Hello, We found the following issue using syzkaller on Linux v6.10. When `to_shrink_list` tried to delete dentry via `d_lru_del(dentry)`, a list corruption happened. Unfortunately, the syzkaller failed to generate a reproducer. But at least we have the report: list_del corruption. prev->next should be ffff88802c7c32a0, but was 0000000000000000. (prev=ffff88803d1de410) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:64! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 PID: 8670 Comm: syz-executor Not tainted 6.10.0 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__list_del_entry_valid_or_report+0x10a/0x120 lib/list_debug.c:62 Code: e8 bb ff 96 06 0f 0b 48 c7 c7 80 5b a9 8b 4c 89 fe e8 aa ff 96 06 0f 0b 48 c7 c7 e0 5b a9 8b 4c 89 fe 48 89 d9 e8 96 ff 96 06 <0f> 0b 48 c7 c7 60 5c a9 8b 4c 89 fe 4c 89 f1 e8 82 ff 96 06 0f 0b RSP: 0000:ffffc9000ad77428 EFLAGS: 00010246 RAX: 000000000000006d RBX: ffff88803d1de410 RCX: 4740cdb9afd41600 RDX: 0000000000000000 RSI: 0000000080000003 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff8172e30c R09: 1ffff920015aee24 R10: dffffc0000000000 R11: fffff520015aee25 R12: dffffc0000000000 R13: ffff88803cf85000 R14: ffff88803d1de410 R15: ffff88802c7c32a0 FS: 000055555bfe4500(0000) GS:ffff888063a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562d00112406 CR3: 0000000040714000 CR4: 0000000000350ef0 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_del_init include/linux/list.h:287 [inline] list_lru_del+0x177/0x300 mm/list_lru.c:129 d_lru_del fs/dcache.c:445 [inline] to_shrink_list+0x133/0x330 fs/dcache.c:868 select_collect+0xc8/0x1a0 fs/dcache.c:1436 d_walk+0x1d3/0x710 fs/dcache.c:1259 shrink_dcache_parent+0x140/0x3b0 fs/dcache.c:1491 d_invalidate+0x117/0x2e0 fs/dcache.c:1596 proc_invalidate_siblings_dcache+0x3af/0x6c0 fs/proc/inode.c:142 release_task+0x1619/0x1910 kernel/exit.c:281 wait_task_zombie kernel/exit.c:1187 [inline] wait_consider_task+0x19f0/0x2e10 kernel/exit.c:1414 do_wait_thread kernel/exit.c:1477 [inline] __do_wait+0x1a7/0x870 kernel/exit.c:1595 do_wait+0x228/0x310 kernel/exit.c:1629 kernel_wait4+0x29c/0x3e0 kernel/exit.c:1788 __do_sys_wait4 kernel/exit.c:1816 [inline] __se_sys_wait4 kernel/exit.c:1812 [inline] __x64_sys_wait4+0x130/0x1e0 kernel/exit.c:1812 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x7e/0x150 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x67/0x6f RIP: 0033:0x7f69a7976c17 Code: 89 7c 24 10 48 89 4c 24 18 e8 55 15 03 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 a5 15 03 00 8b 44 RSP: 002b:00007ffe2a90f730 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 000000000000039a RCX: 00007f69a7976c17 RDX: 0000000040000000 RSI: 00007ffe2a90f78c RDI: 00000000ffffffff RBP: 00007ffe2a90f78c R08: 0000000000000000 R09: 00007f69a87c4080 R10: 0000000000000000 R11: 0000000000000293 R12: 000055555bff75eb R13: 000055555bff7590 R14: 0000000000054822 R15: 00007ffe2a90f7e0 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_del_entry_valid_or_report+0x10a/0x120 lib/list_debug.c:62 Code: e8 bb ff 96 06 0f 0b 48 c7 c7 80 5b a9 8b 4c 89 fe e8 aa ff 96 06 0f 0b 48 c7 c7 e0 5b a9 8b 4c 89 fe 48 89 d9 e8 96 ff 96 06 <0f> 0b 48 c7 c7 60 5c a9 8b 4c 89 fe 4c 89 f1 e8 82 ff 96 06 0f 0b RSP: 0000:ffffc9000ad77428 EFLAGS: 00010246 RAX: 000000000000006d RBX: ffff88803d1de410 RCX: 4740cdb9afd41600 RDX: 0000000000000000 RSI: 0000000080000003 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff8172e30c R09: 1ffff920015aee24 R10: dffffc0000000000 R11: fffff520015aee25 R12: dffffc0000000000 R13: ffff88803cf85000 R14: ffff88803d1de410 R15: ffff88802c7c32a0 FS: 000055555bfe4500(0000) GS:ffff888063a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562d00112406 CR3: 0000000040714000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
