[syzbot] KASAN: use-after-free Read in diFree

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 91265a6da44d Add linux-next specific files for 20220303
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=156de84d700000
kernel config: https://syzkaller.appspot.com/x/.config?x=617f79440a35673a
dashboard link: https://syzkaller.appspot.com/bug?extid=1964c915c8c3913b3d7a
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1792d44d700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12f47491700000

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10467e9d700000
final oops: https://syzkaller.appspot.com/x/report.txt?x=12467e9d700000
console output: https://syzkaller.appspot.com/x/log.txt?x=14467e9d700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1964c9...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 180
jfs_mount: dbMount failed w/rc = -5
Mount JFS Failure: -5
jfs_mount failed w/return code = -5
loop0: detected capacity change from 0 to 180
jfs_mount: diMount failed w/rc = -5
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 3828 Comm: syz-executor115 Not tainted 5.17.0-rc6-next-20220303-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:diFree+0x17f/0x2660 fs/jfs/jfs_imap.c:871
Code: 00 48 8b 44 24 18 48 8b 68 80 4c 89 e8 48 c1 e8 0c 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 4c 8d 65 04 4c 89 e2 48 c1 ea 03 <0f> b6 14 02 4c 89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 26
RSP: 0018:ffffc90003aff8e0 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffff88801ce21400 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff82ce6625 RDI: ffff8880718883b0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff82cc0f85 R11: 0000000000000000 R12: 0000000000000004
R13: 0000000000000001 R14: ffffffff8a07aa60 R15: ffff8880718a2930
FS: 00005555569f3300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e855c0720 CR3: 0000000072fcb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
jfs_evict_inode+0x392/0x470 fs/jfs/inode.c:155
evict+0x2ed/0x6b0 fs/inode.c:664
iput_final fs/inode.c:1744 [inline]
iput.part.0+0x562/0x820 fs/inode.c:1770
iput+0x58/0x70 fs/inode.c:1760
diFreeSpecial+0x73/0x100 fs/jfs/jfs_imap.c:548
jfs_mount+0x1c1/0x7b0 fs/jfs/jfs_mount.c:207
jfs_fill_super+0x5a4/0xc70 fs/jfs/super.c:560
mount_bdev+0x34d/0x410 fs/super.c:1367
legacy_get_tree+0x105/0x220 fs/fs_context.c:610
vfs_get_tree+0x89/0x2f0 fs/super.c:1497
do_new_mount fs/namespace.c:3025 [inline]
path_mount+0x1320/0x1fa0 fs/namespace.c:3355
do_mount fs/namespace.c:3368 [inline]
__do_sys_mount fs/namespace.c:3576 [inline]
__se_sys_mount fs/namespace.c:3553 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3553
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f1e855ecdba
Code: 48 c7 c2 c0 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 a8 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe2176c5d8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffe2176c640 RCX: 00007f1e855ecdba
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffe2176c600
RBP: 00007ffe2176c600 R08: 00007ffe2176c640 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000282 R12: 0000000020000260
R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000004
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:diFree+0x17f/0x2660 fs/jfs/jfs_imap.c:871
Code: 00 48 8b 44 24 18 48 8b 68 80 4c 89 e8 48 c1 e8 0c 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 4c 8d 65 04 4c 89 e2 48 c1 ea 03 <0f> b6 14 02 4c 89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 26
RSP: 0018:ffffc90003aff8e0 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffff88801ce21400 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff82ce6625 RDI: ffff8880718883b0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff82cc0f85 R11: 0000000000000000 R12: 0000000000000004
R13: 0000000000000001 R14: ffffffff8a07aa60 R15: ffff8880718a2930
FS: 00005555569f3300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e855c0720 CR3: 0000000072fcb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 00 48 8b add %cl,-0x75(%rax)
3: 44 24 18 rex.R and $0x18,%al
6: 48 8b 68 80 mov -0x80(%rax),%rbp
a: 4c 89 e8 mov %r13,%rax
d: 48 c1 e8 0c shr $0xc,%rax
11: 48 89 04 24 mov %rax,(%rsp)
15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1c: fc ff df
1f: 4c 8d 65 04 lea 0x4(%rbp),%r12
23: 4c 89 e2 mov %r12,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction
2e: 4c 89 e0 mov %r12,%rax
31: 83 e0 07 and $0x7,%eax
34: 83 c0 03 add $0x3,%eax
37: 38 d0 cmp %dl,%al
39: 7c 08 jl 0x43
3b: 84 d2 test %dl,%dl
3d: 0f .byte 0xf
3e: 85 26 test %esp,(%rsi)


---
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+1964c9...@syzkaller.appspotmail.com

Tested on:

commit: 787af64d mm: page_alloc: validate buddy before check i..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git --
kernel config: https://syzkaller.appspot.com/x/.config?x=84cc605575ae78ef

dashboard link: https://syzkaller.appspot.com/bug?extid=1964c915c8c3913b3d7a
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.