[v6.1] general protection fault in bfs_get_block

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b29299e5f60 Linux 6.1.22
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1022e63ec80000
kernel config: https://syzkaller.appspot.com/x/.config?x=4a782518325cb082
dashboard link: https://syzkaller.appspot.com/bug?extid=3b7bfa480e59af94f896
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17bb02c9c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=119fb095c80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f6cdeb0f8946/disk-3b29299e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cc5e0da6e9ab/vmlinux-3b29299e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9e31f151a6a5/bzImage-3b29299e.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/27f484556c3d/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3b7bfa...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 0 PID: 3652 Comm: syz-executor319 Not tainted 6.1.22-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:bfs_move_block fs/bfs/file.c:42 [inline]
RIP: 0010:bfs_move_blocks fs/bfs/file.c:56 [inline]
RIP: 0010:bfs_get_block+0x7f4/0xac0 fs/bfs/file.c:125
Code: 08 4c 89 f7 e8 dd 61 86 ff 41 8b 16 48 89 ef 48 89 de b9 08 00 00 00 e8 fa 3c a5 ff 49 89 c6 48 8d 58 28 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 ad 61 86 ff 48 8b 2b 49 8d 7d 28
RSP: 0018:ffffc90003d5eaf8 EFLAGS: 00010206
RAX: 0000000000000005 RBX: 0000000000000028 RCX: ffff88807ade57c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888012844d00 R08: ffffffff81ff0664 R09: fffff94000388077
R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000000002a
R13: ffff88807153e488 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000555556d31300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000077bfc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__block_write_begin_int+0x544/0x1a30 fs/buffer.c:1991
__block_write_begin fs/buffer.c:2041 [inline]
block_write_begin+0x98/0x1f0 fs/buffer.c:2102
bfs_write_begin+0x31/0xd0 fs/bfs/file.c:177
generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3754
__generic_file_write_iter+0x176/0x400 mm/filemap.c:3882
generic_file_write_iter+0xab/0x310 mm/filemap.c:3914
__kernel_write_iter+0x2ff/0x710 fs/read_write.c:517
__kernel_write+0x11c/0x170 fs/read_write.c:537
__dump_emit+0x232/0x350 fs/coredump.c:804
writenote+0x21d/0x3b0 fs/binfmt_elf.c:1488
write_note_info fs/binfmt_elf.c:1956 [inline]
elf_core_dump+0x30df/0x45b0 fs/binfmt_elf.c:2299
do_coredump+0x18b7/0x2700 fs/coredump.c:755
get_signal+0x1454/0x17d0 kernel/signal.c:2844
arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:869
exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:310
exc_page_fault+0x4e0/0x790 arch/x86/mm/fault.c:1578
asm_exc_page_fault+0x22/0x30 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: 0000000000000015 RCX: 00007facd9d13f69
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00007fffd23e0118 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffd23e0140
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bfs_move_block fs/bfs/file.c:42 [inline]
RIP: 0010:bfs_move_blocks fs/bfs/file.c:56 [inline]
RIP: 0010:bfs_get_block+0x7f4/0xac0 fs/bfs/file.c:125
Code: 08 4c 89 f7 e8 dd 61 86 ff 41 8b 16 48 89 ef 48 89 de b9 08 00 00 00 e8 fa 3c a5 ff 49 89 c6 48 8d 58 28 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 ad 61 86 ff 48 8b 2b 49 8d 7d 28
RSP: 0018:ffffc90003d5eaf8 EFLAGS: 00010206
RAX: 0000000000000005 RBX: 0000000000000028 RCX: ffff88807ade57c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888012844d00 R08: ffffffff81ff0664 R09: fffff94000388077
R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000000002a
R13: ffff88807153e488 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000555556d31300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffd23dffe8 CR3: 0000000077bfc000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 08 4c 89 f7 or %cl,-0x9(%rcx,%rcx,4)
4: e8 dd 61 86 ff callq 0xff8661e6
9: 41 8b 16 mov (%r14),%edx
c: 48 89 ef mov %rbp,%rdi
f: 48 89 de mov %rbx,%rsi
12: b9 08 00 00 00 mov $0x8,%ecx
17: e8 fa 3c a5 ff callq 0xffa53d16
1c: 49 89 c6 mov %rax,%r14
1f: 48 8d 58 28 lea 0x28(%rax),%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 ad 61 86 ff callq 0xff8661e6
39: 48 8b 2b mov (%rbx),%rbp
3c: 49 8d 7d 28 lea 0x28(%r13),%rdi


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