kernel/linux.git, branch v4.4.143

Linux 4.4.143

2018-07-22T12:25:54+00:00

net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL.

2018-07-22T12:25:54+00:00

commit 3bc53be9db21040b5d2de4d455f023c8c494aa68 upstream. syzbot is reporting stalls at nfc_llcp_send_ui_frame() [1]. This is because nfc_llcp_send_ui_frame() is retrying the loop without any delay when nonblocking nfc_alloc_send_skb() returned NULL. Since there is no need to use MSG_DONTWAIT if we retry until sock_alloc_send_pskb() succeeds, let's use blocking call. Also, in case an unexpected error occurred, let's break the loop if blocking nfc_alloc_send_skb() failed. [1] https://syzkaller.appspot.com/bug?id=4a131cc571c3733e0eff6bc673f4e36ae48f19c6 Signed-off-by: Tetsuo Handa Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

rds: avoid unenecessary cong_update in loop transport

2018-07-22T12:25:54+00:00

commit f1693c63ab133d16994cc50f773982b5905af264 upstream. Loop transport which is self loopback, remote port congestion update isn't relevant. Infact the xmit path already ignores it. Receive path needs to do the same. Reported-by: syzbot+4c20b3866171ce8441d2@syzkaller.appspotmail.com Reviewed-by: Sowmini Varadhan Signed-off-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

KEYS: DNS: fix parsing multiple options

2018-07-22T12:25:54+00:00

commit c604cb767049b78b3075497b80ebb8fd530ea2cc upstream. My recent fix for dns_resolver_preparse() printing very long strings was incomplete, as shown by syzbot which still managed to hit the WARN_ONCE() in set_precision() by adding a crafted "dns_resolver" key: precision 50001 too large WARNING: CPU: 7 PID: 864 at lib/vsprintf.c:2164 vsnprintf+0x48a/0x5a0 The bug this time isn't just a printing bug, but also a logical error when multiple options ("#"-separated strings) are given in the key payload. Specifically, when separating an option string into name and value, if there is no value then the name is incorrectly considered to end at the end of the key payload, rather than the end of the current option. This bypasses validation of the option length, and also means that specifying multiple options is broken -- which presumably has gone unnoticed as there is currently only one valid option anyway. A similar problem also applied to option values, as the kstrtoul() when parsing the "dnserror" option will read past the end of the current option and into the next option. Fix these bugs by correctly computing the length of the option name and by copying the option value, null-terminated, into a temporary buffer. Reproducer for the WARN_ONCE() that syzbot hit: perl -e 'print "#A#", "\0" x 50000' | keyctl padd dns_resolver desc @s Reproducer for "dnserror" option being parsed incorrectly (expected behavior is to fail when seeing the unknown option "foo", actual behavior was to read the dnserror value as "1#foo" and fail there): perl -e 'print "#dnserror=1#foo\0"' | keyctl padd dns_resolver desc @s Reported-by: syzbot Fixes: 4a2d789267e0 ("DNS: If the DNS server returns an error, allow that to be cached [ver #2]") Signed-off-by: Eric Biggers Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

netfilter: ebtables: reject non-bridge targets

2018-07-22T12:25:54+00:00

commit 11ff7288beb2b7da889a014aff0a7b80bf8efcf3 upstream. the ebtables evaluation loop expects targets to return positive values (jumps), or negative values (absolute verdicts). This is completely different from what xtables does. In xtables, targets are expected to return the standard netfilter verdicts, i.e. NF_DROP, NF_ACCEPT, etc. ebtables will consider these as jumps. Therefore reject any target found due to unspec fallback. v2: also reject watchers. ebtables ignores their return value, so a target that assumes skb ownership (and returns NF_STOLEN) causes use-after-free. The only watchers in the 'ebtables' front-end are log and nflog; both have AF_BRIDGE specific wrappers on kernel side. Reported-by: syzbot+2b43f681169a2a0d306a@syzkaller.appspotmail.com Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

MIPS: Use async IPIs for arch_trigger_cpumask_backtrace()

2018-07-22T12:25:54+00:00

commit b63e132b6433a41cf311e8bc382d33fd2b73b505 upstream. The current MIPS implementation of arch_trigger_cpumask_backtrace() is broken because it attempts to use synchronous IPIs despite the fact that it may be run with interrupts disabled. This means that when arch_trigger_cpumask_backtrace() is invoked, for example by the RCU CPU stall watchdog, we may: - Deadlock due to use of synchronous IPIs with interrupts disabled, causing the CPU that's attempting to generate the backtrace output to hang itself. - Not succeed in generating the desired output from remote CPUs. - Produce warnings about this from smp_call_function_many(), for example: [42760.526910] INFO: rcu_sched detected stalls on CPUs/tasks: [42760.535755] 0-...!: (1 GPs behind) idle=ade/140000000000000/0 softirq=526944/526945 fqs=0 [42760.547874] 1-...!: (0 ticks this GP) idle=e4a/140000000000000/0 softirq=547885/547885 fqs=0 [42760.559869] (detected by 2, t=2162 jiffies, g=266689, c=266688, q=33) [42760.568927] ------------[ cut here ]------------ [42760.576146] WARNING: CPU: 2 PID: 1216 at kernel/smp.c:416 smp_call_function_many+0x88/0x20c [42760.587839] Modules linked in: [42760.593152] CPU: 2 PID: 1216 Comm: sh Not tainted 4.15.4-00373-gee058bb4d0c2 #2 [42760.603767] Stack : 8e09bd20 8e09bd20 8e09bd20 fffffff0 00000007 00000006 00000000 8e09bca8 [42760.616937] 95b2b379 95b2b379 807a0080 00000007 81944518 0000018a 00000032 00000000 [42760.630095] 00000000 00000030 80000000 00000000 806eca74 00000009 8017e2b8 000001a0 [42760.643169] 00000000 00000002 00000000 8e09baa4 00000008 808b8008 86d69080 8e09bca0 [42760.656282] 8e09ad50 805e20aa 00000000 00000000 00000000 8017e2b8 00000009 801070ca [42760.669424] ... [42760.673919] Call Trace: [42760.678672] [<27fde568>] show_stack+0x70/0xf0 [42760.685417] [<84751641>] dump_stack+0xaa/0xd0 [42760.692188] [<699d671c>] __warn+0x80/0x92 [42760.698549] [<68915d41>] warn_slowpath_null+0x28/0x36 [42760.705912] [] smp_call_function_many+0x88/0x20c [42760.713696] [<6bbdfc2a>] arch_trigger_cpumask_backtrace+0x30/0x4a [42760.722216] [] rcu_dump_cpu_stacks+0x6a/0x98 [42760.729580] [<796e7629>] rcu_check_callbacks+0x672/0x6ac [42760.737476] [<059b3b43>] update_process_times+0x18/0x34 [42760.744981] [<6eb94941>] tick_sched_handle.isra.5+0x26/0x38 [42760.752793] [<478d3d70>] tick_sched_timer+0x1c/0x50 [42760.759882] [] __hrtimer_run_queues+0xc6/0x226 [42760.767418] [] hrtimer_interrupt+0x88/0x19a [42760.775031] [<6765a19e>] gic_compare_interrupt+0x2e/0x3a [42760.782761] [<0558bf5f>] handle_percpu_devid_irq+0x78/0x168 [42760.790795] [<90c11ba2>] generic_handle_irq+0x1e/0x2c [42760.798117] [<1b6d462c>] gic_handle_local_int+0x38/0x86 [42760.805545] [] gic_irq_dispatch+0xa/0x14 [42760.812534] [<90c11ba2>] generic_handle_irq+0x1e/0x2c [42760.820086] [] do_IRQ+0x16/0x20 [42760.826274] [<9aef3ce6>] plat_irq_dispatch+0x62/0x94 [42760.833458] [<6a94b53c>] except_vec_vi_end+0x70/0x78 [42760.840655] [<22284043>] smp_call_function_many+0x1ba/0x20c [42760.848501] [<54022b58>] smp_call_function+0x1e/0x2c [42760.855693] [] flush_tlb_mm+0x2a/0x98 [42760.862730] [<0844cdd0>] tlb_flush_mmu+0x1c/0x44 [42760.869628] [] arch_tlb_finish_mmu+0x26/0x3e [42760.877021] [<1aeaaf74>] tlb_finish_mmu+0x18/0x66 [42760.883907] [] exit_mmap+0x76/0xea [42760.890428] [] mmput+0x80/0x11a [42760.896632] [] do_exit+0x1f4/0x80c [42760.903158] [] do_group_exit+0x20/0x7e [42760.909990] [<13fa8d54>] __wake_up_parent+0x0/0x1e [42760.917045] [<46cf89d0>] smp_call_function_many+0x1a2/0x20c [42760.924893] [<8c21a93b>] syscall_common+0x14/0x1c [42760.931765] ---[ end trace 02aa09da9dc52a60 ]--- [42760.938342] ------------[ cut here ]------------ [42760.945311] WARNING: CPU: 2 PID: 1216 at kernel/smp.c:291 smp_call_function_single+0xee/0xf8 ... This patch switches MIPS' arch_trigger_cpumask_backtrace() to use async IPIs & smp_call_function_single_async() in order to resolve this problem. We ensure use of the pre-allocated call_single_data_t structures is serialized by maintaining a cpumask indicating that they're busy, and refusing to attempt to send an IPI when a CPU's bit is set in this mask. This should only happen if a CPU hasn't responded to a previous backtrace IPI - ie. if it's hung - and we print a warning to the console in this case. I've marked this for stable branches as far back as v4.9, to which it applies cleanly. Strictly speaking the faulty MIPS implementation can be traced further back to commit 856839b76836 ("MIPS: Add arch_trigger_all_cpu_backtrace() function") in v3.19, but kernel versions v3.19 through v4.8 will require further work to backport due to the rework performed in commit 9a01c3ed5cdb ("nmi_backtrace: add more trigger_*_cpu_backtrace() methods"). Signed-off-by: Paul Burton Patchwork: https://patchwork.linux-mips.org/patch/19597/ Cc: James Hogan Cc: Ralf Baechle Cc: Huacai Chen Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # v4.9+ Fixes: 856839b76836 ("MIPS: Add arch_trigger_all_cpu_backtrace() function") Fixes: 9a01c3ed5cdb ("nmi_backtrace: add more trigger_*_cpu_backtrace() methods") [ Huacai: backported to 4.4: Restruction since generic NMI solution is unavailable ] Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

MIPS: Call dump_stack() from show_regs()

2018-07-22T12:25:53+00:00

commit 5a267832c2ec47b2dad0fdb291a96bb5b8869315 upstream. The generic nmi_cpu_backtrace() function calls show_regs() when a struct pt_regs is available, and dump_stack() otherwise. If we were to make use of the generic nmi_cpu_backtrace() with MIPS' current implementation of show_regs() this would mean that we see only register data with no accompanying stack information, in contrast with our current implementation which calls dump_stack() regardless of whether register state is available. In preparation for making use of the generic nmi_cpu_backtrace() to implement arch_trigger_cpumask_backtrace(), have our implementation of show_regs() call dump_stack() and drop the explicit dump_stack() call in arch_dump_stack() which is invoked by arch_trigger_cpumask_backtrace(). This will allow the output we produce to remain the same after a later patch switches to using nmi_cpu_backtrace(). It may mean that we produce extra stack output in other uses of show_regs(), but this: 1) Seems harmless. 2) Is good for consistency between arch_trigger_cpumask_backtrace() and other users of show_regs(). 3) Matches the behaviour of the ARM & PowerPC architectures. Marked for stable back to v4.9 as a prerequisite of the following patch "MIPS: Call dump_stack() from show_regs()". Signed-off-by: Paul Burton Patchwork: https://patchwork.linux-mips.org/patch/19596/ Cc: James Hogan Cc: Ralf Baechle Cc: Huacai Chen Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

rtlwifi: rtl8821ae: fix firmware is not ready to run

2018-07-22T12:25:53+00:00

commit 9a98302de19991d51e067b88750585203b2a3ab6 upstream. Without this patch, firmware will not run properly on rtl8821ae, and it causes bad user experience. For example, bad connection performance with low rate, higher power consumption, and so on. rtl8821ae uses two kinds of firmwares for normal and WoWlan cases, and each firmware has firmware data buffer and size individually. Original code always overwrite size of normal firmware rtlpriv->rtlhal.fwsize, and this mismatch causes firmware checksum error, then firmware can't start. In this situation, driver gives message "Firmware is not ready to run!". Fixes: fe89707f0afa ("rtlwifi: rtl8821ae: Simplify loading of WOWLAN firmware") Signed-off-by: Ping-Ke Shih Cc: Stable # 4.0+ Reviewed-by: Larry Finger Signed-off-by: Kalle Valo Signed-off-by: Greg Kroah-Hartman

net: cxgb3_main: fix potential Spectre v1

2018-07-22T12:25:53+00:00

commit 676bcfece19f83621e905aa55b5ed2d45cc4f2d3 upstream. t.qset_idx can be indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c:2286 cxgb_extension_ioctl() warn: potential spectre issue 'adapter->msix_info' Fix this by sanitizing t.qset_idx before using it to index adapter->msix_info Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/mlx5: Fix command interface race in polling mode

2018-07-22T12:25:53+00:00

[ Upstream commit d412c31dae053bf30a1bc15582a9990df297a660 ] The command interface can work in two modes: Events and Polling. In the general case, each time we invoke a command, a work is queued to handle it. When working in events, the interrupt handler completes the command execution. On the other hand, when working in polling mode, the work itself completes it. Due to a bug in the work handler, a command could have been completed by the interrupt handler, while the work handler hasn't finished yet, causing the it to complete once again if the command interface mode was changed from Events to polling after the interrupt handler was called. mlx5_unload_one() mlx5_stop_eqs() // Destroy the EQ before cmd EQ ...cmd_work_handler() write_doorbell() --> EVENT_TYPE_CMD mlx5_cmd_comp_handler() // First free free_ent(cmd, ent->idx) complete(&ent->done) <-- mlx5_stop_eqs //cmd was complete // move to polling before destroying the last cmd EQ mlx5_cmd_use_polling() cmd->mode = POLL; --> cmd_work_handler (continues) if (cmd->mode == POLL) mlx5_cmd_comp_handler() // Double free The solution is to store the cmd->mode before writing the doorbell. Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Signed-off-by: Alex Vesker Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman