================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:72 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline] BUG: KASAN: use-after-free in __refcount_add_not_zero include/linux/refcount.h:152 [inline] BUG: KASAN: use-after-free in __refcount_inc_not_zero include/linux/refcount.h:227 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero include/linux/refcount.h:245 [inline] BUG: KASAN: use-after-free in io_worker_get io_uring/io-wq.c:153 [inline] BUG: KASAN: use-after-free in io_wq_for_each_worker io_uring/io-wq.c:846 [inline] BUG: KASAN: use-after-free in io_wq_exit_workers io_uring/io-wq.c:1250 [inline] BUG: KASAN: use-after-free in io_wq_put_and_exit+0x584/0xe30 io_uring/io-wq.c:1289 Read of size 4 at addr ffff88801f391000 by task syz-executor.0/10247 CPU: 2 PID: 10247 Comm: syz-executor.0 Not tainted 6.2.0-rc2-syzkaller-00256-ga689b938df39 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x45d mm/kasan/report.c:417 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x141/0x190 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] refcount_read include/linux/refcount.h:147 [inline] __refcount_add_not_zero include/linux/refcount.h:152 [inline] __refcount_inc_not_zero include/linux/refcount.h:227 [inline] refcount_inc_not_zero include/linux/refcount.h:245 [inline] io_worker_get io_uring/io-wq.c:153 [inline] io_wq_for_each_worker io_uring/io-wq.c:846 [inline] io_wq_exit_workers io_uring/io-wq.c:1250 [inline] io_wq_put_and_exit+0x584/0xe30 io_uring/io-wq.c:1289 io_uring_clean_tctx+0x117/0x178 io_uring/tctx.c:193 io_uring_cancel_generic+0x5ae/0x606 io_uring/io_uring.c:3145 io_uring_files_cancel include/linux/io_uring.h:55 [inline] do_exit+0x522/0x2950 kernel/exit.c:822 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 get_signal+0x21c3/0x2450 kernel/signal.c:2859 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_int80_syscall_32+0x57/0x90 arch/x86/entry/common.c:135 entry_INT80_compat+0x8f/0xa0 arch/x86/entry/entry_64_compat.S:353 RIP: 0023:0xf7f07547 Code: 10 03 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 80 5d 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 RSP: 002b:00000000f7f025cc EFLAGS: 00000296 ORIG_RAX: 000000000000005c RAX: 000000000000005c RBX: 0000000020000040 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10247: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa5/0xb0 mm/kasan/common.c:380 kmalloc_node include/linux/slab.h:606 [inline] kzalloc_node include/linux/slab.h:731 [inline] create_io_worker+0x10c/0x630 io_uring/io-wq.c:801 io_wqe_create_worker io_uring/io-wq.c:310 [inline] io_wqe_enqueue+0x6c3/0xbc0 io_uring/io-wq.c:936 io_queue_iowq+0x282/0x5c0 io_uring/io_uring.c:475 io_queue_async+0x1e9/0x5b0 io_uring/io_uring.c:2013 io_queue_sqe io_uring/io_uring.c:2037 [inline] io_req_task_submit+0x1c4/0x220 io_uring/io_uring.c:1369 handle_tw_list+0xa8/0x420 io_uring/io_uring.c:1147 tctx_task_work+0x12e/0x520 io_uring/io_uring.c:1202 task_work_run+0x16f/0x270 kernel/task_work.c:179 get_signal+0x1c7/0x2450 kernel/signal.c:2635 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_int80_syscall_32+0x57/0x90 arch/x86/entry/common.c:135 entry_INT80_compat+0x8f/0xa0 arch/x86/entry/entry_64_compat.S:353 Freed by task 10247: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xaf/0x3b0 mm/slub.c:3800 io_wq_cancel_tw_create io_uring/io-wq.c:1233 [inline] io_wq_exit_workers io_uring/io-wq.c:1244 [inline] io_wq_put_and_exit+0x120/0xe30 io_uring/io-wq.c:1289 io_uring_clean_tctx+0x117/0x178 io_uring/tctx.c:193 io_uring_cancel_generic+0x5ae/0x606 io_uring/io_uring.c:3145 io_uring_files_cancel include/linux/io_uring.h:55 [inline] do_exit+0x522/0x2950 kernel/exit.c:822 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 get_signal+0x21c3/0x2450 kernel/signal.c:2859 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_int80_syscall_32+0x57/0x90 arch/x86/entry/common.c:135 entry_INT80_compat+0x8f/0xa0 arch/x86/entry/entry_64_compat.S:353 Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488 task_work_add+0x7f/0x2c0 kernel/task_work.c:48 io_queue_worker_create+0x41d/0x660 io_uring/io-wq.c:373 io_wqe_dec_running+0x1e4/0x240 io_uring/io-wq.c:410 io_wq_worker_sleeping+0xa6/0xc0 io_uring/io-wq.c:698 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x16e/0x1b0 kernel/sched/core.c:6628 do_signal_stop+0x54c/0x6d0 kernel/signal.c:2477 get_signal+0xd38/0x2450 kernel/signal.c:2706 io_wqe_worker+0x632/0xe40 io_uring/io-wq.c:651 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488 task_work_add+0x7f/0x2c0 kernel/task_work.c:48 io_queue_worker_create+0x41d/0x660 io_uring/io-wq.c:373 io_wqe_dec_running+0x1e4/0x240 io_uring/io-wq.c:410 io_wq_worker_sleeping+0xa6/0xc0 io_uring/io-wq.c:698 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x16e/0x1b0 kernel/sched/core.c:6628 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167 io_wqe_worker+0x5d0/0xe40 io_uring/io-wq.c:647 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff88801f391000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff88801f391000, ffff88801f391200) The buggy address belongs to the physical page: page:ffffea00007ce400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f390 head:ffffea00007ce400 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012442c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1828, tgid 1828 (kworker/u17:2), ts 24277445745, free_ts 0 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2286 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x1a4/0x430 mm/slub.c:3491 kmalloc_trace+0x26/0x60 mm/slab_common.c:1062 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_bprm+0x51/0x900 fs/exec.c:1510 kernel_execve+0xaf/0x500 fs/exec.c:1981 call_usermodehelper_exec_async+0x2e7/0x580 kernel/umh.c:113 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 page_owner free stack trace missing Memory state around the buggy address: ffff88801f390f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801f390f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801f391000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801f391080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801f391100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 10 03 adc %al,(%rbx) 2: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 6: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740f c: 10 06 adc %al,(%rsi) e: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 12: 10 07 adc %al,(%rdi) 14: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 18: 10 08 adc %cl,(%rax) 1a: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 00 add %al,(%rax) 20: 00 00 add %al,(%rax) 22: 00 51 52 add %dl,0x52(%rcx) 25: 55 push %rbp 26: 89 e5 mov %esp,%ebp 28: 0f 34 sysenter * 2a: cd 80 int $0x80 <-- trapping instruction 2c: 5d pop %rbp 2d: 5a pop %rdx 2e: 59 pop %rcx 2f: c3 retq 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 3b: 8d .byte 0x8d 3c: b4 26 mov $0x26,%ah