[v5.15] UBSAN: shift-out-of-bounds in dbDiscardAG

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7e89efd3ae1c Linux 5.15.164
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1071fbc9980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ef3d6716c47442fa
dashboard link: https://syzkaller.appspot.com/bug?extid=44479088a2c9bdc8e2a7
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/39cf3e32ff98/disk-7e89efd3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5832802d8e4b/vmlinux-7e89efd3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fe6dc074e0ff/bzImage-7e89efd3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+444790...@syzkaller.appspotmail.com

================================================================================
UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:1697:18
shift exponent -1 is negative
CPU: 1 PID: 10316 Comm: syz.4.2395 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:151 [inline]
__ubsan_handle_shift_out_of_bounds+0x3bf/0x420 lib/ubsan.c:321
dbDiscardAG+0x5a3/0xa10 fs/jfs/jfs_dmap.c:1697
jfs_ioc_trim+0x42f/0x660 fs/jfs/jfs_discard.c:100
jfs_ioctl+0x2ac/0x3a0 fs/jfs/ioctl.c:132
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7feb2bfbc9f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feb2a43b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007feb2c14af80 RCX: 00007feb2bfbc9f9
RDX: 0000000020000080 RSI: 00000000c0185879 RDI: 000000000000000b
RBP: 00007feb2c02a8ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007feb2c14af80 R15: 00007ffee4e81038
</TASK>
================================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 3a5928702e71 Linux 5.15.167
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=109cb507980000
kernel config: https://syzkaller.appspot.com/x/.config?x=171882977b524c53

dashboard link: https://syzkaller.appspot.com/bug?extid=44479088a2c9bdc8e2a7
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16814d9f980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1622a6a9980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/22ee27cb312d/disk-3a592870.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/90bf6a3e3d20/vmlinux-3a592870.xz
kernel image: https://storage.googleapis.com/syzbot-assets/096dd2c73ac3/Image-3a592870.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/8f1641e3601b/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+444790...@syzkaller.appspotmail.com

option from the mount to silence this warning.
=======================================================

================================================================================
UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:1697:18
shift exponent -1 is negative

CPU: 0 PID: 4019 Comm: syz-executor379 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call trace:
dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
dump_stack+0x1c/0x58 lib/dump_stack.c:113
ubsan_epilogue lib/ubsan.c:151 [inline]
__ubsan_handle_shift_out_of_bounds+0x2f8/0x378 lib/ubsan.c:321
dbDiscardAG+0x3a4/0x728 fs/jfs/jfs_dmap.c:1697
jfs_ioc_trim+0x3cc/0x5d8 fs/jfs/jfs_discard.c:100
jfs_ioctl+0x350/0x574 fs/jfs/ioctl.c:132

vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]

__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a


---
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