================================================================== BUG: KASAN: use-after-free in __add_wait_queue include/linux/wait.h:177 [inline] BUG: KASAN: use-after-free in add_wait_queue+0x1c0/0x260 kernel/sched/wait.c:24 Read of size 4 at addr ffff888019a15518 by task syz-executor.5/4330 CPU: 1 PID: 4330 Comm: syz-executor.5 Tainted: G W 5.17.0-syzkaller-01442-gb47d5a4f6b8d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 __add_wait_queue include/linux/wait.h:177 [inline] add_wait_queue+0x1c0/0x260 kernel/sched/wait.c:24 __io_queue_proc+0x18c/0x6f0 fs/io_uring.c:6131 poll_wait include/linux/poll.h:49 [inline] n_tty_poll+0x76/0x8a0 drivers/tty/n_tty.c:2322 tty_poll+0x139/0x1b0 drivers/tty/tty_io.c:2212 vfs_poll include/linux/poll.h:88 [inline] __io_arm_poll_handler+0x397/0xc00 fs/io_uring.c:6165 io_arm_poll_handler+0x42c/0x940 fs/io_uring.c:6257 io_queue_sqe_arm_apoll+0x6d/0x430 fs/io_uring.c:7499 __io_queue_sqe fs/io_uring.c:7541 [inline] io_queue_sqe fs/io_uring.c:7568 [inline] io_submit_sqe fs/io_uring.c:7776 [inline] io_submit_sqes+0x7dda/0x9310 fs/io_uring.c:7882 __do_sys_io_uring_enter+0x9f1/0x1520 fs/io_uring.c:10924 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf6e77549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f58715cc EFLAGS: 00000296 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000000002fb RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4310: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc include/linux/slab.h:581 [inline] io_arm_poll_handler+0x39d/0x940 fs/io_uring.c:6248 io_queue_sqe_arm_apoll+0x6d/0x430 fs/io_uring.c:7499 __io_queue_sqe fs/io_uring.c:7541 [inline] io_queue_sqe fs/io_uring.c:7568 [inline] io_submit_sqe fs/io_uring.c:7776 [inline] io_submit_sqes+0x7dda/0x9310 fs/io_uring.c:7882 __do_sys_io_uring_enter+0x9f1/0x1520 fs/io_uring.c:10924 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Freed by task 3702: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x126/0x160 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:215 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3509 [inline] kfree+0xd0/0x390 mm/slub.c:4562 io_flush_apoll_cache fs/io_uring.c:10038 [inline] io_ring_ctx_free fs/io_uring.c:10064 [inline] io_ring_exit_work+0x7f7/0x1053 fs/io_uring.c:10244 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3595 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1705 unregister_sysctl_table fs/proc/proc_sysctl.c:1743 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1718 ip_vs_control_net_cleanup_sysctl net/netfilter/ipvs/ip_vs_ctl.c:4132 [inline] ip_vs_control_net_cleanup+0x246/0x500 net/netfilter/ipvs/ip_vs_ctl.c:4218 __ip_vs_cleanup_batch+0x95/0x120 net/netfilter/ipvs/ip_vs_core.c:2356 ops_exit_list+0x125/0x170 net/core/net_namespace.c:173 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:597 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888019a15500 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 24 bytes inside of 96-byte region [ffff888019a15500, ffff888019a15560) The buggy address belongs to the page: page:ffffea0000668540 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x19a15 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001fd5b80 dead000000000004 ffff888010c41780 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 3684, ts 97453174001, free_ts 97444708019 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x27f/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0xbe1/0x12b0 mm/slub.c:3018 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc_trace+0x2f8/0x3d0 mm/slub.c:3255 kmalloc include/linux/slab.h:581 [inline] io_arm_poll_handler+0x39d/0x940 fs/io_uring.c:6248 io_queue_sqe_arm_apoll+0x6d/0x430 fs/io_uring.c:7499 __io_queue_sqe fs/io_uring.c:7541 [inline] io_queue_sqe fs/io_uring.c:7568 [inline] io_submit_sqe fs/io_uring.c:7776 [inline] io_submit_sqes+0x7dda/0x9310 fs/io_uring.c:7882 __do_sys_io_uring_enter+0x9f1/0x1520 fs/io_uring.c:10924 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 __vunmap+0x798/0xc50 mm/vmalloc.c:2635 free_work+0x58/0x70 mm/vmalloc.c:97 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888019a15400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888019a15480: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff888019a15500: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888019a15580: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff888019a15600: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi