------------[ cut here ]------------ kernfs_put: syz0/memory.events: released with incorrect active_ref 0 WARNING: CPU: 0 PID: 6 at fs/kernfs/dir.c:531 kernfs_put.part.0+0x433/0x540 Modules linked in: CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted 5.19.0-rc4-next-20220701 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Workqueue: events kernfs_notify_workfn RIP: 0010:kernfs_put.part.0+0x433/0x540 Code: 03 80 3c 18 00 0f 85 ea 00 00 00 4d 8b 7d 38 e8 53 42 a7 ff 48 8b 14 24 44 89 f1 4c 89 fe 48 c7 c7 a0 58 72 84 e8 97 1c 6c 02 <0f> 0b e9 b9 fc ff ff 48 89 ef e8 8e b6 d9 ff e9 c1 fd ff ff e8 84 RSP: 0018:ffff888008217bd8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888008201ac0 RSI: ffffffff812b6848 RDI: ffffed1001042f6d RBP: ffff88800d768eb8 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800d768e80 R13: ffff888019652658 R14: 0000000000000000 R15: ffff88800a736050 FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa90c2082a0 CR3: 000000000e7b0000 CR4: 0000000000350ef0 Call Trace: kernfs_put+0x42/0x50 kernfs_notify_workfn+0x417/0x560 process_one_work+0xa0f/0x1690 worker_thread+0x637/0x1250 kthread+0x2ed/0x3a0 ret_from_fork+0x22/0x30 irq event stamp: 29343 hardirqs last enabled at (29355): [] __up_console_sem+0x78/0x80 hardirqs last disabled at (29366): [] __up_console_sem+0x5d/0x80 softirqs last enabled at (29160): [] __irq_exit_rcu+0x113/0x170 softirqs last disabled at (29137): [] __irq_exit_rcu+0x113/0x170 ---[ end trace 0000000000000000 ]--- ================================================================== BUG: KASAN: use-after-free in llist_del_first+0x89/0xa0 Read of size 8 at addr ffff88800d768f00 by task kworker/0:0/6 CPU: 0 PID: 6 Comm: kworker/0:0 Tainted: G W 5.19.0-rc4-next-20220701 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Workqueue: events kernfs_notify_workfn Call Trace: dump_stack_lvl+0x8b/0xb3 print_report.cold+0x5e/0x5e1 kasan_report+0xb1/0x1b0 llist_del_first+0x89/0xa0 kernfs_notify_workfn+0x78/0x560 process_one_work+0xa0f/0x1690 worker_thread+0x637/0x1250 kthread+0x2ed/0x3a0 ret_from_fork+0x22/0x30 Allocated by task 297: kasan_save_stack+0x1e/0x40 __kasan_slab_alloc+0x66/0x80 kmem_cache_alloc+0x1b1/0x490 __kernfs_new_node+0xd4/0x8b0 kernfs_new_node+0x93/0x120 __kernfs_create_file+0x51/0x350 cgroup_addrm_files+0x3e2/0x9d0 css_populate_dir+0x19b/0x450 cgroup_apply_control_enable+0x3ae/0xa40 cgroup_mkdir+0x824/0x11f0 kernfs_iop_mkdir+0x149/0x1d0 vfs_mkdir+0x417/0x6a0 do_mkdirat+0x17b/0x2e0 __x64_sys_mkdir+0xf2/0x140 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Freed by task 6: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0x108/0x190 kmem_cache_free+0xfb/0x600 kernfs_put.part.0+0x2c7/0x540 kernfs_put+0x42/0x50 kernfs_notify_workfn+0x417/0x560 process_one_work+0xa0f/0x1690 worker_thread+0x637/0x1250 kthread+0x2ed/0x3a0 ret_from_fork+0x22/0x30 The buggy address belongs to the object at ffff88800d768e80 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 128 bytes inside of 168-byte region [ffff88800d768e80, ffff88800d768f28) The buggy address belongs to the physical page: page:0000000076b736b5 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xd768 flags: 0x100000000000200(slab|node=0|zone=1) raw: 0100000000000200 0000000000000000 dead000000000122 ffff8880080718c0 raw: 0000000000000000 0000000000110011 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88800d768e00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff88800d768e80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88800d768f00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ^ ffff88800d768f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800d769000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== loop1: detected capacity change from 0 to 40 FAT-fs (loop1): Directory bread(block 24) failed FAT-fs (loop1): Directory bread(block 25) failed FAT-fs (loop1): Directory bread(block 26) failed FAT-fs (loop1): Directory bread(block 27) failed FAT-fs (loop1): Directory bread(block 28) failed FAT-fs (loop1): Directory bread(block 29) failed FAT-fs (loop1): Directory bread(block 30) failed FAT-fs (loop1): Directory bread(block 31) failed FAT-fs (loop1): Directory bread(block 32) failed FAT-fs (loop1): Directory bread(block 33) failed random: crng reseeded on system resumption Restarting kernel threads ... done. EXT4-fs (loop7): mounted filesystem without journal. Quota mode: writeback. raw_sendmsg: syz-executor.6 forgot to set AF_INET. Fix it! syz-executor.6 (4012) used greatest stack depth: 24472 bytes left BUG: unable to handle page fault for address: ffffebde2f6e8188 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 1 PID: 84 Comm: kworker/1:3 Tainted: G B W 5.19.0-rc4-next-20220701 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Workqueue: events_freezable_power_ disk_events_workfn RIP: 0010:qlist_free_all+0xaf/0x190 Code: 80 4c 01 c2 0f 82 f0 00 00 00 48 c7 c0 00 00 00 80 48 2b 05 53 36 7c 03 48 01 d0 48 c1 e8 0c 48 c1 e0 06 48 03 05 31 36 7c 03 <48> 8b 48 08 48 89 c2 f6 c1 01 0f 85 b6 00 00 00 0f 1f 44 00 00 48 RSP: 0018:ffff88800f95f9a8 EFLAGS: 00010282 RAX: ffffebde2f6e8180 RBX: 0000000bdba0663b RCX: 1ffffffff0b1d44d RDX: 0000000c5ba0663b RSI: 0000000000000008 RDI: ffffffff81764e81 RBP: 0000000000000000 R08: 0000000bdba0663b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000 R13: ffff88800f95f9e8 R14: 0000000000000000 R15: ffff88800c459660 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffebde2f6e8188 CR3: 000000000edba000 CR4: 0000000000350ee0 Call Trace: kasan_quarantine_reduce+0x180/0x200 __kasan_slab_alloc+0x78/0x80 __kmalloc+0x1be/0x440 bio_kmalloc+0x3a/0x60 blk_rq_map_kern+0x49d/0x920 __scsi_execute+0x4a3/0x5d0 sr_check_events+0x17a/0xa30 cdrom_check_events+0x64/0x110 sr_block_check_events+0xbf/0xf0 disk_check_events+0xc7/0x420 process_one_work+0xa0f/0x1690 worker_thread+0x637/0x1250 kthread+0x2ed/0x3a0 ret_from_fork+0x22/0x30 Modules linked in: CR2: ffffebde2f6e8188 ---[ end trace 0000000000000000 ]--- RIP: 0010:qlist_free_all+0xaf/0x190 Code: 80 4c 01 c2 0f 82 f0 00 00 00 48 c7 c0 00 00 00 80 48 2b 05 53 36 7c 03 48 01 d0 48 c1 e8 0c 48 c1 e0 06 48 03 05 31 36 7c 03 <48> 8b 48 08 48 89 c2 f6 c1 01 0f 85 b6 00 00 00 0f 1f 44 00 00 48 RSP: 0018:ffff88800f95f9a8 EFLAGS: 00010282 RAX: ffffebde2f6e8180 RBX: 0000000bdba0663b RCX: 1ffffffff0b1d44d RDX: 0000000c5ba0663b RSI: 0000000000000008 RDI: ffffffff81764e81 RBP: 0000000000000000 R08: 0000000bdba0663b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000 R13: ffff88800f95f9e8 R14: 0000000000000000 R15: ffff88800c459660 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffebde2f6e8188 CR3: 000000000edba000 CR4: 0000000000350ee0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 4c 01 c2 add %r8,%rdx 3: 0f 82 f0 00 00 00 jb 0xf9 9: 48 c7 c0 00 00 00 80 mov $0xffffffff80000000,%rax 10: 48 2b 05 53 36 7c 03 sub 0x37c3653(%rip),%rax # 0x37c366a 17: 48 01 d0 add %rdx,%rax 1a: 48 c1 e8 0c shr $0xc,%rax 1e: 48 c1 e0 06 shl $0x6,%rax 22: 48 03 05 31 36 7c 03 add 0x37c3631(%rip),%rax # 0x37c365a * 29: 48 8b 48 08 mov 0x8(%rax),%rcx <-- trapping instruction 2d: 48 89 c2 mov %rax,%rdx 30: f6 c1 01 test $0x1,%cl 33: 0f 85 b6 00 00 00 jne 0xef 39: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 3e: 48 rex.W