Re: [syzbot] [bfs?] general protection fault in bfs_get_block (2)

[syzbot <syzbot+dc6ed11a88fb40d6e184@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in mark_buffer_dirty

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5488 at fs/buffer.c:1176 mark_buffer_dirty+0x37b/0x3f0 fs/buffer.c:1176
Modules linked in:
CPU: 0 PID: 5488 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00265-gd2da77f431ac-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:mark_buffer_dirty+0x37b/0x3f0 fs/buffer.c:1176
Code: 89 ff e8 78 cb 89 ff 48 89 ef e8 50 6a e7 ff 5b 5d e9 69 cb 89 ff e8 64 cb 89 ff 90 0f 0b 90 e9 0c fe ff ff e8 56 cb 89 ff 90 <0f> 0b 90 e9 b1 fc ff ff e8 48 cb 89 ff 90 0f 0b 90 e9 ce fc ff ff
RSP: 0018:ffffc9000381efc8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888070b933e0 RCX: ffffffff81fcb1bb
RDX: ffff888029eec100 RSI: ffffffff81fcb50a RDI: 0000000000000001
RBP: ffff888070b93300 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000013
R13: dffffc0000000000 R14: ffff888029be2000 R15: ffffed100537c403
FS:  00007fe0721f36c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000001ffffe40 CR3: 0000000029e95000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bfs_move_block fs/bfs/file.c:48 [inline]
 bfs_move_blocks fs/bfs/file.c:61 [inline]
 bfs_get_block+0x41b/0xe90 fs/bfs/file.c:130
 __block_write_begin_int+0x3c0/0x1560 fs/buffer.c:2119
 __block_write_begin fs/buffer.c:2168 [inline]
 block_write_begin+0xb1/0x490 fs/buffer.c:2227
 bfs_write_begin+0x31/0xd0 fs/bfs/file.c:182
 generic_perform_write+0x278/0x600 mm/filemap.c:3918
 __generic_file_write_iter+0x1f9/0x240 mm/filemap.c:4013
 generic_file_write_iter+0xe3/0x350 mm/filemap.c:4039
 __kernel_write_iter+0x261/0x7b0 fs/read_write.c:517
 __kernel_write+0xf6/0x140 fs/read_write.c:537
 __dump_emit fs/coredump.c:813 [inline]
 dump_emit+0x21d/0x330 fs/coredump.c:850
 elf_core_dump+0x21bc/0x3900 fs/binfmt_elf.c:2056
 do_coredump+0x2c97/0x3fd0 fs/coredump.c:764
 get_signal+0x2438/0x2790 kernel/signal.c:2890
 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x121/0x240 kernel/entry/common.c:204
 irqentry_exit_to_user_mode+0xa/0x40 kernel/entry/common.c:309
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 002b:0000000020000008 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fe07159bf80 RCX: 00007fe07147cae9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00007fe0714c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe07159bf80 R15: 00007ffe7a2118b8
 </TASK>


Tested on:

commit:         d2da77f4 Merge tag 'parisc-for-6.7-rc3' of git://git.k..
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=16ec3052e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=aec35c1281ec0aaf
dashboard link: https://syzkaller.appspot.com/bug?extid=dc6ed11a88fb40d6e184
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=146bba62e80000