Hello,
syzbot found the following issue on:
HEAD commit: d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15f19ca5d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=53fdf14defd48c56
dashboard link: https://syzkaller.appspot.com/bug?extid=9d90dad32dd9727ed084
compiler: Debian clang version 11.0.1-2
Unfortunately, I don't have any reproducer for this issue yet.
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
==================================================================
BUG: KFENCE: use-after-free write in kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
kfence-#10 [0xffff88823bc16000-0xffff88823bc160df, size=224, cache=kmem_cache] allocated by task 15453:
kmem_cache_zalloc include/linux/slab.h:676 [inline]
create_cache mm/slab_common.c:247 [inline]
kmem_cache_create_usercopy+0x12a/0x2f0 mm/slab_common.c:350
kmem_cache_create+0xf/0x20 mm/slab_common.c:405
f2fs_kmem_cache_create fs/f2fs/f2fs.h:2463 [inline]
f2fs_recover_fsync_data+0x1f0/0x8380 fs/f2fs/recovery.c:790
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
freed by task 15448:
kobject_cleanup+0x1c9/0x280 lib/kobject.c:705
shutdown_cache mm/slab_common.c:463 [inline]
kmem_cache_destroy+0x93/0x120 mm/slab_common.c:492
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
CPU: 0 PID: 15453 Comm: syz-executor.0 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:488
Code: 0f 1f 84 00 00 00 00 00 0f 1f 00 48 85 ff 0f 84 09 01 00 00 41 57 41 56 53 48 89 fb 48 c7 c7 b8 07 dc 8c 31 f6 e8 b1 c3 00 08 <ff> 4b 40 0f 85 c0 00 00 00 48 89 df e8 20 a2 14 00 48 89 df e8 18
RSP: 0018:ffffc900030af320 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88823bc16000 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc900030af870 R08: dffffc0000000000 R09: fffffbfff19b80f8
R10: fffffbfff19b80f8 R11: 0000000000000000 R12: ffff88808c3a4000
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000615eb0
FS: 00007f60a5228700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88823bc16040 CR3: 000000001ccd8000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x467b1a
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f60a5227fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000467b1a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f60a5228000
RBP: 00007f60a5228040 R08: 00007f60a5228040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f60a5228000 R15: 0000000020014b00
==================================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
On Mon, May 3, 2021 at 10:24 AM syzbot
<[email protected]> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=15f19ca5d00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=53fdf14defd48c56
> dashboard link: https://syzkaller.appspot.com/bug?extid=9d90dad32dd9727ed084
> compiler: Debian clang version 11.0.1-2
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
This looks like a bug in F2FS.
Interestingly this was detected by ARM MTE before but was
mis-root-caused I think:
https://lore.kernel.org/lkml/[email protected]/
This can't be detected by KASAN directly because it doesn't instrument
mm/slab*. This can only be detected by MTE/KFENCE.
> ==================================================================
> BUG: KFENCE: use-after-free write in kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
>
> Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
> kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> mount_bdev+0x26c/0x3a0 fs/super.c:1367
> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> vfs_get_tree+0x86/0x270 fs/super.c:1497
> do_new_mount fs/namespace.c:2905 [inline]
> path_mount+0x196f/0x2be0 fs/namespace.c:3235
> do_mount fs/namespace.c:3248 [inline]
> __do_sys_mount fs/namespace.c:3456 [inline]
> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> kfence-#10 [0xffff88823bc16000-0xffff88823bc160df, size=224, cache=kmem_cache] allocated by task 15453:
> kmem_cache_zalloc include/linux/slab.h:676 [inline]
> create_cache mm/slab_common.c:247 [inline]
> kmem_cache_create_usercopy+0x12a/0x2f0 mm/slab_common.c:350
> kmem_cache_create+0xf/0x20 mm/slab_common.c:405
> f2fs_kmem_cache_create fs/f2fs/f2fs.h:2463 [inline]
> f2fs_recover_fsync_data+0x1f0/0x8380 fs/f2fs/recovery.c:790
> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> mount_bdev+0x26c/0x3a0 fs/super.c:1367
> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> vfs_get_tree+0x86/0x270 fs/super.c:1497
> do_new_mount fs/namespace.c:2905 [inline]
> path_mount+0x196f/0x2be0 fs/namespace.c:3235
> do_mount fs/namespace.c:3248 [inline]
> __do_sys_mount fs/namespace.c:3456 [inline]
> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> freed by task 15448:
> kobject_cleanup+0x1c9/0x280 lib/kobject.c:705
> shutdown_cache mm/slab_common.c:463 [inline]
> kmem_cache_destroy+0x93/0x120 mm/slab_common.c:492
> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> mount_bdev+0x26c/0x3a0 fs/super.c:1367
> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> vfs_get_tree+0x86/0x270 fs/super.c:1497
> do_new_mount fs/namespace.c:2905 [inline]
> path_mount+0x196f/0x2be0 fs/namespace.c:3235
> do_mount fs/namespace.c:3248 [inline]
> __do_sys_mount fs/namespace.c:3456 [inline]
> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> CPU: 0 PID: 15453 Comm: syz-executor.0 Not tainted 5.12.0-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:488
> Code: 0f 1f 84 00 00 00 00 00 0f 1f 00 48 85 ff 0f 84 09 01 00 00 41 57 41 56 53 48 89 fb 48 c7 c7 b8 07 dc 8c 31 f6 e8 b1 c3 00 08 <ff> 4b 40 0f 85 c0 00 00 00 48 89 df e8 20 a2 14 00 48 89 df e8 18
> RSP: 0018:ffffc900030af320 EFLAGS: 00010286
> RAX: 0000000000000000 RBX: ffff88823bc16000 RCX: 0000000000000001
> RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
> RBP: ffffc900030af870 R08: dffffc0000000000 R09: fffffbfff19b80f8
> R10: fffffbfff19b80f8 R11: 0000000000000000 R12: ffff88808c3a4000
> R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000615eb0
> FS: 00007f60a5228700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: ffff88823bc16040 CR3: 000000001ccd8000 CR4: 00000000001526f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> mount_bdev+0x26c/0x3a0 fs/super.c:1367
> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> vfs_get_tree+0x86/0x270 fs/super.c:1497
> do_new_mount fs/namespace.c:2905 [inline]
> path_mount+0x196f/0x2be0 fs/namespace.c:3235
> do_mount fs/namespace.c:3248 [inline]
> __do_sys_mount fs/namespace.c:3456 [inline]
> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> entry_SYSCALL_64_after_hwframe+0x44/0xae
> RIP: 0033:0x467b1a
> Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f60a5227fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
> RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000467b1a
> RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f60a5228000
> RBP: 00007f60a5228040 R08: 00007f60a5228040 R09: 0000000020000000
> R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
> R13: 0000000020000100 R14: 00007f60a5228000 R15: 0000000020014b00
> ==================================================================
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at [email protected].
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/0000000000003f654905c168b09d%40google.com.
+Cc more people who recently touched f2fs
On Mon, 3 May 2021 at 10:27, 'Dmitry Vyukov' via syzkaller-bugs
<[email protected]> wrote:
> On Mon, May 3, 2021 at 10:24 AM syzbot <[email protected]> wrote:
> >
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit: d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
> > git tree: upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=15f19ca5d00000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=53fdf14defd48c56
> > dashboard link: https://syzkaller.appspot.com/bug?extid=9d90dad32dd9727ed084
> > compiler: Debian clang version 11.0.1-2
> >
> > Unfortunately, I don't have any reproducer for this issue yet.
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: [email protected]
>
> This looks like a bug in F2FS.
> Interestingly this was detected by ARM MTE before but was
> mis-root-caused I think:
> https://lore.kernel.org/lkml/[email protected]/
> This can't be detected by KASAN directly because it doesn't instrument
> mm/slab*. This can only be detected by MTE/KFENCE.
>
> > ==================================================================
> > BUG: KFENCE: use-after-free write in kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
> >
> > Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
> > kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
> > f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
This looks like a double-kmem_cache_destroy of fsync_entry_slab in the
f2fs code. But looking at this code briefly, I couldn't say what the
fix would be.
> > f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> > mount_bdev+0x26c/0x3a0 fs/super.c:1367
> > legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> > vfs_get_tree+0x86/0x270 fs/super.c:1497
> > do_new_mount fs/namespace.c:2905 [inline]
> > path_mount+0x196f/0x2be0 fs/namespace.c:3235
> > do_mount fs/namespace.c:3248 [inline]
> > __do_sys_mount fs/namespace.c:3456 [inline]
> > __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> > do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> > entry_SYSCALL_64_after_hwframe+0x44/0xae
> >
> > kfence-#10 [0xffff88823bc16000-0xffff88823bc160df, size=224, cache=kmem_cache] allocated by task 15453:
> > kmem_cache_zalloc include/linux/slab.h:676 [inline]
> > create_cache mm/slab_common.c:247 [inline]
> > kmem_cache_create_usercopy+0x12a/0x2f0 mm/slab_common.c:350
> > kmem_cache_create+0xf/0x20 mm/slab_common.c:405
> > f2fs_kmem_cache_create fs/f2fs/f2fs.h:2463 [inline]
> > f2fs_recover_fsync_data+0x1f0/0x8380 fs/f2fs/recovery.c:790
> > f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> > mount_bdev+0x26c/0x3a0 fs/super.c:1367
> > legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> > vfs_get_tree+0x86/0x270 fs/super.c:1497
> > do_new_mount fs/namespace.c:2905 [inline]
> > path_mount+0x196f/0x2be0 fs/namespace.c:3235
> > do_mount fs/namespace.c:3248 [inline]
> > __do_sys_mount fs/namespace.c:3456 [inline]
> > __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> > do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> > entry_SYSCALL_64_after_hwframe+0x44/0xae
> >
> > freed by task 15448:
> > kobject_cleanup+0x1c9/0x280 lib/kobject.c:705
> > shutdown_cache mm/slab_common.c:463 [inline]
> > kmem_cache_destroy+0x93/0x120 mm/slab_common.c:492
> > f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
> > f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> > mount_bdev+0x26c/0x3a0 fs/super.c:1367
> > legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> > vfs_get_tree+0x86/0x270 fs/super.c:1497
> > do_new_mount fs/namespace.c:2905 [inline]
> > path_mount+0x196f/0x2be0 fs/namespace.c:3235
> > do_mount fs/namespace.c:3248 [inline]
> > __do_sys_mount fs/namespace.c:3456 [inline]
> > __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> > do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> > entry_SYSCALL_64_after_hwframe+0x44/0xae
> >
> > CPU: 0 PID: 15453 Comm: syz-executor.0 Not tainted 5.12.0-syzkaller #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> > RIP: 0010:kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:488
> > Code: 0f 1f 84 00 00 00 00 00 0f 1f 00 48 85 ff 0f 84 09 01 00 00 41 57 41 56 53 48 89 fb 48 c7 c7 b8 07 dc 8c 31 f6 e8 b1 c3 00 08 <ff> 4b 40 0f 85 c0 00 00 00 48 89 df e8 20 a2 14 00 48 89 df e8 18
> > RSP: 0018:ffffc900030af320 EFLAGS: 00010286
> > RAX: 0000000000000000 RBX: ffff88823bc16000 RCX: 0000000000000001
> > RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
> > RBP: ffffc900030af870 R08: dffffc0000000000 R09: fffffbfff19b80f8
> > R10: fffffbfff19b80f8 R11: 0000000000000000 R12: ffff88808c3a4000
> > R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000615eb0
> > FS: 00007f60a5228700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: ffff88823bc16040 CR3: 000000001ccd8000 CR4: 00000000001526f0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> > f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
> > f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
> > mount_bdev+0x26c/0x3a0 fs/super.c:1367
> > legacy_get_tree+0xea/0x180 fs/fs_context.c:592
> > vfs_get_tree+0x86/0x270 fs/super.c:1497
> > do_new_mount fs/namespace.c:2905 [inline]
> > path_mount+0x196f/0x2be0 fs/namespace.c:3235
> > do_mount fs/namespace.c:3248 [inline]
> > __do_sys_mount fs/namespace.c:3456 [inline]
> > __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
> > do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
> > entry_SYSCALL_64_after_hwframe+0x44/0xae
> > RIP: 0033:0x467b1a
> > Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
> > RSP: 002b:00007f60a5227fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
> > RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000467b1a
> > RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f60a5228000
> > RBP: 00007f60a5228040 R08: 00007f60a5228040 R09: 0000000020000000
> > R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
> > R13: 0000000020000100 R14: 00007f60a5228000 R15: 0000000020014b00
> > ==================================================================
> >
> >
> > ---
> > This report is generated by a bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for more information about syzbot.
> > syzbot engineers can be reached at [email protected].
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
Hi Macro,
I've figured out a patch for this issue.
https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git/commit/?h=dev&id=cad83c968c2ebe97905f900326988ed37146c347
Thanks,
On 2021/5/18 19:14, Marco Elver wrote:
> +Cc more people who recently touched f2fs
>
> On Mon, 3 May 2021 at 10:27, 'Dmitry Vyukov' via syzkaller-bugs
> <[email protected]> wrote:
>> On Mon, May 3, 2021 at 10:24 AM syzbot <[email protected]> wrote:
>>>
>>> Hello,
>>>
>>> syzbot found the following issue on:
>>>
>>> HEAD commit: d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
>>> git tree: upstream
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=15f19ca5d00000
>>> kernel config: https://syzkaller.appspot.com/x/.config?x=53fdf14defd48c56
>>> dashboard link: https://syzkaller.appspot.com/bug?extid=9d90dad32dd9727ed084
>>> compiler: Debian clang version 11.0.1-2
>>>
>>> Unfortunately, I don't have any reproducer for this issue yet.
>>>
>>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>>> Reported-by: [email protected]
>>
>> This looks like a bug in F2FS.
>> Interestingly this was detected by ARM MTE before but was
>> mis-root-caused I think:
>> https://lore.kernel.org/lkml/[email protected]/
>> This can't be detected by KASAN directly because it doesn't instrument
>> mm/slab*. This can only be detected by MTE/KFENCE.
>>
>>> ==================================================================
>>> BUG: KFENCE: use-after-free write in kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
>>>
>>> Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
>>> kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
>>> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
>
> This looks like a double-kmem_cache_destroy of fsync_entry_slab in the
> f2fs code. But looking at this code briefly, I couldn't say what the
> fix would be.
>
>>> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
>>> mount_bdev+0x26c/0x3a0 fs/super.c:1367
>>> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
>>> vfs_get_tree+0x86/0x270 fs/super.c:1497
>>> do_new_mount fs/namespace.c:2905 [inline]
>>> path_mount+0x196f/0x2be0 fs/namespace.c:3235
>>> do_mount fs/namespace.c:3248 [inline]
>>> __do_sys_mount fs/namespace.c:3456 [inline]
>>> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
>>> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>>
>>> kfence-#10 [0xffff88823bc16000-0xffff88823bc160df, size=224, cache=kmem_cache] allocated by task 15453:
>>> kmem_cache_zalloc include/linux/slab.h:676 [inline]
>>> create_cache mm/slab_common.c:247 [inline]
>>> kmem_cache_create_usercopy+0x12a/0x2f0 mm/slab_common.c:350
>>> kmem_cache_create+0xf/0x20 mm/slab_common.c:405
>>> f2fs_kmem_cache_create fs/f2fs/f2fs.h:2463 [inline]
>>> f2fs_recover_fsync_data+0x1f0/0x8380 fs/f2fs/recovery.c:790
>>> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
>>> mount_bdev+0x26c/0x3a0 fs/super.c:1367
>>> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
>>> vfs_get_tree+0x86/0x270 fs/super.c:1497
>>> do_new_mount fs/namespace.c:2905 [inline]
>>> path_mount+0x196f/0x2be0 fs/namespace.c:3235
>>> do_mount fs/namespace.c:3248 [inline]
>>> __do_sys_mount fs/namespace.c:3456 [inline]
>>> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
>>> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>>
>>> freed by task 15448:
>>> kobject_cleanup+0x1c9/0x280 lib/kobject.c:705
>>> shutdown_cache mm/slab_common.c:463 [inline]
>>> kmem_cache_destroy+0x93/0x120 mm/slab_common.c:492
>>> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
>>> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
>>> mount_bdev+0x26c/0x3a0 fs/super.c:1367
>>> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
>>> vfs_get_tree+0x86/0x270 fs/super.c:1497
>>> do_new_mount fs/namespace.c:2905 [inline]
>>> path_mount+0x196f/0x2be0 fs/namespace.c:3235
>>> do_mount fs/namespace.c:3248 [inline]
>>> __do_sys_mount fs/namespace.c:3456 [inline]
>>> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
>>> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>>
>>> CPU: 0 PID: 15453 Comm: syz-executor.0 Not tainted 5.12.0-syzkaller #0
>>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
>>> RIP: 0010:kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:488
>>> Code: 0f 1f 84 00 00 00 00 00 0f 1f 00 48 85 ff 0f 84 09 01 00 00 41 57 41 56 53 48 89 fb 48 c7 c7 b8 07 dc 8c 31 f6 e8 b1 c3 00 08 <ff> 4b 40 0f 85 c0 00 00 00 48 89 df e8 20 a2 14 00 48 89 df e8 18
>>> RSP: 0018:ffffc900030af320 EFLAGS: 00010286
>>> RAX: 0000000000000000 RBX: ffff88823bc16000 RCX: 0000000000000001
>>> RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
>>> RBP: ffffc900030af870 R08: dffffc0000000000 R09: fffffbfff19b80f8
>>> R10: fffffbfff19b80f8 R11: 0000000000000000 R12: ffff88808c3a4000
>>> R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000615eb0
>>> FS: 00007f60a5228700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>> CR2: ffff88823bc16040 CR3: 000000001ccd8000 CR4: 00000000001526f0
>>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>>> Call Trace:
>>> f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
>>> f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
>>> mount_bdev+0x26c/0x3a0 fs/super.c:1367
>>> legacy_get_tree+0xea/0x180 fs/fs_context.c:592
>>> vfs_get_tree+0x86/0x270 fs/super.c:1497
>>> do_new_mount fs/namespace.c:2905 [inline]
>>> path_mount+0x196f/0x2be0 fs/namespace.c:3235
>>> do_mount fs/namespace.c:3248 [inline]
>>> __do_sys_mount fs/namespace.c:3456 [inline]
>>> __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
>>> do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>> RIP: 0033:0x467b1a
>>> Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
>>> RSP: 002b:00007f60a5227fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
>>> RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000467b1a
>>> RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f60a5228000
>>> RBP: 00007f60a5228040 R08: 00007f60a5228040 R09: 0000000020000000
>>> R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
>>> R13: 0000000020000100 R14: 00007f60a5228000 R15: 0000000020014b00
>>> ==================================================================
>>>
>>>
>>> ---
>>> This report is generated by a bot. It may contain errors.
>>> See https://goo.gl/tpsmEJ for more information about syzbot.
>>> syzbot engineers can be reached at [email protected].
>>>
>>> syzbot will keep track of this issue. See:
>>> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
On Tue, 18 May 2021 at 16:26, Chao Yu <[email protected]> wrote:
> Hi Macro,
>
> I've figured out a patch for this issue.
>
> https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git/commit/?h=dev&id=cad83c968c2ebe97905f900326988ed37146c347
Ah, nice, thank you!
I wasn't sure if there had already been a fix, so I just wanted to follow up.
#syz fix: f2fs: fix to avoid racing on fsync_entry_slab by multi
filesystem instances
Thanks,
-- Marco
[-Cc most to avoid spam]
> > https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git/commit/?h=dev&id=cad83c968c2ebe97905f900326988ed37146c347
>
> Ah, nice, thank you!
> I wasn't sure if there had already been a fix, so I just wanted to follow up.
Let's try again without the line break that GMail introduces...
#syz fix: f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances