Re: [syzbot] [media?] BUG: corrupted list in az6007_i2c_xfer

[syzbot <syzbot+0192952caa411a3be209@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: corrupted list in az6007_i2c_xfer

 slab kmalloc-8k start ffff888061394000 pointer offset 80 size 8192
list_del corruption. prev->next should be ffffc900041a7960, but was ffff888061394050. (prev=ffff888061394050)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:62!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 7547 Comm: syz.0.109 Not tainted 6.15.0-rc3-syzkaller-g9d7a0577c9db-dirty #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__list_del_entry_valid_or_report+0x17a/0x200 lib/list_debug.c:62
Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 a0 69 f4 8b e8 b7 82 c5 fc 90 <0f> 0b 4c 89 e7 e8 ec 48 29 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc900041a7870 EFLAGS: 00010086
RAX: 000000000000006d RBX: ffffc900041a7960 RCX: ffffffff819aaf39
RDX: 0000000000000000 RSI: ffffffff819b2dc6 RDI: 0000000000000005
RBP: ffff888061394050 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000002 R11: 0000000000000001 R12: ffff888061394050
R13: ffffc900041a7940 R14: 0000000000000246 R15: 1ffff92000834f22
FS:  00007f3527db26c0(0000) GS:ffff888124ab2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000025c0 CR3: 0000000028dda000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry_valid include/linux/list.h:124 [inline]
 __list_del_entry include/linux/list.h:215 [inline]
 list_del include/linux/list.h:229 [inline]
 __mutex_remove_waiter+0x1a/0x1a0 kernel/locking/mutex.c:206
 __mutex_lock_common kernel/locking/mutex.c:714 [inline]
 __mutex_lock+0x85b/0xb90 kernel/locking/mutex.c:746
 az6007_i2c_xfer+0x8e/0xc30 drivers/media/usb/dvb-usb-v2/az6007.c:755
 __i2c_transfer+0x6b3/0x2190 drivers/i2c/i2c-core-base.c:2259
 i2c_transfer drivers/i2c/i2c-core-base.c:2315 [inline]
 i2c_transfer+0x1da/0x380 drivers/i2c/i2c-core-base.c:2291
 i2c_transfer_buffer_flags+0x10c/0x190 drivers/i2c/i2c-core-base.c:2343
 i2c_master_recv include/linux/i2c.h:79 [inline]
 i2cdev_read+0x111/0x280 drivers/i2c/i2c-dev.c:155
 do_loop_readv_writev fs/read_write.c:845 [inline]
 do_loop_readv_writev fs/read_write.c:833 [inline]
 vfs_readv+0x6bc/0x8a0 fs/read_write.c:1018
 do_preadv+0x1af/0x270 fs/read_write.c:1130
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3526f8e169
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:00007f3527db2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007f35271b5fa0 RCX: 00007f3526f8e169
RDX: 0000000000000001 RSI: 00002000000025c0 RDI: 0000000000000004
RBP: 00007f3527010a68 R08: 000000000000007e R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f35271b5fa0 R15: 00007ffcd08bc1d8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid_or_report+0x17a/0x200 lib/list_debug.c:62
Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 a0 69 f4 8b e8 b7 82 c5 fc 90 <0f> 0b 4c 89 e7 e8 ec 48 29 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc900041a7870 EFLAGS: 00010086
RAX: 000000000000006d RBX: ffffc900041a7960 RCX: ffffffff819aaf39
RDX: 0000000000000000 RSI: ffffffff819b2dc6 RDI: 0000000000000005
RBP: ffff888061394050 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000002 R11: 0000000000000001 R12: ffff888061394050
R13: ffffc900041a7940 R14: 0000000000000246 R15: 1ffff92000834f22
FS:  00007f3527db26c0(0000) GS:ffff888124ab2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000025c0 CR3: 0000000028dda000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit:         9d7a0577 gcc-15: disable '-Wunterminated-string-initia..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16dfcc70580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=efa83f9a6dd67d67
dashboard link: https://syzkaller.appspot.com/bug?extid=0192952caa411a3be209
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14c78fcf980000