- 22 May, 2019 40 commits
-
-
Liang Chen authored
commit a4b732a2 upstream. There is a race between cache device register and cache set unregister. For an already registered cache device, register_bcache will call bch_is_open to iterate through all cachesets and check every cache there. The race occurs if cache_set_free executes at the same time and clears the caches right before ca is dereferenced in bch_is_open_cache. To close the race, let's make sure the clean up work is protected by the bch_register_lock as well. This issue can be reproduced as follows, while true; do echo /dev/XXX> /sys/fs/bcache/register ; done& while true; do echo 1> /sys/block/XXX/bcache/set/unregister ; done & and results in the following oops, [ +0.000053] BUG: unable to handle kernel NULL pointer dereference at 0000000000000998 [ +0.000457] #PF error: [normal kernel read fault] [ +0.000464] PGD 800000003ca9d067 P4D 800000003ca9d067 PUD 3ca9c067 PMD 0 [ +0.000388] Oops: 0000 [#1] SMP PTI [ +0.000269] CPU: 1 PID: 3266 Comm: bash Not tainted 5.0.0+ #6 [ +0.000346] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.fc28 04/01/2014 [ +0.000472] RIP: 0010:register_bcache+0x1829/0x1990 [bcache] [ +0.000344] Code: b0 48 83 e8 50 48 81 fa e0 e1 10 c0 0f 84 a9 00 00 00 48 89 c6 48 89 ca 0f b7 ba 54 04 00 00 4c 8b 82 60 0c 00 00 85 ff 74 2f <49> 3b a8 98 09 00 00 74 4e 44 8d 47 ff 31 ff 49 c1 e0 03 eb 0d [ +0.000839] RSP: 0018:ffff92ee804cbd88 EFLAGS: 00010202 [ +0.000328] RAX: ffffffffc010e190 RBX: ffff918b5c6b5000 RCX: ffff918b7d8e0000 [ +0.000399] RDX: ffff918b7d8e0000 RSI: ffffffffc010e190 RDI: 0000000000000001 [ +0.000398] RBP: ffff918b7d318340 R08: 0000000000000000 R09: ffffffffb9bd2d7a [ +0.000385] R10: ffff918b7eb253c0 R11: ffffb95980f51200 R12: ffffffffc010e1a0 [ +0.000411] R13: fffffffffffffff2 R14: 000000000000000b R15: ffff918b7e232620 [ +0.000384] FS: 00007f955bec2740(0000) GS:ffff918b7eb00000(0000) knlGS:0000000000000000 [ +0.000420] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ +0.000801] CR2: 0000000000000998 CR3: 000000003cad6000 CR4: 00000000001406e0 [ +0.000837] Call Trace: [ +0.000682] ? _cond_resched+0x10/0x20 [ +0.000691] ? __kmalloc+0x131/0x1b0 [ +0.000710] kernfs_fop_write+0xfa/0x170 [ +0.000733] __vfs_write+0x2e/0x190 [ +0.000688] ? inode_security+0x10/0x30 [ +0.000698] ? selinux_file_permission+0xd2/0x120 [ +0.000752] ? security_file_permission+0x2b/0x100 [ +0.000753] vfs_write+0xa8/0x1a0 [ +0.000676] ksys_write+0x4d/0xb0 [ +0.000699] do_syscall_64+0x3a/0xf0 [ +0.000692] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Liang Chen <liangchen.linux@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Filipe Manana authored
commit 62d54f3a upstream. Send operates on read only trees and expects them to never change while it is using them. This is part of its initial design, and this expection is due to two different reasons: 1) When it was introduced, no operations were allowed to modifiy read-only subvolumes/snapshots (including defrag for example). 2) It keeps send from having an impact on other filesystem operations. Namely send does not need to keep locks on the trees nor needs to hold on to transaction handles and delay transaction commits. This ends up being a consequence of the former reason. However the deduplication feature was introduced later (on September 2013, while send was introduced in July 2012) and it allowed for deduplication with destination files that belong to read-only trees (subvolumes and snapshots). That means that having a send operation (either full or incremental) running in parallel with a deduplication that has the destination inode in one of the trees used by the send operation, can result in tree nodes and leaves getting freed and reused while send is using them. This problem is similar to the problem solved for the root nodes getting freed and reused when a snapshot is made against one tree that is currenly being used by a send operation, fixed in commits [1] and [2]. These commits explain in detail how the problem happens and the explanation is valid for any node or leaf that is not the root of a tree as well. This problem was also discussed and explained recently in a thread [3]. The problem is very easy to reproduce when using send with large trees (snapshots) and just a few concurrent deduplication operations that target files in the trees used by send. A stress test case is being sent for fstests that triggers the issue easily. The most common error to hit is the send ioctl return -EIO with the following messages in dmesg/syslog: [1631617.204075] BTRFS error (device sdc): did not find backref in send_root. inode=63292, offset=0, disk_byte=5228134400 found extent=5228134400 [1631633.251754] BTRFS error (device sdc): parent transid verify failed on 32243712 wanted 24 found 27 The first one is very easy to hit while the second one happens much less frequently, except for very large trees (in that test case, snapshots with 100000 files having large xattrs to get deep and wide trees). Less frequently, at least one BUG_ON can be hit: [1631742.130080] ------------[ cut here ]------------ [1631742.130625] kernel BUG at fs/btrfs/ctree.c:1806! [1631742.131188] invalid opcode: 0000 [#6] SMP DEBUG_PAGEALLOC PTI [1631742.131726] CPU: 1 PID: 13394 Comm: btrfs Tainted: G B D W 5.0.0-rc8-btrfs-next-45 #1 [1631742.132265] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [1631742.133399] RIP: 0010:read_node_slot+0x122/0x130 [btrfs] (...) [1631742.135061] RSP: 0018:ffffb530021ebaa0 EFLAGS: 00010246 [1631742.135615] RAX: ffff93ac8912e000 RBX: 000000000000009d RCX: 0000000000000002 [1631742.136173] RDX: 000000000000009d RSI: ffff93ac564b0d08 RDI: ffff93ad5b48c000 [1631742.136759] RBP: ffffb530021ebb7d R08: 0000000000000001 R09: ffffb530021ebb7d [1631742.137324] R10: ffffb530021eba70 R11: 0000000000000000 R12: ffff93ac87d0a708 [1631742.137900] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001 [1631742.138455] FS: 00007f4cdb1528c0(0000) GS:ffff93ad76a80000(0000) knlGS:0000000000000000 [1631742.139010] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1631742.139568] CR2: 00007f5acb3d0420 CR3: 000000012be3e006 CR4: 00000000003606e0 [1631742.140131] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1631742.140719] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1631742.141272] Call Trace: [1631742.141826] ? do_raw_spin_unlock+0x49/0xc0 [1631742.142390] tree_advance+0x173/0x1d0 [btrfs] [1631742.142948] btrfs_compare_trees+0x268/0x690 [btrfs] [1631742.143533] ? process_extent+0x1070/0x1070 [btrfs] [1631742.144088] btrfs_ioctl_send+0x1037/0x1270 [btrfs] [1631742.144645] _btrfs_ioctl_send+0x80/0x110 [btrfs] [1631742.145161] ? trace_sched_stick_numa+0xe0/0xe0 [1631742.145685] btrfs_ioctl+0x13fe/0x3120 [btrfs] [1631742.146179] ? account_entity_enqueue+0xd3/0x100 [1631742.146662] ? reweight_entity+0x154/0x1a0 [1631742.147135] ? update_curr+0x20/0x2a0 [1631742.147593] ? check_preempt_wakeup+0x103/0x250 [1631742.148053] ? do_vfs_ioctl+0xa2/0x6f0 [1631742.148510] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [1631742.148942] do_vfs_ioctl+0xa2/0x6f0 [1631742.149361] ? __fget+0x113/0x200 [1631742.149767] ksys_ioctl+0x70/0x80 [1631742.150159] __x64_sys_ioctl+0x16/0x20 [1631742.150543] do_syscall_64+0x60/0x1b0 [1631742.150931] entry_SYSCALL_64_after_hwframe+0x49/0xbe [1631742.151326] RIP: 0033:0x7f4cd9f5add7 (...) [1631742.152509] RSP: 002b:00007ffe91017708 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [1631742.152892] RAX: ffffffffffffffda RBX: 0000000000000105 RCX: 00007f4cd9f5add7 [1631742.153268] RDX: 00007ffe91017790 RSI: 0000000040489426 RDI: 0000000000000007 [1631742.153633] RBP: 0000000000000007 R08: 00007f4cd9e79700 R09: 00007f4cd9e79700 [1631742.153999] R10: 00007f4cd9e799d0 R11: 0000000000000202 R12: 0000000000000003 [1631742.154365] R13: 0000555dfae53020 R14: 0000000000000000 R15: 0000000000000001 (...) [1631742.156696] ---[ end trace 5dac9f96dcc3fd6b ]--- That BUG_ON happens because while send is using a node, that node is COWed by a concurrent deduplication, gets freed and gets reused as a leaf (because a transaction commit happened in between), so when it attempts to read a slot from the extent buffer, at ctree.c:read_node_slot(), the extent buffer contents were wiped out and it now matches a leaf (which can even belong to some other tree now), hitting the BUG_ON(level == 0). Fix this concurrency issue by not allowing send and deduplication to run in parallel if both operate on the same readonly trees, returning EAGAIN to user space and logging an exlicit warning in dmesg/syslog. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=be6821f82c3cc36e026f5afd10249988852b35ea [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6f2f0b394b54e2b159ef969a0b5274e9bbf82ff2 [3] https://lore.kernel.org/linux-btrfs/CAL3q7H7iqSEEyFaEtpRZw3cp613y+4k2Q8b4W7mweR3tZA05bQ@mail.gmail.com/ CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Filipe Manana authored
commit bfc61c36 upstream. When finding out which inodes have references on a particular extent, done by backref.c:iterate_extent_inodes(), from the BTRFS_IOC_LOGICAL_INO (both v1 and v2) ioctl and from scrub we use the transaction join API to grab a reference on the currently running transaction, since in order to give accurate results we need to inspect the delayed references of the currently running transaction. However, if there is currently no running transaction, the join operation will create a new transaction. This is inefficient as the transaction will eventually be committed, doing unnecessary IO and introducing a potential point of failure that will lead to a transaction abort due to -ENOSPC, as recently reported [1]. That's because the join, creates the transaction but does not reserve any space, so when attempting to update the root item of the root passed to btrfs_join_transaction(), during the transaction commit, we can end up failling with -ENOSPC. Users of a join operation are supposed to actually do some filesystem changes and reserve space by some means, which is not the case of iterate_extent_inodes(), it is a read-only operation for all contextes from which it is called. The reported [1] -ENOSPC failure stack trace is the following: heisenberg kernel: ------------[ cut here ]------------ heisenberg kernel: BTRFS: Transaction aborted (error -28) heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068 heisenberg kernel: FS: 0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000 heisenberg kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 heisenberg kernel: Call Trace: heisenberg kernel: commit_fs_roots+0x166/0x1d0 [btrfs] heisenberg kernel: ? _cond_resched+0x15/0x30 heisenberg kernel: ? btrfs_run_delayed_refs+0xac/0x180 [btrfs] heisenberg kernel: btrfs_commit_transaction+0x2bd/0x870 [btrfs] heisenberg kernel: ? start_transaction+0x9d/0x3f0 [btrfs] heisenberg kernel: transaction_kthread+0x147/0x180 [btrfs] heisenberg kernel: ? btrfs_cleanup_transaction+0x530/0x530 [btrfs] heisenberg kernel: kthread+0x112/0x130 heisenberg kernel: ? kthread_bind+0x30/0x30 heisenberg kernel: ret_from_fork+0x35/0x40 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]--- So fix that by using the attach API, which does not create a transaction when there is currently no running transaction. [1] https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Filipe Manana authored
commit 03628cdb upstream. During fiemap, for regular extents (non inline) we need to check if they are shared and if they are, set the shared bit. Checking if an extent is shared requires checking the delayed references of the currently running transaction, since some reference might have not yet hit the extent tree and be only in the in-memory delayed references. However we were using a transaction join for this, which creates a new transaction when there is no transaction currently running. That means that two more potential failures can happen: creating the transaction and committing it. Further, if no write activity is currently happening in the system, and fiemap calls keep being done, we end up creating and committing transactions that do nothing. In some extreme cases this can result in the commit of the transaction created by fiemap to fail with ENOSPC when updating the root item of a subvolume tree because a join does not reserve any space, leading to a trace like the following: heisenberg kernel: ------------[ cut here ]------------ heisenberg kernel: BTRFS: Transaction aborted (error -28) heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068 heisenberg kernel: FS: 0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000 heisenberg kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 heisenberg kernel: Call Trace: heisenberg kernel: commit_fs_roots+0x166/0x1d0 [btrfs] heisenberg kernel: ? _cond_resched+0x15/0x30 heisenberg kernel: ? btrfs_run_delayed_refs+0xac/0x180 [btrfs] heisenberg kernel: btrfs_commit_transaction+0x2bd/0x870 [btrfs] heisenberg kernel: ? start_transaction+0x9d/0x3f0 [btrfs] heisenberg kernel: transaction_kthread+0x147/0x180 [btrfs] heisenberg kernel: ? btrfs_cleanup_transaction+0x530/0x530 [btrfs] heisenberg kernel: kthread+0x112/0x130 heisenberg kernel: ? kthread_bind+0x30/0x30 heisenberg kernel: ret_from_fork+0x35/0x40 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]--- Since fiemap (and btrfs_check_shared()) is a read-only operation, do not do a transaction join to avoid the overhead of creating a new transaction (if there is currently no running transaction) and introducing a potential point of failure when the new transaction gets committed, instead use a transaction attach to grab a handle for the currently running transaction if any. Reported-by: Christoph Anton Mitterer <calestyo@scientia.net> Link: https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/ Fixes: afce772e ("btrfs: fix check_shared for fiemap ioctl") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Filipe Manana authored
commit 9f89d5de upstream. When we set a subvolume to read-only mode we do not flush dellaloc for any of its inodes (except if the filesystem is mounted with -o flushoncommit), since it does not affect correctness for any subsequent operations - except for a future send operation. The send operation will not be able to see the delalloc data since the respective file extent items, inode item updates, backreferences, etc, have not hit yet the subvolume and extent trees. Effectively this means data loss, since the send stream will not contain any data from existing delalloc. Another problem from this is that if the writeback starts and finishes while the send operation is in progress, we have the subvolume tree being being modified concurrently which can result in send failing unexpectedly with EIO or hitting runtime errors, assertion failures or hitting BUG_ONs, etc. Simple reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ btrfs subvolume create /mnt/sv $ xfs_io -f -c "pwrite -S 0xea 0 108K" /mnt/sv/foo $ btrfs property set /mnt/sv ro true $ btrfs send -f /tmp/send.stream /mnt/sv $ od -t x1 -A d /mnt/sv/foo 0000000 ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea * 0110592 $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ btrfs receive -f /tmp/send.stream /mnt $ echo $? 0 $ od -t x1 -A d /mnt/sv/foo 0000000 # ---> empty file Since this a problem that affects send only, fix it in send by flushing dellaloc for all the roots used by the send operation before send starts to process the commit roots. This is a problem that affects send since it was introduced (commit 31db9f7c ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive")) but backporting it to older kernels has some dependencies: - For kernels between 3.19 and 4.20, it depends on commit 3cd24c69 ("btrfs: use tagged writepage to mitigate livelock of snapshot") because the function btrfs_start_delalloc_snapshot() does not exist before that commit. So one has to either pick that commit or replace the calls to btrfs_start_delalloc_snapshot() in this patch with calls to btrfs_start_delalloc_inodes(). - For kernels older than 3.19 it also requires commit e5fa8f86 ("Btrfs: ensure send always works on roots without orphans") because it depends on the function ensure_commit_roots_uptodate() which that commits introduced. - No dependencies for 5.0+ kernels. A test case for fstests follows soon. CC: stable@vger.kernel.org # 3.19+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Nikolay Borisov authored
commit c2d1b3aa upstream. Up until now trimming the freespace was done irrespective of what the arguments of the FITRIM ioctl were. For example fstrim's -o/-l arguments will be entirely ignored. Fix it by correctly handling those paramter. This requires breaking if the found freespace extent is after the end of the passed range as well as completing trim after trimming fstrim_range::len bytes. Fixes: 499f377f ("btrfs: iterate over unused chunk space in FITRIM") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Nikolay Borisov authored
commit 537f38f0 upstream. If a an eb fails to be read for whatever reason - it's corrupted on disk and parent transid/key validations fail or IO for eb pages fail then this buffer must be removed from the buffer cache. Currently the code calls free_extent_buffer if an error occurs. Unfortunately this doesn't achieve the desired behavior since btrfs_find_create_tree_block returns with eb->refs == 2. On the other hand free_extent_buffer will only decrement the refs once leaving it added to the buffer cache radix tree. This enables later code to look up the buffer from the cache and utilize it potentially leading to a crash. The correct way to free the buffer is call free_extent_buffer_stale. This function will correctly call atomic_dec explicitly for the buffer and subsequently call release_extent_buffer which will decrement the final reference thus correctly remove the invalid buffer from buffer cache. This change affects only newly allocated buffers since they have eb->refs == 2. Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755Reported-by: Jungyeon <jungyeon@gatech.edu> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Qu Wenruo authored
commit 448de471 upstream. [BUG] When reading a file from a fuzzed image, kernel can panic like: BTRFS warning (device loop0): csum failed root 5 ino 270 off 0 csum 0x98f94189 expected csum 0x00000000 mirror 1 assertion failed: !memcmp_extent_buffer(b, &disk_key, offsetof(struct btrfs_leaf, items[0].key), sizeof(disk_key)), file: fs/btrfs/ctree.c, line: 2544 ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.h:3500! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:btrfs_search_slot.cold.24+0x61/0x63 [btrfs] Call Trace: btrfs_lookup_csum+0x52/0x150 [btrfs] __btrfs_lookup_bio_sums+0x209/0x640 [btrfs] btrfs_submit_bio_hook+0x103/0x170 [btrfs] submit_one_bio+0x59/0x80 [btrfs] extent_read_full_page+0x58/0x80 [btrfs] generic_file_read_iter+0x2f6/0x9d0 __vfs_read+0x14d/0x1a0 vfs_read+0x8d/0x140 ksys_read+0x52/0xc0 do_syscall_64+0x60/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe [CAUSE] The fuzzed image has a corrupted leaf whose first key doesn't match its parent: checksum tree key (CSUM_TREE ROOT_ITEM 0) node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c ... key (EXTENT_CSUM EXTENT_CSUM 79691776) block 29761536 gen 19 leaf 29761536 items 1 free space 1726 generation 19 owner CSUM_TREE leaf 29761536 flags 0x1(WRITTEN) backref revision 1 fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c item 0 key (EXTENT_CSUM EXTENT_CSUM 8798638964736) itemoff 1751 itemsize 2244 range start 8798638964736 end 8798641262592 length 2297856 When reading the above tree block, we have extent_buffer->refs = 2 in the context: - initial one from __alloc_extent_buffer() alloc_extent_buffer() |- __alloc_extent_buffer() |- atomic_set(&eb->refs, 1) - one being added to fs_info->buffer_radix alloc_extent_buffer() |- check_buffer_tree_ref() |- atomic_inc(&eb->refs) So if even we call free_extent_buffer() in read_tree_block or other similar situation, we only decrease the refs by 1, it doesn't reach 0 and won't be freed right now. The staled eb and its corrupted content will still be kept cached. Furthermore, we have several extra cases where we either don't do first key check or the check is not proper for all callers: - scrub We just don't have first key in this context. - shared tree block One tree block can be shared by several snapshot/subvolume trees. In that case, the first key check for one subvolume doesn't apply to another. So for the above reasons, a corrupted extent buffer can sneak into the buffer cache. [FIX] Call verify_level_key in read_block_for_search to do another verification. For that purpose the function is exported. Due to above reasons, although we can free corrupted extent buffer from cache, we still need the check in read_block_for_search(), for scrub and shared tree blocks. Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202757 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202759 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202761 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202767 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202769Reported-by: Yoon Jungyeon <jungyeon@gatech.edu> CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Debabrata Banerjee authored
commit 50b29d8f upstream. Instead of removing EXT4_MOUNT_JOURNAL_CHECKSUM from s_def_mount_opt as I assume was intended, all other options were blown away leading to _ext4_show_options() output being incorrect. Fixes: 1e381f60 ("ext4: do not allow journal_opts for fs w/o journal") Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Kirill Tkhai authored
commit 310a997f upstream. It is never possible, that number of block groups decreases, since only online grow is supported. But after a growing occured, we have to zero inode tables for just created new block groups. Fixes: 19c5246d ("ext4: add new online resize interface") Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Barret Rhoden authored
commit 7bc04c5c upstream. When remounting with debug_want_extra_isize, we were not performing the same checks that we do during a normal mount. That allowed us to set a value for s_want_extra_isize that reached outside the s_inode_size. Fixes: e2b911c5 ("ext4: clean up feature test macros with predicate functions") Reported-by: syzbot+f584efa0ac7213c226b7@syzkaller.appspotmail.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Barret Rhoden <brho@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Pan Bian authored
commit 8c380ab4 upstream. The reference to iloc.bh has been dropped in ext4_mark_iloc_dirty. However, the reference is dropped again if error occurs during ext4_handle_dirty_metadata, which may result in use-after-free bugs. Fixes: fb265c9c("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases") Signed-off-by: Pan Bian <bianpan2016@163.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Theodore Ts'o authored
commit e5d01196 upstream. In other places in fs/ext4/xattr.c, if e_value_inum is non-zero, the code ignores the value in e_value_offs. The e_value_offs *should* be zero, but we shouldn't depend upon it, since it might not be true in a corrupted/fuzzed file system. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202897 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202877Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Jan Kara authored
commit 31562b95 upstream. The sanity check in mb_find_extent() only checked that returned extent does not extend past blocksize * 8, however it should not extend past EXT4_CLUSTERS_PER_GROUP(sb). This can happen when clusters_per_group < blocksize * 8 and the tail of the bitmap is not properly filled by 1s which happened e.g. when ancient kernels have grown the filesystem. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Jiufei Xue authored
commit 742b06b5 upstream. We hit a BUG at fs/buffer.c:3057 if we detached the nbd device before unmounting ext4 filesystem. The typical chain of events leading to the BUG: jbd2_write_superblock submit_bh submit_bh_wbc BUG_ON(!buffer_mapped(bh)); The block device is removed and all the pages are invalidated. JBD2 was trying to write journal superblock to the block device which is no longer present. Fix this by checking the journal superblock's buffer head prior to submitting. Reported-by: Eric Ren <renzhen@linux.alibaba.com> Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Sergei Trofimovich authored
commit 46ca3f73 upstream. The bug manifests as an attempt to access deallocated memory: BUG: unable to handle kernel paging request at ffff9c8735448000 #PF error: [PROT] [WRITE] PGD 288a05067 P4D 288a05067 PUD 288a07067 PMD 7f60c2063 PTE 80000007f5448161 Oops: 0003 [#1] PREEMPT SMP CPU: 6 PID: 388 Comm: loadkeys Tainted: G C 5.0.0-rc6-00153-g5ded5871 #91 Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M-D3H, BIOS F12 11/14/2013 RIP: 0010:__memmove+0x81/0x1a0 Code: 4c 89 4f 10 4c 89 47 18 48 8d 7f 20 73 d4 48 83 c2 20 e9 a2 00 00 00 66 90 48 89 d1 4c 8b 5c 16 f8 4c 8d 54 17 f8 48 c1 e9 03 <f3> 48 a5 4d 89 1a e9 0c 01 00 00 0f 1f 40 00 48 89 d1 4c 8b 1e 49 RSP: 0018:ffffa1b9002d7d08 EFLAGS: 00010203 RAX: ffff9c873541af43 RBX: ffff9c873541af43 RCX: 00000c6f105cd6bf RDX: 0000637882e986b6 RSI: ffff9c8735447ffb RDI: ffff9c8735447ffb RBP: ffff9c8739cd3800 R08: ffff9c873b802f00 R09: 00000000fffff73b R10: ffffffffb82b35f1 R11: 00505b1b004d5b1b R12: 0000000000000000 R13: ffff9c873541af3d R14: 000000000000000b R15: 000000000000000c FS: 00007f450c390580(0000) GS:ffff9c873f180000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff9c8735448000 CR3: 00000007e213c002 CR4: 00000000000606e0 Call Trace: vt_do_kdgkb_ioctl+0x34d/0x440 vt_ioctl+0xba3/0x1190 ? __bpf_prog_run32+0x39/0x60 ? mem_cgroup_commit_charge+0x7b/0x4e0 tty_ioctl+0x23f/0x920 ? preempt_count_sub+0x98/0xe0 ? __seccomp_filter+0x67/0x600 do_vfs_ioctl+0xa2/0x6a0 ? syscall_trace_enter+0x192/0x2d0 ksys_ioctl+0x3a/0x70 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x54/0xe0 entry_SYSCALL_64_after_hwframe+0x49/0xbe The bug manifests on systemd systems with multiple vtcon devices: # cat /sys/devices/virtual/vtconsole/vtcon0/name (S) dummy device # cat /sys/devices/virtual/vtconsole/vtcon1/name (M) frame buffer device There systemd runs 'loadkeys' tool in tapallel for each vtcon instance. This causes two parallel ioctl(KDSKBSENT) calls to race into adding the same entry into 'func_table' array at: drivers/tty/vt/keyboard.c:vt_do_kdgkb_ioctl() The function has no locking around writes to 'func_table'. The simplest reproducer is to have initrams with the following init on a 8-CPU machine x86_64: #!/bin/sh loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & loadkeys -q windowkeys ru4 & wait The change adds lock on write path only. Reads are still racy. CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org> CC: Jiri Slaby <jslaby@suse.com> Link: https://lkml.org/lkml/2019/2/17/256Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Yifeng Li authored
commit 75ddbc1f upstream. Previously, in the userspace, it was possible to use the "setterm" command from util-linux to blank the VT console by default, using the following command. According to the man page, > The force option keeps the screen blank even if a key is pressed. It was implemented by calling TIOCL_BLANKSCREEN. case BLANKSCREEN: ioctlarg = TIOCL_BLANKSCREEN; if (ioctl(STDIN_FILENO, TIOCLINUX, &ioctlarg)) warn(_("cannot force blank")); break; However, after Linux 4.12, this command ceased to work anymore, which is unexpected. By inspecting the kernel source, it shows that the issue was triggered by the side-effect from commit a4199f5e ("tty: Disable default console blanking interval"). The console blanking is implemented by function do_blank_screen() in vt.c: "blank_state" will be initialized to "blank_normal_wait" in con_init() if AND ONLY IF ("blankinterval" > 0). If "blankinterval" is 0, "blank_state" will be "blank_off" (== 0), and a call to do_blank_screen() will always abort, even if a forced blanking is required from the user by calling TIOCL_BLANKSCREEN, the console won't be blanked. This behavior is unexpected from a user's point-of-view, since it's not mentioned in any documentation. The setterm man page suggests it will always work, and the kernel comments in uapi/linux/tiocl.h says > /* keep screen blank even if a key is pressed */ > #define TIOCL_BLANKSCREEN 14 To fix it, we simply remove the "blank_state != blank_off" check, as pointed out by Nicolas Pitre, this check doesn't logically make sense and it's safe to remove. Suggested-by: Nicolas Pitre <nicolas.pitre@linaro.org> Fixes: a4199f5e ("tty: Disable default console blanking interval") Signed-off-by: Yifeng Li <tomli@tomli.me> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Chris Packham authored
commit d4197009 upstream. When the physmap_of_core.c code was merged into physmap-core.c the ability to use MTD_PHYSMAP_OF with only MTD_RAM selected was lost. Restore this by adding MTD_RAM to the dependencies of MTD_PHYSMAP. Fixes: commit 642b1e8d ("mtd: maps: Merge physmap_of.c into physmap-core.c") Cc: <stable@vger.kernel.org> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Chris Packham authored
commit 64d14c6f upstream. When the gpio-addr-flash.c driver was merged with physmap-core.c the code to store the current gpio_values was lost. This meant that once a gpio was asserted it was never de-asserted. Fix this by storing the current offset in gpio_values like the old driver used to. Fixes: commit ba32ce95 ("mtd: maps: Merge gpio-addr-flash.c into physmap-core.c") Cc: <stable@vger.kernel.org> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Alexander Sverdlin authored
commit 2b75ebee upstream. It was observed that reads crossing 4K address boundary are failing. This limitation is mentioned in Intel documents: Intel(R) 9 Series Chipset Family Platform Controller Hub (PCH) Datasheet: "5.26.3 Flash Access Program Register Access: * Program Register Accesses are not allowed to cross a 4 KB boundary..." Enhanced Serial Peripheral Interface (eSPI) Interface Base Specification (for Client and Server Platforms): "5.1.4 Address For other memory transactions, the address may start or end at any byte boundary. However, the address and payload length combination must not cross the naturally aligned address boundary of the corresponding Maximum Payload Size. It must not cross a 4 KB address boundary." Avoid this by splitting an operation crossing the boundary into two operations. Fixes: 8afda8b2 ("spi-nor: Add support for Intel SPI serial flash controller") Cc: stable@vger.kernel.org Reported-by: Romain Porte <romain.porte@nokia.com> Tested-by: Pascal Fabreges <pascal.fabreges@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Dmitry Osipenko authored
commit ea611d1c upstream. The FPS_PERIOD_MAX_US definitions are swapped for MAX20024 and MAX77620, fix it. Cc: stable <stable@vger.kernel.org> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Steve Twiss authored
commit 6b4814a9 upstream. Mismatch between what is found in the Datasheets for DA9063 and DA9063L provided by Dialog Semiconductor, and the register names provided in the MFD registers file. The changes are for the OTP (one-time-programming) control registers. The two naming errors are OPT instead of OTP, and COUNT instead of CONT (i.e. control). Cc: Stable <stable@vger.kernel.org> Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Erik Schmauss authored
commit 11207b4d upstream. ACPICA commit c14f17fa0acf8c93497ce04b9a7f4ada51b69383 This flag should not be included in #ifndef CONFIG_ACPI. It should be used unconditionally. Link: https://github.com/acpica/acpica/commit/c14f17fa Fixes: aa9aaa4d ("ACPI: use different default debug value than ACPICA") Reported-by: Gabriel C <nix.or.die@gmail.com> Tested-by: Gabriel C <nix.or.die@gmail.com> Signed-off-by: Erik Schmauss <erik.schmauss@intel.com> Signed-off-by: Bob Moore <robert.moore@intel.com> Cc: 5.1+ <stable@vger.kernel.org> 5.1+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Rajat Jain authored
commit 2f844b61 upstream. I noticed that recently multiple systems (chromebooks) couldn't wake from S0ix using LID or Keyboard after updating to a newer kernel. I bisected and it turned up commit f941d3e4 ("ACPI: EC / PM: Disable non-wakeup GPEs for suspend-to-idle"). I checked that the issue got fixed if that commit was reverted. I debugged and found that although PNP0C0D:00 (representing the LID) is wake capable and should wakeup the system per the code in acpi_wakeup_gpe_init() and in drivers/acpi/button.c: localhost /sys # cat /proc/acpi/wakeup Device S-state Status Sysfs node LID0 S4 *enabled platform:PNP0C0D:00 CREC S5 *disabled platform:GOOG0004:00 *disabled platform:cros-ec-dev.1.auto *disabled platform:cros-ec-accel.0 *disabled platform:cros-ec-accel.1 *disabled platform:cros-ec-gyro.0 *disabled platform:cros-ec-ring.0 *disabled platform:cros-usbpd-charger.2.auto *disabled platform:cros-usbpd-logger.3.auto D015 S3 *enabled i2c:i2c-ELAN0000:00 PENH S3 *enabled platform:PRP0001:00 XHCI S3 *enabled pci:0000:00:14.0 GLAN S4 *disabled WIFI S3 *disabled pci:0000:00:14.3 localhost /sys # On debugging, I found that its corresponding GPE is not being enabled. The particular GPE's "gpe_register_info->enable_for_wake" does not have any bits set when acpi_enable_all_wakeup_gpes() comes around to use it. I looked at code and could not find any other code path that should set the bits in "enable_for_wake" bitmask for the wake enabled devices for s2idle. [I do see that it happens for S3 in acpi_sleep_prepare()]. Thus I used the same call to enable the GPEs for wake enabled devices, and verified that this fixes the regression I was seeing on multiple of my devices. [ rjw: The problem is that commit f941d3e4 ("ACPI: EC / PM: Disable non-wakeup GPEs for suspend-to-idle") forgot to add the acpi_enable_wakeup_devices() call for s2idle along with acpi_enable_all_wakeup_gpes(). ] Fixes: f941d3e4 ("ACPI: EC / PM: Disable non-wakeup GPEs for suspend-to-idle") Link: https://bugzilla.kernel.org/show_bug.cgi?id=203579Signed-off-by: Rajat Jain <rajatja@google.com> [ rjw: Subject & changelog ] Cc: 5.0+ <stable@vger.kernel.org> # 5.0+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Andrea Arcangeli authored
commit c3f3ce04 upstream. The task structure is freed while get_mem_cgroup_from_mm() holds rcu_read_lock() and dereferences mm->owner. get_mem_cgroup_from_mm() failing fork() ---- --- task = mm->owner mm->owner = NULL; free(task) if (task) *task; /* use after free */ The fix consists in freeing the task with RCU also in the fork failure case, exactly like it always happens for the regular exit(2) path. That is enough to make the rcu_read_lock hold in get_mem_cgroup_from_mm() (left side above) effective to avoid a use after free when dereferencing the task structure. An alternate possible fix would be to defer the delivery of the userfaultfd contexts to the monitor until after fork() is guaranteed to succeed. Such a change would require more changes because it would create a strict ordering dependency where the uffd methods would need to be called beyond the last potentially failing branch in order to be safe. This solution as opposed only adds the dependency to common code to set mm->owner to NULL and to free the task struct that was pointed by mm->owner with RCU, if fork ends up failing. The userfaultfd methods can still be called anywhere during the fork runtime and the monitor will keep discarding orphaned "mm" coming from failed forks in userland. This race condition couldn't trigger if CONFIG_MEMCG was set =n at build time. [aarcange@redhat.com: improve changelog, reduce #ifdefs per Michal] Link: http://lkml.kernel.org/r/20190429035752.4508-1-aarcange@redhat.com Link: http://lkml.kernel.org/r/20190325225636.11635-2-aarcange@redhat.com Fixes: 893e26e6 ("userfaultfd: non-cooperative: Add fork() event") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Tested-by: zhong jiang <zhongjiang@huawei.com> Reported-by: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Peter Xu <peterx@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: zhong jiang <zhongjiang@huawei.com> Cc: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Shuning Zhang authored
commit e091eab0 upstream. In some cases, ocfs2_iget() reads the data of inode, which has been deleted for some reason. That will make the system panic. So We should judge whether this inode has been deleted, and tell the caller that the inode is a bad inode. For example, the ocfs2 is used as the backed of nfs, and the client is nfsv3. This issue can be reproduced by the following steps. on the nfs server side, ..../patha/pathb Step 1: The process A was scheduled before calling the function fh_verify. Step 2: The process B is removing the 'pathb', and just completed the call to function dput. Then the dentry of 'pathb' has been deleted from the dcache, and all ancestors have been deleted also. The relationship of dentry and inode was deleted through the function hlist_del_init. The following is the call stack. dentry_iput->hlist_del_init(&dentry->d_u.d_alias) At this time, the inode is still in the dcache. Step 3: The process A call the function ocfs2_get_dentry, which get the inode from dcache. Then the refcount of inode is 1. The following is the call stack. nfsd3_proc_getacl->fh_verify->exportfs_decode_fh->fh_to_dentry(ocfs2_get_dentry) Step 4: Dirty pages are flushed by bdi threads. So the inode of 'patha' is evicted, and this directory was deleted. But the inode of 'pathb' can't be evicted, because the refcount of the inode was 1. Step 5: The process A keep running, and call the function reconnect_path(in exportfs_decode_fh), which call function ocfs2_get_parent of ocfs2. Get the block number of parent directory(patha) by the name of ... Then read the data from disk by the block number. But this inode has been deleted, so the system panic. Process A Process B 1. in nfsd3_proc_getacl | 2. | dput 3. fh_to_dentry(ocfs2_get_dentry) | 4. bdi flush dirty cache | 5. ocfs2_iget | [283465.542049] OCFS2: ERROR (device sdp): ocfs2_validate_inode_block: Invalid dinode #580640: OCFS2_VALID_FL not set [283465.545490] Kernel panic - not syncing: OCFS2: (device sdp): panic forced after error [283465.546889] CPU: 5 PID: 12416 Comm: nfsd Tainted: G W 4.1.12-124.18.6.el6uek.bug28762940v3.x86_64 #2 [283465.548382] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/21/2015 [283465.549657] 0000000000000000 ffff8800a56fb7b8 ffffffff816e839c ffffffffa0514758 [283465.550392] 000000000008dc20 ffff8800a56fb838 ffffffff816e62d3 0000000000000008 [283465.551056] ffff880000000010 ffff8800a56fb848 ffff8800a56fb7e8 ffff88005df9f000 [283465.551710] Call Trace: [283465.552516] [<ffffffff816e839c>] dump_stack+0x63/0x81 [283465.553291] [<ffffffff816e62d3>] panic+0xcb/0x21b [283465.554037] [<ffffffffa04e66b0>] ocfs2_handle_error+0xf0/0xf0 [ocfs2] [283465.554882] [<ffffffffa04e7737>] __ocfs2_error+0x67/0x70 [ocfs2] [283465.555768] [<ffffffffa049c0f9>] ocfs2_validate_inode_block+0x229/0x230 [ocfs2] [283465.556683] [<ffffffffa047bcbc>] ocfs2_read_blocks+0x46c/0x7b0 [ocfs2] [283465.557408] [<ffffffffa049bed0>] ? ocfs2_inode_cache_io_unlock+0x20/0x20 [ocfs2] [283465.557973] [<ffffffffa049f0eb>] ocfs2_read_inode_block_full+0x3b/0x60 [ocfs2] [283465.558525] [<ffffffffa049f5ba>] ocfs2_iget+0x4aa/0x880 [ocfs2] [283465.559082] [<ffffffffa049146e>] ocfs2_get_parent+0x9e/0x220 [ocfs2] [283465.559622] [<ffffffff81297c05>] reconnect_path+0xb5/0x300 [283465.560156] [<ffffffff81297f46>] exportfs_decode_fh+0xf6/0x2b0 [283465.560708] [<ffffffffa062faf0>] ? nfsd_proc_getattr+0xa0/0xa0 [nfsd] [283465.561262] [<ffffffff810a8196>] ? prepare_creds+0x26/0x110 [283465.561932] [<ffffffffa0630860>] fh_verify+0x350/0x660 [nfsd] [283465.562862] [<ffffffffa0637804>] ? nfsd_cache_lookup+0x44/0x630 [nfsd] [283465.563697] [<ffffffffa063a8b9>] nfsd3_proc_getattr+0x69/0xf0 [nfsd] [283465.564510] [<ffffffffa062cf60>] nfsd_dispatch+0xe0/0x290 [nfsd] [283465.565358] [<ffffffffa05eb892>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc] [283465.566272] [<ffffffffa05ea652>] svc_process_common+0x412/0x6a0 [sunrpc] [283465.567155] [<ffffffffa05eaa03>] svc_process+0x123/0x210 [sunrpc] [283465.568020] [<ffffffffa062c90f>] nfsd+0xff/0x170 [nfsd] [283465.568962] [<ffffffffa062c810>] ? nfsd_destroy+0x80/0x80 [nfsd] [283465.570112] [<ffffffff810a622b>] kthread+0xcb/0xf0 [283465.571099] [<ffffffff810a6160>] ? kthread_create_on_node+0x180/0x180 [283465.572114] [<ffffffff816f11b8>] ret_from_fork+0x58/0x90 [283465.573156] [<ffffffff810a6160>] ? kthread_create_on_node+0x180/0x180 Link: http://lkml.kernel.org/r/1554185919-3010-1-git-send-email-sunny.s.zhang@oracle.comSigned-off-by: Shuning Zhang <sunny.s.zhang@oracle.com> Reviewed-by: Joseph Qi <jiangqi903@gmail.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: piaojun <piaojun@huawei.com> Cc: "Gang He" <ghe@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Mike Kravetz authored
commit 1b426bac upstream. hugetlb uses a fault mutex hash table to prevent page faults of the same pages concurrently. The key for shared and private mappings is different. Shared keys off address_space and file index. Private keys off mm and virtual address. Consider a private mappings of a populated hugetlbfs file. A fault will map the page from the file and if needed do a COW to map a writable page. Hugetlbfs hole punch uses the fault mutex to prevent mappings of file pages. It uses the address_space file index key. However, private mappings will use a different key and could race with this code to map the file page. This causes problems (BUG) for the page cache remove code as it expects the page to be unmapped. A sample stack is: page dumped because: VM_BUG_ON_PAGE(page_mapped(page)) kernel BUG at mm/filemap.c:169! ... RIP: 0010:unaccount_page_cache_page+0x1b8/0x200 ... Call Trace: __delete_from_page_cache+0x39/0x220 delete_from_page_cache+0x45/0x70 remove_inode_hugepages+0x13c/0x380 ? __add_to_page_cache_locked+0x162/0x380 hugetlbfs_fallocate+0x403/0x540 ? _cond_resched+0x15/0x30 ? __inode_security_revalidate+0x5d/0x70 ? selinux_file_permission+0x100/0x130 vfs_fallocate+0x13f/0x270 ksys_fallocate+0x3c/0x80 __x64_sys_fallocate+0x1a/0x20 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 There seems to be another potential COW issue/race with this approach of different private and shared keys as noted in commit 8382d914 ("mm, hugetlb: improve page-fault scalability"). Since every hugetlb mapping (even anon and private) is actually a file mapping, just use the address_space index key for all mappings. This results in potentially more hash collisions. However, this should not be the common case. Link: http://lkml.kernel.org/r/20190328234704.27083-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20190412165235.t4sscoujczfhuiyt@linux-r8p5 Fixes: b5cec28d ("hugetlbfs: truncate_hugepages() takes a range of pages") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Kai Shen authored
commit 2bf753e6 upstream. spinlock recursion happened when do LTP test: #!/bin/bash ./runltp -p -f hugetlb & ./runltp -p -f hugetlb & ./runltp -p -f hugetlb & ./runltp -p -f hugetlb & ./runltp -p -f hugetlb & The dtor returned by get_compound_page_dtor in __put_compound_page may be the function of free_huge_page which will lock the hugetlb_lock, so don't put_page in lock of hugetlb_lock. BUG: spinlock recursion on CPU#0, hugemmap05/1079 lock: hugetlb_lock+0x0/0x18, .magic: dead4ead, .owner: hugemmap05/1079, .owner_cpu: 0 Call trace: dump_backtrace+0x0/0x198 show_stack+0x24/0x30 dump_stack+0xa4/0xcc spin_dump+0x84/0xa8 do_raw_spin_lock+0xd0/0x108 _raw_spin_lock+0x20/0x30 free_huge_page+0x9c/0x260 __put_compound_page+0x44/0x50 __put_page+0x2c/0x60 alloc_surplus_huge_page.constprop.19+0xf0/0x140 hugetlb_acct_memory+0x104/0x378 hugetlb_reserve_pages+0xe0/0x250 hugetlbfs_file_mmap+0xc0/0x140 mmap_region+0x3e8/0x5b0 do_mmap+0x280/0x460 vm_mmap_pgoff+0xf4/0x128 ksys_mmap_pgoff+0xb4/0x258 __arm64_sys_mmap+0x34/0x48 el0_svc_common+0x78/0x130 el0_svc_handler+0x38/0x78 el0_svc+0x8/0xc Link: http://lkml.kernel.org/r/b8ade452-2d6b-0372-32c2-703644032b47@huawei.com Fixes: 9980d744 ("mm, hugetlb: get rid of surplus page accounting tricks") Signed-off-by: Kai Shen <shenkai8@huawei.com> Signed-off-by: Feilong Lin <linfeilong@huawei.com> Reported-by: Wang Wang <wangwang2@huawei.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Dan Williams authored
commit fce86ff5 upstream. Starting with c6f3c5ee ("mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()") vmf_insert_pfn_pmd() internally calls pmdp_set_access_flags(). That helper enforces a pmd aligned @address argument via VM_BUG_ON() assertion. Update the implementation to take a 'struct vm_fault' argument directly and apply the address alignment fixup internally to fix crash signatures like: kernel BUG at arch/x86/mm/pgtable.c:515! invalid opcode: 0000 [#1] SMP NOPTI CPU: 51 PID: 43713 Comm: java Tainted: G OE 4.19.35 #1 [..] RIP: 0010:pmdp_set_access_flags+0x48/0x50 [..] Call Trace: vmf_insert_pfn_pmd+0x198/0x350 dax_iomap_fault+0xe82/0x1190 ext4_dax_huge_fault+0x103/0x1f0 ? __switch_to_asm+0x40/0x70 __handle_mm_fault+0x3f6/0x1370 ? __switch_to_asm+0x34/0x70 ? __switch_to_asm+0x40/0x70 handle_mm_fault+0xda/0x200 __do_page_fault+0x249/0x4f0 do_page_fault+0x32/0x110 ? page_fault+0x8/0x30 page_fault+0x1e/0x30 Link: http://lkml.kernel.org/r/155741946350.372037.11148198430068238140.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: c6f3c5ee ("mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Piotr Balcer <piotr.balcer@intel.com> Tested-by: Yan Ma <yan.ma@intel.com> Tested-by: Pankaj Gupta <pagupta@redhat.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Chandan Rajendra <chandan@linux.ibm.com> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Jiri Kosina authored
commit 134fca90 upstream. The semantics of what mincore() considers to be resident is not completely clear, but Linux has always (since 2.3.52, which is when mincore() was initially done) treated it as "page is available in page cache". That's potentially a problem, as that [in]directly exposes meta-information about pagecache / memory mapping state even about memory not strictly belonging to the process executing the syscall, opening possibilities for sidechannel attacks. Change the semantics of mincore() so that it only reveals pagecache information for non-anonymous mappings that belog to files that the calling process could (if it tried to) successfully open for writing; otherwise we'd be including shared non-exclusive mappings, which - is the sidechannel - is not the usecase for mincore(), as that's primarily used for data, not (shared) text [jkosina@suse.cz: v2] Link: http://lkml.kernel.org/r/20190312141708.6652-2-vbabka@suse.cz [mhocko@suse.com: restructure can_do_mincore() conditions] Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1903062342020.19912@cbobk.fhfr.pmSigned-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Josh Snyder <joshs@netflix.com> Acked-by: Michal Hocko <mhocko@suse.com> Originally-by: Linus Torvalds <torvalds@linux-foundation.org> Originally-by: Dominique Martinet <asmadeus@codewreck.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Chinner <david@fromorbit.com> Cc: Kevin Easton <kevin@guarana.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Cyril Hrubis <chrubis@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Daniel Gruss <daniel@gruss.cc> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Ofir Drang authored
commit 7138377c upstream. in order to support cryptocell tee fips error that may occurs while cryptocell ree is suspended, an cc_tee_handle_fips_error call added to the cc_pm_resume function. Signed-off-by: Ofir Drang <ofir.drang@arm.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Ofir Drang authored
commit 897ab231 upstream. Adds function that checks if cryptocell tee fips error occurred and in such case triggers system error through kernel panic. Change fips function to use this new routine. Signed-off-by: Ofir Drang <ofir.drang@arm.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Ofir Drang authored
commit 3499efbe upstream. During power management suspend the driver need to prepare the device for the power down operation and as a last indication write to the HOST_POWER_DOWN_EN register which signals to the hardware that The ccree is ready for power down. Signed-off-by: Ofir Drang <ofir.drang@arm.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Ofir Drang authored
commit 7766dd77 upstream. On power management resume function first enable the device clk source to allow access to the device registers. Signed-off-by: Ofir Drang <ofir.drang@arm.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Gilad Ben-Yossef authored
commit e8662a6a upstream. The AEAD authenc key and IVs might be passed to us on stack. Copy it to a slab buffer before mapping to gurantee proper DMA mapping. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Gilad Ben-Yossef authored
commit f3df82b4 upstream. We were computing the size of the import buffer based on the digest size but the 318 and 224 byte variants use 512 and 256 bytes internal state sizes respectfully, thus causing the import buffer to overrun. Fix it by using the right sizes. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Gilad Ben-Yossef authored
commit 874e1637 upstream. The MAC hash key might be passed to us on stack. Copy it to a slab buffer before mapping to gurantee proper DMA mapping. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Gilad Ben-Yossef authored
commit d574b707 upstream. Fix a memory leak on the error path of IV generation code. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Gilad Ben-Yossef authored
commit c4b22bf5 upstream. We were handling chained scattergather lists with specialized code needlessly as the regular sg APIs handle them just fine. The code handling this also had an (unused) code path with a use-before-init error, flagged by Coverity. Remove all special handling of chained sg and leave their handling to the regular sg APIs. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Daniel Borkmann authored
commit af959b18 upstream. systemtap folks reported the following splat recently: [ 7790.862212] WARNING: CPU: 3 PID: 26759 at arch/x86/kernel/kprobes/core.c:1022 kprobe_fault_handler+0xec/0xf0 [...] [ 7790.864113] CPU: 3 PID: 26759 Comm: sshd Not tainted 5.1.0-0.rc7.git1.1.fc31.x86_64 #1 [ 7790.864198] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS[...] [ 7790.864314] RIP: 0010:kprobe_fault_handler+0xec/0xf0 [ 7790.864375] Code: 48 8b 50 [...] [ 7790.864714] RSP: 0018:ffffc06800bdbb48 EFLAGS: 00010082 [ 7790.864812] RAX: ffff9e2b75a16320 RBX: 0000000000000000 RCX: 0000000000000000 [ 7790.865306] RDX: ffffffffffffffff RSI: 000000000000000e RDI: ffffc06800bdbbf8 [ 7790.865514] RBP: ffffc06800bdbbf8 R08: 0000000000000000 R09: 0000000000000000 [ 7790.865960] R10: 0000000000000000 R11: 0000000000000000 R12: ffffc06800bdbbf8 [ 7790.866037] R13: ffff9e2ab56a0418 R14: ffff9e2b6d0bb400 R15: ffff9e2b6d268000 [ 7790.866114] FS: 00007fde49937d80(0000) GS:ffff9e2b75a00000(0000) knlGS:0000000000000000 [ 7790.866193] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7790.866318] CR2: 0000000000000000 CR3: 000000012f312000 CR4: 00000000000006e0 [ 7790.866419] Call Trace: [ 7790.866677] do_user_addr_fault+0x64/0x480 [ 7790.867513] do_page_fault+0x33/0x210 [ 7790.868002] async_page_fault+0x1e/0x30 [ 7790.868071] RIP: 0010: (null) [ 7790.868144] Code: Bad RIP value. [ 7790.868229] RSP: 0018:ffffc06800bdbca8 EFLAGS: 00010282 [ 7790.868362] RAX: ffff9e2b598b60f8 RBX: ffffc06800bdbe48 RCX: 0000000000000004 [ 7790.868629] RDX: 0000000000000004 RSI: ffffc06800bdbc6c RDI: ffff9e2b598b60f0 [ 7790.868834] RBP: ffffc06800bdbcf8 R08: 0000000000000000 R09: 0000000000000004 [ 7790.870432] R10: 00000000ff6f7a03 R11: 0000000000000000 R12: 0000000000000001 [ 7790.871859] R13: ffffc06800bdbcb8 R14: 0000000000000000 R15: ffff9e2acd0a5310 [ 7790.873455] ? vfs_read+0x5/0x170 [ 7790.874639] ? vfs_read+0x1/0x170 [ 7790.875834] ? trace_call_bpf+0xf6/0x260 [ 7790.877044] ? vfs_read+0x1/0x170 [ 7790.878208] ? vfs_read+0x5/0x170 [ 7790.879345] ? kprobe_perf_func+0x233/0x260 [ 7790.880503] ? vfs_read+0x1/0x170 [ 7790.881632] ? vfs_read+0x5/0x170 [ 7790.882751] ? kprobe_ftrace_handler+0x92/0xf0 [ 7790.883926] ? __vfs_read+0x30/0x30 [ 7790.885050] ? ftrace_ops_assist_func+0x94/0x100 [ 7790.886183] ? vfs_read+0x1/0x170 [ 7790.887283] ? vfs_read+0x5/0x170 [ 7790.888348] ? ksys_read+0x5a/0xe0 [ 7790.889389] ? do_syscall_64+0x5c/0xa0 [ 7790.890401] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe After some debugging, turns out that the logic in 2cbd95a5 ("bpf: change parameters of call/branch offset adjustment") has a bug that is exposed after 52875a04 ("bpf: verifier: remove dead code") in that we miss some of the jump offset adjustments after code patching when we remove dead code, more concretely, upon backward jump spanning over the area that is being removed. BPF insns of a case that was hit pre 52875a04: [...] 676: (85) call bpf_perf_event_output#-47616 677: (05) goto pc-636 678: (62) *(u32 *)(r10 -64) = 0 679: (bf) r7 = r10 680: (07) r7 += -64 681: (05) goto pc-44 682: (05) goto pc-1 683: (05) goto pc-1 BPF insns afterwards: [...] 618: (85) call bpf_perf_event_output#-47616 619: (05) goto pc-638 620: (62) *(u32 *)(r10 -64) = 0 621: (bf) r7 = r10 622: (07) r7 += -64 623: (05) goto pc-44 To illustrate the bug, situation looks as follows: ____ 0 | | <-- foo: [...] 1 |____| 2 |____| <-- pos / end_new ^ 3 | | | 4 | | | len 5 |____| | (remove region) 6 | | <-- end_old v 7 | | 8 | | <-- curr (jmp foo) 9 |____| The condition curr >= end_new && curr + off + 1 < end_new in the branch delta adjustments is never hit because curr + off + 1 < end_new is compared as unsigned and therefore curr + off + 1 > end_new in unsigned realm as curr + off + 1 becomes negative since the insns are memmove()'d before the offset adjustments. Correct BPF insns after this fix: [...] 618: (85) call bpf_perf_event_output#-47216 619: (05) goto pc-578 620: (62) *(u32 *)(r10 -64) = 0 621: (bf) r7 = r10 622: (07) r7 += -64 623: (05) goto pc-44 Note that unprivileged case is not affected from this. Fixes: 52875a04 ("bpf: verifier: remove dead code") Fixes: 2cbd95a5 ("bpf: change parameters of call/branch offset adjustment") Reported-by: Frank Ch. Eigler <fche@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-