000000000 RCX: 00007fee0817c718 [ 2.829034] RDX: 00007fffeba5e188 RSI: 00007fffeba5e178 RDI: 0000000000000001 [ 2.829257] RBP: 00007fffeba5e080 R08: 0000000000000000 R09: 00007fee08193c00 [ 2.829482] R10: 0000000000000009 R11: 0000000000000000 R12: 000055e2c76d2040 [ 2.829727] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 2.829964] CR2: 0000000000000020 [ 2.830149] ---[ end trace ceed83d8c68a1bf1 ]--- ``` Cc: <stable@vger.kernel.org> # v4.11+ Fixes: 64e90a8acb85 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()") BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199795 Reported-by: Tony Vroon <chainsaw@gentoo.org> Reported-by: Sergey Kvachonok <ravenexp@gmail.com> Tested-by: Sergei Trofimovich <slyfox@gentoo.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20200416162859.26518-1-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14staging: gasket: Check the return value of gasket_get_bar_index()Oscar Carter1-0/+4
commit 769acc3656d93aaacada814939743361d284fd87 upstream. Check the return value of gasket_get_bar_index function as it can return a negative one (-EINVAL). If this happens, a negative index is used in the "gasket_dev->bar_data" array. Addresses-Coverity-ID: 1438542 ("Negative array index read") Fixes: 9a69f5087ccc2 ("drivers/staging: Gasket driver framework + Apex driver") Signed-off-by: Oscar Carter <oscar.carter@gmx.com> Cc: stable <stable@vger.kernel.org> Reviewed-by: Richard Yeh <rcy@google.com> Link: https://lore.kernel.org/r/20200501155118.13380-1-oscar.carter@gmx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14ceph: demote quotarealm lookup warning to a debug messageLuis Henriques1-2/+2
commit 12ae44a40a1be891bdc6463f8c7072b4ede746ef upstream. A misconfigured cephx can easily result in having the kernel client flooding the logs with: ceph: Can't lookup inode 1 (err: -13) Change this message to debug level. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/44546 Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14ceph: fix endianness bug when handling MDS session feature bitsJeff Layton1-5/+3
commit 0fa8263367db9287aa0632f96c1a5f93cc478150 upstream. Eduard reported a problem mounting cephfs on s390 arch. The feature mask sent by the MDS is little-endian, so we need to convert it before storing and testing against it. Cc: stable@vger.kernel.org Reported-and-Tested-by: Eduard Shishkin <edward6@linux.ibm.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14mm: limit boost_watermark on small zonesHenry Willard1-0/+8
commit 14f69140ff9c92a0928547ceefb153a842e8492c upstream. Commit 1c30844d2dfe ("mm: reclaim small amounts of memory when an external fragmentation event occurs") adds a boost_watermark() function which increases the min watermark in a zone by at least pageblock_nr_pages or the number of pages in a page block. On Arm64, with 64K pages and 512M huge pages, this is 8192 pages or 512M. It does this regardless of the number of managed pages managed in the zone or the likelihood of success. This can put the zone immediately under water in terms of allocating pages from the zone, and can cause a small machine to fail immediately due to OoM. Unlike set_recommended_min_free_kbytes(), which substantially increases min_free_kbytes and is tied to THP, boost_watermark() can be called even if THP is not active. The problem is most likely to appear on architectures such as Arm64 where pageblock_nr_pages is very large. It is desirable to run the kdump capture kernel in as small a space as possible to avoid wasting memory. In some architectures, such as Arm64, there are restrictions on where the capture kernel can run, and therefore, the space available. A capture kernel running in 768M can fail due to OoM immediately after boost_watermark() sets the min in zone DMA32, where most of the memory is, to 512M. It fails even though there is over 500M of free memory. With boost_watermark() suppressed, the capture kernel can run successfully in 448M. This patch limits boost_watermark() to boosting a zone's min watermark only when there are enough pages that the boost will produce positive results. In this case that is estimated to be four times as many pages as pageblock_nr_pages. Mel said: : There is no harm in marking it stable. Clearly it does not happen very : often but it's not impossible. 32-bit x86 is a lot less common now : which would previously have been vulnerable to triggering this easily. : ppc64 has a larger base page size but typically only has one zone. : arm64 is likely the most vulnerable, particularly when CMA is : configured with a small movable zone. Fixes: 1c30844d2dfe ("mm: reclaim small amounts of memory when an external fragmentation event occurs") Signed-off-by: Henry Willard <henry.willard@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1588294148-6586-1-git-send-email-henry.willard@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14mm/page_alloc: fix watchdog soft lockups during set_zone_contiguous()David Hildenbrand1-0/+1
commit e84fe99b68ce353c37ceeecc95dce9696c976556 upstream. Without CONFIG_PREEMPT, it can happen that we get soft lockups detected, e.g., while booting up. watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-next-20200331+ #4 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: __pageblock_pfn_to_page+0x134/0x1c0 Call Trace: set_zone_contiguous+0x56/0x70 page_alloc_init_late+0x166/0x176 kernel_init_freeable+0xfa/0x255 kernel_init+0xa/0x106 ret_from_fork+0x35/0x40 The issue becomes visible when having a lot of memory (e.g., 4TB) assigned to a single NUMA node - a system that can easily be created using QEMU. Inside VMs on a hypervisor with quite some memory overcommit, this is fairly easy to trigger. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Shile Zhang <shile.zhang@linux.alibaba.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Alexander Duyck <alexander.duyck@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200416073417.5003-1-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14eventpoll: fix missing wakeup for ovflist in ep_poll_callbackKhazhismel Kumykov1-9/+9
commit 0c54a6a44bf3d41e76ce3f583a6ece267618df2e upstream. In the event that we add to ovflist, before commit 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") we would be woken up by ep_scan_ready_list, and did no wakeup in ep_poll_callback. With that wakeup removed, if we add to ovflist here, we may never wake up. Rather than adding back the ep_scan_ready_list wakeup - which was resulting in unnecessary wakeups, trigger a wake-up in ep_poll_callback. We noticed that one of our workloads was missing wakeups starting with 339ddb53d373 and upon manual inspection, this wakeup seemed missing to me. With this patch added, we no longer see missing wakeups. I haven't yet tried to make a small reproducer, but the existing kselftests in filesystem/epoll passed for me with this patch. [khazhy@google.com: use if/elif instead of goto + cleanup suggested by Roman] Link: http://lkml.kernel.org/r/20200424190039.192373-1-khazhy@google.com Fixes: 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") Signed-off-by: Khazhismel Kumykov <khazhy@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Roman Penyaev <rpenyaev@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Roman Penyaev <rpenyaev@suse.de> Cc: Heiher <r@hev.cc> Cc: Jason Baron <jbaron@akamai.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200424025057.118641-1-khazhy@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14epoll: atomically remove wait entry on wake upRoman Penyaev1-19/+24
commit 412895f03cbf9633298111cb4dfde13b7720e2c5 upstream. This patch does two things: - fixes a lost wakeup introduced by commit 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") - improves performance for events delivery. The description of the problem is the following: if N (>1) threads are waiting on ep->wq for new events and M (>1) events come, it is quite likely that >1 wakeups hit the same wait queue entry, because there is quite a big window between __add_wait_queue_exclusive() and the following __remove_wait_queue() calls in ep_poll() function. This can lead to lost wakeups, because thread, which was woken up, can handle not all the events in ->rdllist. (in better words the problem is described here: https://lkml.org/lkml/2019/10/7/905) The idea of the current patch is to use init_wait() instead of init_waitqueue_entry(). Internally init_wait() sets autoremove_wake_function as a callback, which removes the wait entry atomically (under the wq locks) from the list, thus the next coming wakeup hits the next wait entry in the wait queue, thus preventing lost wakeups. Problem is very well reproduced by the epoll60 test case [1]. Wait entry removal on wakeup has also performance benefits, because there is no need to take a ep->lock and remove wait entry from the queue after the successful wakeup. Here is the timing output of the epoll60 test case: With explicit wakeup from ep_scan_ready_list() (the state of the code prior 339ddb53d373): real 0m6.970s user 0m49.786s sys 0m0.113s After this patch: real 0m5.220s user 0m36.879s sys 0m0.019s The other testcase is the stress-epoll [2], where one thread consumes all the events and other threads produce many events: With explicit wakeup from ep_scan_ready_list() (the state of the code prior 339ddb53d373): threads events/ms run-time ms 8 5427 1474 16 6163 2596 32 6824 4689 64 7060 9064 128 6991 18309 After this patch: threads events/ms run-time ms 8 5598 1429 16 7073 2262 32 7502 4265 64 7640 8376 128 7634 16767 (number of "events/ms" represents event bandwidth, thus higher is better; number of "run-time ms" represents overall time spent doing the benchmark, thus lower is better) [1] tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c [2] https://github.com/rouming/test-tools/blob/master/stress-epoll.c Signed-off-by: Roman Penyaev <rpenyaev@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jason Baron <jbaron@akamai.com> Cc: Khazhismel Kumykov <khazhy@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Heiher <r@hev.cc> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200430130326.1368509-2-rpenyaev@suse.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()Oleg Nesterov1-8/+26
commit b5f2006144c6ae941726037120fa1001ddede784 upstream. Commit cc731525f26a ("signal: Remove kernel interal si_code magic") changed the value of SI_FROMUSER(SI_MESGQ), this means that mq_notify() no longer works if the sender doesn't have rights to send a signal. Change __do_notify() to use do_send_sig_info() instead of kill_pid_info() to avoid check_kill_permission(). This needs the additional notify.sigev_signo != 0 check, shouldn't we change do_mq_notify() to deny sigev_signo == 0 ? Test-case: #include <signal.h> #include <mqueue.h> #include <unistd.h> #include <sys/wait.h> #include <assert.h> static int notified; static void sigh(int sig) { notified = 1; } int main(void) { signal(SIGIO, sigh); int fd = mq_open("/mq", O_RDWR|O_CREAT, 0666, NULL); assert(fd >= 0); struct sigevent se = { .sigev_notify = SIGEV_SIGNAL, .sigev_signo = SIGIO, }; assert(mq_notify(fd, &se) == 0); if (!fork()) { assert(setuid(1) == 0); mq_send(fd, "",1,0); return 0; } wait(NULL); mq_unlink("/mq"); assert(notified); return 0; } [manfred@colorfullife.com: 1) Add self_exec_id evaluation so that the implementation matches do_notify_parent 2) use PIDTYPE_TGID everywhere] Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic") Reported-by: Yoji <yoji.fujihar.min@gmail.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Markus Elfring <elfring@users.sourceforge.net> Cc: <1vier1@web.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/e2a782e4-eab9-4f5c-c749-c07a8f7a4e66@colorfullife.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14drm: ingenic-drm: add MODULE_DEVICE_TABLEH. Nikolaus Schaller1-0/+1
commit c59359a02d14a7256cd508a4886b7d2012df2363 upstream. so that the driver can load by matching the device tree if compiled as module. Cc: stable@vger.kernel.org # v5.3+ Fixes: 90b86fcc47b4 ("DRM: Add KMS driver for the Ingenic JZ47xx SoCs") Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com> Signed-off-by: Paul Cercueil <paul@crapouillou.net> Link: https://patchwork.freedesktop.org/patch/msgid/1694a29b7a3449b6b662cec33d1b33f2ee0b174a.1588574111.git.hns@goldelico.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14arm64: hugetlb: avoid potential NULL dereferenceMark Rutland1-0/+2
commit 027d0c7101f50cf03aeea9eebf484afd4920c8d3 upstream. The static analyzer in GCC 10 spotted that in huge_pte_alloc() we may pass a NULL pmdp into pte_alloc_map() when pmd_alloc() returns NULL: | CC arch/arm64/mm/pageattr.o | CC arch/arm64/mm/hugetlbpage.o | from arch/arm64/mm/hugetlbpage.c:10: | arch/arm64/mm/hugetlbpage.c: In function ‘huge_pte_alloc’: | ./arch/arm64/include/asm/pgtable-types.h:28:24: warning: dereference of NULL ‘pmdp’ [CWE-690] [-Wanalyzer-null-dereference] | ./arch/arm64/include/asm/pgtable.h:436:26: note: in expansion of macro ‘pmd_val’ | arch/arm64/mm/hugetlbpage.c:242:10: note: in expansion of macro ‘pte_alloc_map’ | |arch/arm64/mm/hugetlbpage.c:232:10: | |./arch/arm64/include/asm/pgtable-types.h:28:24: | ./arch/arm64/include/asm/pgtable.h:436:26: note: in expansion of macro ‘pmd_val’ | arch/arm64/mm/hugetlbpage.c:242:10: note: in expansion of macro ‘pte_alloc_map’ This can only occur when the kernel cannot allocate a page, and so is unlikely to happen in practice before other systems start failing. We can avoid this by bailing out if pmd_alloc() fails, as we do earlier in the function if pud_alloc() fails. Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Kyrill Tkachov <kyrylo.tkachov@arm.com> Cc: <stable@vger.kernel.org> # 4.5.x- Cc: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14KVM: arm64: Fix 32bit PC wrap-aroundMarc Zyngier2-2/+13
commit 0225fd5e0a6a32af7af0aefac45c8ebf19dc5183 upstream. In the unlikely event that a 32bit vcpu traps into the hypervisor on an instruction that is located right at the end of the 32bit range, the emulation of that instruction is going to increment PC past the 32bit range. This isn't great, as userspace can then observe this value and get a bit confused. Conversly, userspace can do things like (in the context of a 64bit guest that is capable of 32bit EL0) setting PSTATE to AArch64-EL0, set PC to a 64bit value, change PSTATE to AArch32-USR, and observe that PC hasn't been truncated. More confusion. Fix both by: - truncating PC increments for 32bit guests - sanitizing all 32bit regs every time a core reg is changed by userspace, and that PSTATE indicates a 32bit mode. Cc: stable@vger.kernel.org Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>