WARNING in udf_truncate_extents

From: syzbot
Date: Mon Oct 12 2020 - 09:20:21 EST


Hello,

syzbot found the following issue on:

HEAD commit: da690031 Merge branch 'i2c/for-current' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=172e2ef0500000
kernel config: https://syzkaller.appspot.com/x/.config?x=de7f697da23057c7
dashboard link: https://syzkaller.appspot.com/bug?extid=43fc5ba6dcb33e3261ca
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10ce0a8b900000

The issue was bisected to:

commit 2004bfdef945fe55196db6b9cdf321fbc75bb0de
Author: Bart Van Assche <bvanassche@xxxxxxx>
Date: Tue Mar 10 04:26:21 2020 +0000

null_blk: Fix the null_add_dev() error path

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10110920500000
final oops: https://syzkaller.appspot.com/x/report.txt?x=12110920500000
console output: https://syzkaller.appspot.com/x/log.txt?x=14110920500000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+43fc5ba6dcb33e3261ca@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 2004bfdef945 ("null_blk: Fix the null_add_dev() error path")

UDF-fs: Scanning with blocksize 512 failed
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2020/09/19 18:44 (1000)
------------[ cut here ]------------
WARNING: CPU: 1 PID: 17858 at fs/udf/truncate.c:226 udf_truncate_extents+0xf74/0x1120 fs/udf/truncate.c:226
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 17858 Comm: syz-executor.5 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d6/0x29e lib/dump_stack.c:118
panic+0x2c0/0x800 kernel/panic.c:231
__warn+0x227/0x250 kernel/panic.c:600
report_bug+0x1b1/0x2e0 lib/bug.c:198
handle_bug+0x42/0x80 arch/x86/kernel/traps.c:234
exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:254
asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:udf_truncate_extents+0xf74/0x1120 fs/udf/truncate.c:226
Code: 24 14 18 00 00 00 43 80 3c 2f 00 0f 85 63 fe ff ff e9 6b fe ff ff e8 2b 9a cd fe bb fb ff ff ff e9 27 ff ff ff e8 1c 9a cd fe <0f> 0b e9 1b ff ff ff 89 d9 80 e1 07 38 c1 0f 8c 59 f1 ff ff 48 89
RSP: 0018:ffffc90005ea7a08 EFLAGS: 00010293
RAX: ffffffff82a763d4 RBX: 0000000000000000 RCX: ffff888077582040
RDX: 0000000000000000 RSI: 0000000000000400 RDI: 0000000000000000
RBP: 0000000000000400 R08: ffffffff82a757a8 R09: ffffffff82a54d54
R10: 0000000000000002 R11: ffff888077582040 R12: 0000000005ea7aff
R13: 00000000000c2000 R14: 0000000000000308 R15: 1ffff1100e577c10
udf_write_failed fs/udf/inode.c:176 [inline]
udf_write_begin+0x1e2/0x210 fs/udf/inode.c:211
generic_perform_write+0x23b/0x4e0 mm/filemap.c:3505
__generic_file_write_iter+0x22b/0x4e0 mm/filemap.c:3634
udf_file_write_iter+0x339/0x4e0 fs/udf/file.c:169
do_iter_readv_writev+0x4f9/0x6c0 include/linux/fs.h:1876
do_iter_write+0x164/0x610 fs/read_write.c:1026
vfs_writev fs/read_write.c:1099 [inline]
do_pwritev+0x234/0x430 fs/read_write.c:1196
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de59
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4cc0709c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000128
RAX: ffffffffffffffda RBX: 0000000000026400 RCX: 000000000045de59
RDX: 0000000000000001 RSI: 00000000200014c0 RDI: 0000000000000003
RBP: 000000000118bf70 R08: 0000000000000020 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fffd7780fdf R14: 00007f4cc070a9c0 R15: 000000000118bf2c
Kernel Offset: disabled
Rebooting in 86400 seconds..


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