- 13 Sep, 2015 19 commits
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Greg Kroah-Hartman authored
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Marc Zyngier authored
commit 126c69a0 upstream. When injecting a fault into a misbehaving 32bit guest, it seems rather idiotic to also inject a 64bit fault that is only going to corrupt the guest state. This leads to a situation where we perform an illegal exception return at EL2 causing the host to crash instead of killing the guest. Just fix the stupid bug that has been there from day 1. Reported-by:
Russell King <rmk+kernel@arm.linux.org.uk> Tested-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Alan Stern authored
commit 49718f0f upstream. The routines in scsi_rpm.c assume that if a runtime-PM callback is invoked for a SCSI device, it can only mean that the device's driver has asked the block layer to handle the runtime power management (by calling blk_pm_runtime_init(), which among other things sets q->dev). However, this assumption turns out to be wrong for things like the ses driver. Normally ses devices are not allowed to do runtime PM, but userspace can override this setting. If this happens, the kernel gets a NULL pointer dereference when blk_post_runtime_resume() tries to use the uninitialized q->dev pointer. This patch fixes the problem by calling the block layer's runtime-PM routines only if the device's driver really does have a runtime-PM callback routine. Since ses doesn't define any such callbacks, the crash won't occur. This fixes Bugzilla #101371. Signed-off-by:
Alan Stern <stern@rowland.harvard.edu> Reported-by:
Stanisław Pitucha <viraptor@gmail.com> Reported-by:
Ilan Cohen <ilanco@gmail.com> Tested-by:
Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by:
James Bottomley <JBottomley@Odin.com> Signed-off-by:
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Yann Droneaud authored
commit d6c763af upstream. Since commit 8a0a9bd4 ('random: make get_random_int() more random'), get_random_int() returns a random value for each call, so comment and hack introduced in mmap_rnd() as part of commit 1d18c47c ('arm64: MMU fault handling and page table management') are incorrects. Commit 1d18c47c seems to use the same hack introduced by commit a5adc91a ('powerpc: Ensure random space between stack and mmaps'), latter copied in commit 5a0efea0 ('sparc64: Sharpen address space randomization calculations.'). But both architectures were cleaned up as part of commit fa8cbaaf ('powerpc+sparc64/mm: Remove hack in mmap randomize layout') as hack is no more needed since commit 8a0a9bd4. So the present patch removes the comment and the hack around get_random_int() on AArch64's mmap_rnd(). Cc: David S. Miller <davem@davemloft.net> Cc: Anton Blanchard <anton@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by:
Dan McGee <dpmcgee@gmail.com> Signed-off-by:
Yann Droneaud <ydroneaud@opteya.com> Signed-off-by:
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Horia Geant? authored
commit b310c178 upstream. When doing pointer operation for accessing the HW S/G table, a value representing number of entries (and not number of bytes) must be used. Fixes: 045e3678 ("crypto: caam - ahash hmac support") Signed-off-by:
Horia Geant? <horia.geanta@freescale.com> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Guenter Roeck authored
commit 8ef9724b upstream. When inserting a new register into a block, the present bit map size is increased using krealloc. krealloc does not clear the additionally allocated memory, leaving it filled with random values. Result is that some registers are considered cached even though this is not the case. Fix the problem by clearing the additionally allocated memory. Also, if the bitmap size does not increase, do not reallocate the bitmap at all to reduce overhead. Fixes: 3f4ff561 ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by:
Guenter Roeck <linux@roeck-us.net> Signed-off-by:
Mark Brown <broonie@kernel.org> Signed-off-by:
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Bart Van Assche authored
commit 8f2777f5 upstream. Since fc_fcp_cleanup_cmd() can sleep this function must not be called while holding a spinlock. This patch avoids that fc_fcp_cleanup_each_cmd() triggers the following bug: BUG: scheduling while atomic: sg_reset/1512/0x00000202 1 lock held by sg_reset/1512: #0: (&(&fsp->scsi_pkt_lock)->rlock){+.-...}, at: [<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc] Preemption disabled at:[<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc] Call Trace: [<ffffffff816c612c>] dump_stack+0x4f/0x7b [<ffffffff810828bc>] __schedule_bug+0x6c/0xd0 [<ffffffff816c87aa>] __schedule+0x71a/0xa10 [<ffffffff816c8ad2>] schedule+0x32/0x80 [<ffffffffc0217eac>] fc_seq_set_resp+0xac/0x100 [libfc] [<ffffffffc0218b11>] fc_exch_done+0x41/0x60 [libfc] [<ffffffffc0225cff>] fc_fcp_cleanup_each_cmd.isra.21+0xcf/0x150 [libfc] [<ffffffffc0225f43>] fc_eh_device_reset+0x1c3/0x270 [libfc] [<ffffffff814a2cc9>] scsi_try_bus_device_reset+0x29/0x60 [<ffffffff814a3908>] scsi_ioctl_reset+0x258/0x2d0 [<ffffffff814a2650>] scsi_ioctl+0x150/0x440 [<ffffffff814b3a9d>] sd_ioctl+0xad/0x120 [<ffffffff8132f266>] blkdev_ioctl+0x1b6/0x810 [<ffffffff811da608>] block_ioctl+0x38/0x40 [<ffffffff811b4e08>] do_vfs_ioctl+0x2f8/0x530 [<ffffffff811b50c1>] SyS_ioctl+0x81/0xa0 [<ffffffff816cf8b2>] system_call_fastpath+0x16/0x7a Signed-off-by:
Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by:
Vasu Dev <vasu.dev@intel.com> Signed-off-by:
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Bart Van Assche authored
commit f6979ade upstream. Due to patch "libfc: Do not invoke the response handler after fc_exch_done()" (commit ID 7030fd62) the lport_recv() call in fc_exch_recv_req() is passed a dangling pointer. Avoid this by moving the fc_frame_free() call from fc_invoke_resp() to its callers. This patch fixes the following crash: general protection fault: 0000 [#3] PREEMPT SMP RIP: fc_lport_recv_req+0x72/0x280 [libfc] Call Trace: fc_exch_recv+0x642/0xde0 [libfc] fcoe_percpu_receive_thread+0x46a/0x5ed [fcoe] kthread+0x10a/0x120 ret_from_fork+0x42/0x70 Signed-off-by:
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Thomas Hellstrom authored
commit 3e04e2fe upstream. This addresses two issues that cause problems with viewperf maya-03 in situation with memory pressure. The first issue causes attempts to unreserve buffers if batched reservation fails due to, for example, a signal pending. While previously the ttm_eu api was resistant against this type of error, it is no longer and the lockdep code will complain about attempting to unreserve buffers that are not reserved. The issue is resolved by avoid calling ttm_eu_backoff_reservation in the buffer reserve error path. The second issue is that the binding_mutex may be held when user-space fence objects are created and hence during memory reclaims. This may cause recursive attempts to grab the binding mutex. The issue is resolved by not holding the binding mutex across fence creation and submission. Signed-off-by:
Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by:
Sinclair Yeh <syeh@vmware.com> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Alex Deucher authored
commit e037239e upstream. Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
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Michael Walle authored
commit 5c16179b upstream. The commit de3910eb ("edac: change the mem allocation scheme to make Documentation/kobject.txt happy") changed the memory allocation for the csrows member. But ppc4xx_edac was forgotten in the patch. Fix it. Signed-off-by:
Michael Walle <michael@walle.cc> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Link: http://lkml.kernel.org/r/1437469253-8611-1-git-send-email-michael@walle.ccSigned-off-by:
Borislav Petkov <bp@suse.de> Signed-off-by:
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Richard Weinberger authored
commit c0ddc8c7 upstream. In kbuild it is allowed to define objects in files named "Makefile" and "Kbuild". Currently localmodconfig reads objects only from "Makefile"s and misses modules like nouveau. Link: http://lkml.kernel.org/r/1437948415-16290-1-git-send-email-richard@nod.atReported-and-tested-by:
Leonidas Spyropoulos <artafinde@gmail.com> Signed-off-by:
Richard Weinberger <richard@nod.at> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Joe Thornber authored
commit 7f518ad0 upstream. The device details and mapping trees were just being decremented before. Now btree_del() is called to do a deep delete. Signed-off-by:
Joe Thornber <ejt@redhat.com> Signed-off-by:
Mike Snitzer <snitzer@redhat.com> Signed-off-by:
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Peter Zijlstra authored
commit c7999c6f upstream. I ran the perf fuzzer, which triggered some WARN()s which are due to trying to stop/restart an event on the wrong CPU. Use the normal IPI pattern to ensure we run the code on the correct CPU. Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: bad7192b ("perf: Fix PERF_EVENT_IOC_PERIOD to force-reset the period") Signed-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Peter Zijlstra authored
commit fed66e2c upstream. Vince reported that the fasync signal stuff doesn't work proper for inherited events. So fix that. Installing fasync allocates memory and sets filp->f_flags |= FASYNC, which upon the demise of the file descriptor ensures the allocation is freed and state is updated. Now for perf, we can have the events stick around for a while after the original FD is dead because of references from child events. So we cannot copy the fasync pointer around. We can however consistently use the parent's fasync, as that will be updated. Reported-and-Tested-by:
Vince Weaver <vincent.weaver@maine.edu> Signed-off-by:
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Bob Liu authored
commit 7b076750 upstream. We should consider info->feature_persistent when adding indirect page to list info->indirect_pages, else the BUG_ON() in blkif_free() would be triggered. When we are using persistent grants the indirect_pages list should always be empty because blkfront has pre-allocated enough persistent pages to fill all requests on the ring. Acked-by:
Roger Pau Monné <roger.pau@citrix.com> Signed-off-by:
Bob Liu <bob.liu@oracle.com> Signed-off-by:
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by:
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Wanpeng Li authored
commit 4f32be67 upstream. After trying to drain pages from pagevec/pageset, we try to get reference count of the page again, however, the reference count of the page is not reduced if the page is still not on LRU list. Fix it by adding the put_page() to drop the page reference which is from __get_any_page(). Signed-off-by:
Wanpeng Li <wanpeng.li@hotmail.com> Acked-by:
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Manfred Spraul authored
commit 3ed1f8a9 upstream. sem_lock() did not properly pair memory barriers: !spin_is_locked() and spin_unlock_wait() are both only control barriers. The code needs an acquire barrier, otherwise the cpu might perform read operations before the lock test. As no primitive exists inside <include/spinlock.h> and since it seems noone wants another primitive, the code creates a local primitive within ipc/sem.c. With regards to -stable: The change of sem_wait_array() is a bugfix, the change to sem_lock() is a nop (just a preprocessor redefinition to improve the readability). The bugfix is necessary for all kernels that use sem_wait_array() (i.e.: starting from 3.10). Signed-off-by:
Manfred Spraul <manfred@colorfullife.com> Reported-by:
Oleg Nesterov <oleg@redhat.com> Acked-by:
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Herton R. Krzesinski authored
commit 602b8593 upstream. The current semaphore code allows a potential use after free: in exit_sem we may free the task's sem_undo_list while there is still another task looping through the same semaphore set and cleaning the sem_undo list at freeary function (the task called IPC_RMID for the same semaphore set). For example, with a test program [1] running which keeps forking a lot of processes (which then do a semop call with SEM_UNDO flag), and with the parent right after removing the semaphore set with IPC_RMID, and a kernel built with CONFIG_SLAB, CONFIG_SLAB_DEBUG and CONFIG_DEBUG_SPINLOCK, you can easily see something like the following in the kernel log: Slab corruption (Not tainted): kmalloc-64 start=ffff88003b45c1c0, len=64 000: 6b 6b 6b 6b 6b 6b 6b 6b 00 6b 6b 6b 6b 6b 6b 6b kkkkkkkk.kkkkkkk 010: ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ Prev obj: start=ffff88003b45c180, len=64 000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ 010: ff ff ff ff ff ff ff ff c0 fb 01 37 00 88 ff ff ...........7.... Next obj: start=ffff88003b45c200, len=64 000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a .....N......ZZZZ 010: ff ff ff ff ff ff ff ff 68 29 a7 3c 00 88 ff ff ........h).<.... BUG: spinlock wrong CPU on CPU#2, test/18028 general protection fault: 0000 [#1] SMP Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib] CPU: 2 PID: 18028 Comm: test Not tainted 4.2.0-rc5+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 RIP: spin_dump+0x53/0xc0 Call Trace: spin_bug+0x30/0x40 do_raw_spin_unlock+0x71/0xa0 _raw_spin_unlock+0xe/0x10 freeary+0x82/0x2a0 ? _raw_spin_lock+0xe/0x10 semctl_down.clone.0+0xce/0x160 ? __do_page_fault+0x19a/0x430 ? __audit_syscall_entry+0xa8/0x100 SyS_semctl+0x236/0x2c0 ? syscall_trace_leave+0xde/0x130 entry_SYSCALL_64_fastpath+0x12/0x71 Code: 8b 80 88 03 00 00 48 8d 88 60 05 00 00 48 c7 c7 a0 2c a4 81 31 c0 65 8b 15 eb 40 f3 7e e8 08 31 68 00 4d 85 e4 44 8b 4b 08 74 5e <45> 8b 84 24 88 03 00 00 49 8d 8c 24 60 05 00 00 8b 53 04 48 89 RIP [<ffffffff810d6053>] spin_dump+0x53/0xc0 RSP <ffff88003750fd68> ---[ end trace 783ebb76612867a0 ]--- NMI watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [test:18053] Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib] CPU: 3 PID: 18053 Comm: test Tainted: G D 4.2.0-rc5+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 RIP: native_read_tsc+0x0/0x20 Call Trace: ? delay_tsc+0x40/0x70 __delay+0xf/0x20 do_raw_spin_lock+0x96/0x140 _raw_spin_lock+0xe/0x10 sem_lock_and_putref+0x11/0x70 SYSC_semtimedop+0x7bf/0x960 ? handle_mm_fault+0xbf6/0x1880 ? dequeue_task_fair+0x79/0x4a0 ? __do_page_fault+0x19a/0x430 ? kfree_debugcheck+0x16/0x40 ? __do_page_fault+0x19a/0x430 ? __audit_syscall_entry+0xa8/0x100 ? do_audit_syscall_entry+0x66/0x70 ? syscall_trace_enter_phase1+0x139/0x160 SyS_semtimedop+0xe/0x10 SyS_semop+0x10/0x20 entry_SYSCALL_64_fastpath+0x12/0x71 Code: 47 10 83 e8 01 85 c0 89 47 10 75 08 65 48 89 3d 1f 74 ff 7e c9 c3 0f 1f 44 00 00 55 48 89 e5 e8 87 17 04 00 66 90 c9 c3 0f 1f 00 <55> 48 89 e5 0f 31 89 c1 48 89 d0 48 c1 e0 20 89 c9 48 09 c8 c9 Kernel panic - not syncing: softlockup: hung tasks I wasn't able to trigger any badness on a recent kernel without the proper config debugs enabled, however I have softlockup reports on some kernel versions, in the semaphore code, which are similar as above (the scenario is seen on some servers running IBM DB2 which uses semaphore syscalls). The patch here fixes the race against freeary, by acquiring or waiting on the sem_undo_list lock as necessary (exit_sem can race with freeary, while freeary sets un->semid to -1 and removes the same sem_undo from list_proc or when it removes the last sem_undo). After the patch I'm unable to reproduce the problem using the test case [1]. [1] Test case used below: #include <stdio.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/sem.h> #include <sys/wait.h> #include <stdlib.h> #include <time.h> #include <unistd.h> #include <errno.h> #define NSEM 1 #define NSET 5 int sid[NSET]; void thread() { struct sembuf op; int s; uid_t pid = getuid(); s = rand() % NSET; op.sem_num = pid % NSEM; op.sem_op = 1; op.sem_flg = SEM_UNDO; semop(sid[s], &op, 1); exit(EXIT_SUCCESS); } void create_set() { int i, j; pid_t p; union { int val; struct semid_ds *buf; unsigned short int *array; struct seminfo *__buf; } un; /* Create and initialize semaphore set */ for (i = 0; i < NSET; i++) { sid[i] = semget(IPC_PRIVATE , NSEM, 0644 | IPC_CREAT); if (sid[i] < 0) { perror("semget"); exit(EXIT_FAILURE); } } un.val = 0; for (i = 0; i < NSET; i++) { for (j = 0; j < NSEM; j++) { if (semctl(sid[i], j, SETVAL, un) < 0) perror("semctl"); } } /* Launch threads that operate on semaphore set */ for (i = 0; i < NSEM * NSET * NSET; i++) { p = fork(); if (p < 0) perror("fork"); if (p == 0) thread(); } /* Free semaphore set */ for (i = 0; i < NSET; i++) { if (semctl(sid[i], NSEM, IPC_RMID)) perror("IPC_RMID"); } /* Wait for forked processes to exit */ while (wait(NULL)) { if (errno == ECHILD) break; }; } int main(int argc, char **argv) { pid_t p; srand(time(NULL)); while (1) { p = fork(); if (p < 0) { perror("fork"); exit(EXIT_FAILURE); } if (p == 0) { create_set(); goto end; } /* Wait for forked processes to exit */ while (wait(NULL)) { if (errno == ECHILD) break; }; } end: return 0; } [akpm@linux-foundation.org: use normal comment layout] Signed-off-by:
Herton R. Krzesinski <herton@redhat.com> Acked-by:
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- 17 Aug, 2015 21 commits
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Greg Kroah-Hartman authored
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Michal Hocko authored
commit ecf5fc6e upstream. Nikolay has reported a hang when a memcg reclaim got stuck with the following backtrace: PID: 18308 TASK: ffff883d7c9b0a30 CPU: 1 COMMAND: "rsync" #0 __schedule at ffffffff815ab152 #1 schedule at ffffffff815ab76e #2 schedule_timeout at ffffffff815ae5e5 #3 io_schedule_timeout at ffffffff815aad6a #4 bit_wait_io at ffffffff815abfc6 #5 __wait_on_bit at ffffffff815abda5 #6 wait_on_page_bit at ffffffff8111fd4f #7 shrink_page_list at ffffffff81135445 #8 shrink_inactive_list at ffffffff81135845 #9 shrink_lruvec at ffffffff81135ead #10 shrink_zone at ffffffff811360c3 #11 shrink_zones at ffffffff81136eff #12 do_try_to_free_pages at ffffffff8113712f #13 try_to_free_mem_cgroup_pages at ffffffff811372be #14 try_charge at ffffffff81189423 #15 mem_cgroup_try_charge at ffffffff8118c6f5 #16 __add_to_page_cache_locked at ffffffff8112137d #17 add_to_page_cache_lru at ffffffff81121618 #18 pagecache_get_page at ffffffff8112170b #19 grow_dev_page at ffffffff811c8297 #20 __getblk_slow at ffffffff811c91d6 #21 __getblk_gfp at ffffffff811c92c1 #22 ext4_ext_grow_indepth at ffffffff8124565c #23 ext4_ext_create_new_leaf at ffffffff81246ca8 #24 ext4_ext_insert_extent at ffffffff81246f09 #25 ext4_ext_map_blocks at ffffffff8124a848 #26 ext4_map_blocks at ffffffff8121a5b7 #27 mpage_map_one_extent at ffffffff8121b1fa #28 mpage_map_and_submit_extent at ffffffff8121f07b #29 ext4_writepages at ffffffff8121f6d5 #30 do_writepages at ffffffff8112c490 #31 __filemap_fdatawrite_range at ffffffff81120199 #32 filemap_flush at ffffffff8112041c #33 ext4_alloc_da_blocks at ffffffff81219da1 #34 ext4_rename at ffffffff81229b91 #35 ext4_rename2 at ffffffff81229e32 #36 vfs_rename at ffffffff811a08a5 #37 SYSC_renameat2 at ffffffff811a3ffc #38 sys_renameat2 at ffffffff811a408e #39 sys_rename at ffffffff8119e51e #40 system_call_fastpath at ffffffff815afa89 Dave Chinner has properly pointed out that this is a deadlock in the reclaim code because ext4 doesn't submit pages which are marked by PG_writeback right away. The heuristic was introduced by commit e62e384e ("memcg: prevent OOM with too many dirty pages") and it was applied only when may_enter_fs was specified. The code has been changed by c3b94f44 ("memcg: further prevent OOM with too many dirty pages") which has removed the __GFP_FS restriction with a reasoning that we do not get into the fs code. But this is not sufficient apparently because the fs doesn't necessarily submit pages marked PG_writeback for IO right away. ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily submit the bio. Instead it tries to map more pages into the bio and mpage_map_one_extent might trigger memcg charge which might end up waiting on a page which is marked PG_writeback but hasn't been submitted yet so we would end up waiting for something that never finishes. Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2) before we go to wait on the writeback. The page fault path, which is the only path that triggers memcg oom killer since 3.12, shouldn't require GFP_NOFS and so we shouldn't reintroduce the premature OOM killer issue which was originally addressed by the heuristic. As per David Chinner the xfs is doing similar thing since 2.6.15 already so ext4 is not the only affected filesystem. Moreover he notes: : For example: IO completion might require unwritten extent conversion : which executes filesystem transactions and GFP_NOFS allocations. The : writeback flag on the pages can not be cleared until unwritten : extent conversion completes. Hence memory reclaim cannot wait on : page writeback to complete in GFP_NOFS context because it is not : safe to do so, memcg reclaim or otherwise. [tytso@mit.edu: corrected the control flow] Fixes: c3b94f44 ("memcg: further prevent OOM with too many dirty pages") Reported-by:
Nikolay Borisov <kernel@kyup.com> Signed-off-by:
Michal Hocko <mhocko@suse.cz> Signed-off-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
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NeilBrown authored
commit b97e9257 upstream Use separate bitmaps for each nodes in the cluster bitmap_read_sb() validates the bitmap superblock that it reads in. If it finds an inconsistency like a bad magic number or out-of-range version number, it prints an error and returns, but it incorrectly returns zero, so the array is still assembled with the (invalid) bitmap. This means it could try to use a bitmap with a new version number which it therefore does not understand. This bug was introduced in 3.5 and fix as part of a larger patch in 4.1. So the patch is suitable for any -stable kernel in that range. Fixes: 27581e5a ("md/bitmap: centralise allocation of bitmap file pages.") Signed-off-by:
NeilBrown <neilb@suse.com> Reported-by:
GuoQing Jiang <gqjiang@suse.com>
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Al Viro authored
commit f15133df upstream. path_openat() jumps to the wrong place after do_tmpfile() - it has already done path_cleanup() (as part of path_lookupat() called by do_tmpfile()), so doing that again can lead to double fput(). Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Paolo Bonzini authored
commit ce40cd3f upstream. Malicious (or egregiously buggy) userspace can trigger it, but it should never happen in normal operation. Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
Wang Kai <morgan.wang@huawei.com> Signed-off-by:
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Miklos Szeredi authored
commit 60942f2f upstream. Since now the shrink list is private and nobody can free the dentry while it is on the shrink list, we can remove RCU protection from this. Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> Signed-off-by:
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Al Viro authored
commit 9c8c10e2 upstream. Start with shrink_dcache_parent(), then scan what remains. First of all, BUG() is very much an overkill here; we are holding ->s_umount, and hitting BUG() means that a lot of interesting stuff will be hanging after that point (sync(2), for example). Moreover, in cases when there had been more than one leak, we'll be better off reporting all of them. And more than just the last component of pathname - %pd is there for just such uses... That was the last user of dentry_lru_del(), so kill it off... Signed-off-by:
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Al Viro authored
commit fe91522a upstream. If we find something already on a shrink list, just increment data->found and do nothing else. Loops in shrink_dcache_parent() and check_submounts_and_drop() will do the right thing - everything we did put into our list will be evicted and if there had been nothing, but data->found got non-zero, well, we have somebody else shrinking those guys; just try again. Signed-off-by:
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Al Viro authored
commit 41edf278 upstream. If the victim in on the shrink list, don't remove it from there. If shrink_dentry_list() manages to remove it from the list before we are done - fine, we'll just free it as usual. If not - mark it with new flag (DCACHE_MAY_FREE) and leave it there. Eventually, shrink_dentry_list() will get to it, remove the sucker from shrink list and call dentry_kill(dentry, 0). Which is where we'll deal with freeing. Since now dentry_kill(dentry, 0) may happen after or during dentry_kill(dentry, 1), we need to recognize that (by seeing DCACHE_DENTRY_KILLED already set), unlock everything and either free the sucker (in case DCACHE_MAY_FREE has been set) or leave it for ongoing dentry_kill(dentry, 1) to deal with. Signed-off-by:
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Al Viro authored
commit 01b60351 upstream. Signed-off-by:
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Al Viro authored
commit b4f0354e upstream. The part of old d_free() that dealt with actual freeing of dentry. Taken out of dentry_kill() into a separate function. Signed-off-by:
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Al Viro authored
commit 5c47e6d0 upstream. Signed-off-by:
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Al Viro authored
commit 03b3b889 upstream. Signed-off-by:
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Amanieu d'Antras authored
commit 3c00cb5e upstream. This function can leak kernel stack data when the user siginfo_t has a positive si_code value. The top 16 bits of si_code descibe which fields in the siginfo_t union are active, but they are treated inconsistently between copy_siginfo_from_user32, copy_siginfo_to_user32 and copy_siginfo_to_user. copy_siginfo_from_user32 is called from rt_sigqueueinfo and rt_tgsigqueueinfo in which the user has full control overthe top 16 bits of si_code. This fixes the following information leaks: x86: 8 bytes leaked when sending a signal from a 32-bit process to itself. This leak grows to 16 bytes if the process uses x32. (si_code = __SI_CHLD) x86: 100 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = -1) sparc: 4 bytes leaked when sending a signal from a 32-bit process to a 64-bit process. (si_code = any) parsic and s390 have similar bugs, but they are not vulnerable because rt_[tg]sigqueueinfo have checks that prevent sending a positive si_code to a different process. These bugs are also fixed for consistency. Signed-off-by:
Amanieu d'Antras <amanieu@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Amanieu d'Antras authored
commit 26135022 upstream. This function may copy the si_addr_lsb, si_lower and si_upper fields to user mode when they haven't been initialized, which can leak kernel stack data to user mode. Just checking the value of si_code is insufficient because the same si_code value is shared between multiple signals. This is solved by checking the value of si_signo in addition to si_code. Signed-off-by:
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Amanieu d'Antras authored
commit 3ead7c52 upstream. This function may copy the si_addr_lsb field to user mode when it hasn't been initialized, which can leak kernel stack data to user mode. Just checking the value of si_code is insufficient because the same si_code value is shared between multiple signals. This is solved by checking the value of si_signo in addition to si_code. Signed-off-by:
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Al Viro authored
commit 451a2886 upstream. unfortunately, allowing an arbitrary 16bit value means a possibility of overflow in the calculation of total number of pages in bio_map_user_iov() - we rely on there being no more than PAGE_SIZE members of sum in the first loop there. If that sum wraps around, we end up allocating too small array of pointers to pages and it's easy to overflow it in the second loop. X-Coverup: TINC (and there's no lumber cartel either) Signed-off-by:
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NeilBrown authored
commit 423f04d6 upstream. raid1_end_read_request() assumes that the In_sync bits are consistent with the ->degaded count. raid1_spare_active updates the In_sync bit before the ->degraded count and so exposes an inconsistency, as does error() So extend the spinlock in raid1_spare_active() and error() to hide those inconsistencies. This should probably be part of Commit: 34cab6f4 ("md/raid1: fix test for 'was read error from last working device'.") as it addresses the same issue. It fixes the same bug and should go to -stable for same reasons. Fixes: 76073054 ("md/raid1: clean up read_balance.") Signed-off-by:
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Michael S. Tsirkin authored
commit c9ddbac9 upstream. 09a2c73d ("PCI: Remove unused PCI_MSIX_FLAGS_BIRMASK definition") removed PCI_MSIX_FLAGS_BIRMASK from an exported header because it was unused in the kernel. But that breaks user programs that were using it (QEMU in particular). Restore the PCI_MSIX_FLAGS_BIRMASK definition. [bhelgaas: changelog] Signed-off-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> Signed-off-by:
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Joseph Qi authored
commit 209f7512 upstream. The "BUG_ON(list_empty(&osb->blocked_lock_list))" in ocfs2_downconvert_thread_do_work can be triggered in the following case: ocfs2dc has firstly saved osb->blocked_lock_count to local varibale processed, and then processes the dentry lockres. During the dentry put, it calls iput and then deletes rw, inode and open lockres from blocked list in ocfs2_mark_lockres_freeing. And this causes the variable `processed' to not reflect the number of blocked lockres to be processed, which triggers the BUG. Signed-off-by:
Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by:
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Marcus Gelderie authored
commit de54b9ac upstream. A while back, the message queue implementation in the kernel was improved to use btrees to speed up retrieval of messages, in commit d6629859 ("ipc/mqueue: improve performance of send/recv"). That patch introducing the improved kernel handling of message queues (using btrees) has, as a by-product, changed the meaning of the QSIZE field in the pseudo-file created for the queue. Before, this field reflected the size of the user-data in the queue. Since, it also takes kernel data structures into account. For example, if 13 bytes of user data are in the queue, on my machine the file reports a size of 61 bytes. There was some discussion on this topic before (for example https://lkml.org/lkml/2014/10/1/115). Commenting on a th lkml, Michael Kerrisk gave the following background (https://lkml.org/lkml/2015/6/16/74): The pseudofiles in the mqueue filesystem (usually mounted at /dev/mqueue) expose fields with metadata describing a message queue. One of these fields, QSIZE, as originally implemented, showed the total number of bytes of user data in all messages in the message queue, and this feature was documented from the beginning in the mq_overview(7) page. In 3.5, some other (useful) work happened to break the user-space API in a couple of places, including the value exposed via QSIZE, which now includes a measure of kernel overhead bytes for the queue, a figure that renders QSIZE useless for its original purpose, since there's no way to deduce the number of overhead bytes consumed by the implementation. (The other user-space breakage was subsequently fixed.) This patch removes the accounting of kernel data structures in the queue. Reporting the size of these data-structures in the QSIZE field was a breaking change (see Michael's comment above). Without the QSIZE field reporting the total size of user-data in the queue, there is no way to deduce this number. It should be noted that the resource limit RLIMIT_MSGQUEUE is counted against the worst-case size of the queue (in both the old and the new implementation). Therefore, the kernel overhead accounting in QSIZE is not necessary to help the user understand the limitations RLIMIT imposes on the processes. Signed-off-by:
Marcus Gelderie <redmnic@gmail.com> Acked-by:
Doug Ledford <dledford@redhat.com> Acked-by:
Michael Kerrisk <mtk.manpages@gmail.com> Acked-by:
Davidlohr Bueso <dbueso@suse.de> Cc: David Howells <dhowells@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: John Duffy <jb_duffy@btinternet.com> Cc: Arto Bendiken <arto@bendiken.net> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by:
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