Hello, syzbot found the following issue on: HEAD commit: ae230642190a Merge branch 'af_unix-followup-fixes-for-so_p.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=11fe4cb8a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=c9bf1936936ca698 dashboard link: https://syzkaller.appspot.com/bug?extid=689ec3afb1ef07b766b2 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=136b9d48a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10223cb8a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8c060db03f09/disk-ae230642.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/1b9b937ece91/vmlinux-ae230642.xz kernel image: https://storage.googleapis.com/syzbot-assets/0c7eb1c82bf0/bzImage-ae230642.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+689ec3afb1ef07b766b2@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 2858 Comm: kworker/u4:5 Not tainted 6.4.0-rc7-syzkaller-01948-gae230642190a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work RIP: 0010:_compound_head include/linux/page-flags.h:245 [inline] RIP: 0010:bio_first_folio include/linux/bio.h:284 [inline] RIP: 0010:ext4_finish_bio+0xdc/0x1090 fs/ext4/page-io.c:104 Code: c1 ea 03 80 3c 02 00 0f 85 43 0f 00 00 48 8b 45 00 48 8d 78 08 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4c 0f 00 00 48 8b 04 24 31 ff 4c 8b 60 08 4c 89 RSP: 0018:ffffc9000d047b60 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff8234c972 RDI: 0000000000000008 RBP: ffff88807d609100 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000094001 R12: ffff888074f111e0 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff888074c416b0 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020241040 CR3: 0000000024e17000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ext4_release_io_end+0x118/0x3b0 fs/ext4/page-io.c:160 ext4_end_io_end fs/ext4/page-io.c:194 [inline] ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline] ext4_end_io_rsv_work+0x156/0x670 fs/ext4/page-io.c:273 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:_compound_head include/linux/page-flags.h:245 [inline] RIP: 0010:bio_first_folio include/linux/bio.h:284 [inline] RIP: 0010:ext4_finish_bio+0xdc/0x1090 fs/ext4/page-io.c:104 Code: c1 ea 03 80 3c 02 00 0f 85 43 0f 00 00 48 8b 45 00 48 8d 78 08 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4c 0f 00 00 48 8b 04 24 31 ff 4c 8b 60 08 4c 89 RSP: 0018:ffffc9000d047b60 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff8234c972 RDI: 0000000000000008 RBP: ffff88807d609100 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000094001 R12: ffff888074f111e0 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff888074c416b0 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020241040 CR3: 000000007a4d9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: c1 ea 03 shr $0x3,%edx 3: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 7: 0f 85 43 0f 00 00 jne 0xf50 d: 48 8b 45 00 mov 0x0(%rbp),%rax 11: 48 8d 78 08 lea 0x8(%rax),%rdi 15: 48 89 04 24 mov %rax,(%rsp) 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 4c 0f 00 00 jne 0xf80 34: 48 8b 04 24 mov (%rsp),%rax 38: 31 ff xor %edi,%edi 3a: 4c 8b 60 08 mov 0x8(%rax),%r12 3e: 4c rex.WR 3f: 89 .byte 0x89 --- This report is generated by a bot. 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