On Tue, Nov 05, 2024 at 05:23:23PM -0800, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 59b723cd2adb Linux 6.12-rc6 > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1076c740580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=b77c8a55ccf1d9e2 > dashboard link: https://syzkaller.appspot.com/bug?extid=078be8bfa863cb9e0c6b > 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=167aa1f7980000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110d86a7980000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/699c7100a12a/disk-59b723cd.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/74524a66d4bc/vmlinux-59b723cd.xz > kernel image: https://storage.googleapis.com/syzbot-assets/e81ed2bba0ef/bzImage-59b723cd.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+078be8bfa863cb9e0c6b@xxxxxxxxxxxxxxxxxxxxxxxxx > > Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI > KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] > CPU: 1 UID: 0 PID: 51 Comm: kworker/1:1 Not tainted 6.12.0-rc6-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > Workqueue: events swap_reclaim_work > RIP: 0010:__list_del_entry_valid_or_report+0x20/0x1c0 lib/list_debug.c:49 > Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 fe 48 83 c7 08 48 83 ec 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 19 01 00 00 48 89 f2 48 8b 4e 08 48 b8 00 00 00 > RSP: 0018:ffffc90000bb7c30 EFLAGS: 00010202 > RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88807b9ae078 > RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000008 > RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 > R10: 0000000000000001 R11: 000000000000004f R12: dffffc0000000000 > R13: ffffffffffffffb8 R14: ffff88807b9ae000 R15: ffffc90003af1000 > FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007fffaca68fb8 CR3: 00000000791c8000 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_move_tail include/linux/list.h:310 [inline] > swap_reclaim_full_clusters+0x109/0x460 mm/swapfile.c:748 > swap_reclaim_work+0x2e/0x40 mm/swapfile.c:779 > process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 > process_scheduled_works kernel/workqueue.c:3310 [inline] > worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 > kthread+0x2c1/0x3a0 kernel/kthread.c:389 > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > </TASK> > Modules linked in: > ---[ end trace 0000000000000000 ]--- > RIP: 0010:__list_del_entry_valid_or_report+0x20/0x1c0 lib/list_debug.c:49 > Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 fe 48 83 c7 08 48 83 ec 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 19 01 00 00 48 89 f2 48 8b 4e 08 48 b8 00 00 00 > RSP: 0018:ffffc90000bb7c30 EFLAGS: 00010202 > RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88807b9ae078 > RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000008 > RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 > R10: 0000000000000001 R11: 000000000000004f R12: dffffc0000000000 > R13: ffffffffffffffb8 R14: ffff88807b9ae000 R15: ffffc90003af1000 > FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007fffaca68fb8 CR3: 00000000791c8000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > ---------------- > Code disassembly (best guess): > 0: 90 nop > 1: 90 nop > 2: 90 nop > 3: 90 nop > 4: 90 nop > 5: 90 nop > 6: 90 nop > 7: 90 nop > 8: 90 nop > 9: 90 nop > a: f3 0f 1e fa endbr64 > e: 48 89 fe mov %rdi,%rsi > 11: 48 83 c7 08 add $0x8,%rdi > 15: 48 83 ec 18 sub $0x18,%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 19 01 00 00 jne 0x14d > 34: 48 89 f2 mov %rsi,%rdx > 37: 48 8b 4e 08 mov 0x8(%rsi),%rcx > 3b: 48 rex.W > 3c: b8 .byte 0xb8 > 3d: 00 00 add %al,(%rax) > > This should fix it: ---