Hello, syzbot found the following issue on: HEAD commit: 98b1cc82c4af Linux 6.7-rc2 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1427ba00e80000 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 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16783b84e80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=165172a0e80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/b60687e82ad4/disk-98b1cc82.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/29477f0b04df/vmlinux-98b1cc82.xz kernel image: https://storage.googleapis.com/syzbot-assets/9aab12888a60/bzImage-98b1cc82.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/58e57ae1d84f/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+dc6ed11a88fb40d6e184@xxxxxxxxxxxxxxxxxxxxxxxxx Code: Unable to access opcode bytes at 0xffffffffffffffd6. general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 PID: 5059 Comm: syz-executor306 Not tainted 6.7.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 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+0x3b2/0xeb0 fs/bfs/file.c:125 Code: a8 ff 48 8d 7d 20 48 89 c3 48 89 f8 48 c1 e8 03 42 80 3c 28 00 0f 85 5b 08 00 00 48 8d 7b 28 48 8b 55 20 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 dd 08 00 00 48 8d 7d 28 48 8b 43 28 48 89 f9 RSP: 0018:ffffc900033fef30 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 0000000000000000 RCX: ffffffff81fd2b77 RDX: 0000000000000200 RSI: ffffffff81fd2e15 RDI: 0000000000000028 RBP: ffff888074ee20e8 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000fffffffa R11: 0000000000000003 R12: 0000000000000019 R13: dffffc0000000000 R14: ffff88807fb36000 R15: ffffed100ff66c2c FS: 0000555556c24380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6250121b3b CR3: 000000001f25d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __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:177 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 writenote+0x215/0x2b0 fs/binfmt_elf.c:1422 write_note_info fs/binfmt_elf.c:1897 [inline] elf_core_dump+0x250c/0x3900 fs/binfmt_elf.c:2064 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: 0000000000000020 RCX: 00007f3fa02f7db9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000555500000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000f4240 R13: 00007ffdb733b1e8 R14: 0000000000000001 R15: 00007ffdb733afb0 </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+0x3b2/0xeb0 fs/bfs/file.c:125 Code: a8 ff 48 8d 7d 20 48 89 c3 48 89 f8 48 c1 e8 03 42 80 3c 28 00 0f 85 5b 08 00 00 48 8d 7b 28 48 8b 55 20 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 dd 08 00 00 48 8d 7d 28 48 8b 43 28 48 89 f9 RSP: 0018:ffffc900033fef30 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 0000000000000000 RCX: ffffffff81fd2b77 RDX: 0000000000000200 RSI: ffffffff81fd2e15 RDI: 0000000000000028 RBP: ffff888074ee20e8 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000fffffffa R11: 0000000000000003 R12: 0000000000000019 R13: dffffc0000000000 R14: ffff88807fb36000 R15: ffffed100ff66c2c FS: 0000555556c24380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000001f25d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: a8 ff test $0xff,%al 2: 48 8d 7d 20 lea 0x20(%rbp),%rdi 6: 48 89 c3 mov %rax,%rbx 9: 48 89 f8 mov %rdi,%rax c: 48 c1 e8 03 shr $0x3,%rax 10: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 15: 0f 85 5b 08 00 00 jne 0x876 1b: 48 8d 7b 28 lea 0x28(%rbx),%rdi 1f: 48 8b 55 20 mov 0x20(%rbp),%rdx 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 0f 85 dd 08 00 00 jne 0x912 35: 48 8d 7d 28 lea 0x28(%rbp),%rdi 39: 48 8b 43 28 mov 0x28(%rbx),%rax 3d: 48 89 f9 mov %rdi,%rcx --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
