================================================================== BUG: KASAN: slab-use-after-free in __do_sys_io_cancel fs/aio.c:2207 [inline] BUG: KASAN: slab-use-after-free in __se_sys_io_cancel+0x2c7/0x2d0 fs/aio.c:2174 Read of size 4 at addr ffff88801f6d47a0 by task syz-executor.1/27937 CPU: 0 PID: 27937 Comm: syz-executor.1 Not tainted 6.8.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x167/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x180 mm/kasan/report.c:601 __do_sys_io_cancel fs/aio.c:2207 [inline] __se_sys_io_cancel+0x2c7/0x2d0 fs/aio.c:2174 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 RIP: 0023:0xf7257579 Code: 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 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5e515ac EFLAGS: 00000206 ORIG_RAX: 00000000000000f9 RAX: ffffffffffffffda RBX: 00000000f73b8000 RCX: 0000000020000300 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 27937: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc+0x16f/0x340 mm/slub.c:3867 aio_get_req fs/aio.c:1060 [inline] io_submit_one+0x154/0x18b0 fs/aio.c:2050 __do_compat_sys_io_submit fs/aio.c:2155 [inline] __se_compat_sys_io_submit+0x197/0x320 fs/aio.c:2125 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 Freed by task 21332: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kmem_cache_free+0x102/0x2a0 mm/slub.c:4363 aio_poll_complete_work+0x467/0x670 fs/aio.c:1767 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:551 insert_work+0x3e/0x330 kernel/workqueue.c:1653 __queue_work+0xbf4/0x1000 kernel/workqueue.c:1802 queue_work_on+0x14f/0x250 kernel/workqueue.c:1837 queue_work include/linux/workqueue.h:548 [inline] schedule_work include/linux/workqueue.h:609 [inline] aio_poll_cancel+0xbb/0x130 fs/aio.c:1779 __do_sys_io_cancel fs/aio.c:2196 [inline] __se_sys_io_cancel+0x126/0x2d0 fs/aio.c:2174 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 The buggy address belongs to the object at ffff88801f6d4780 which belongs to the cache aio_kiocb of size 216 The buggy address is located 32 bytes inside of freed 216-byte region [ffff88801f6d4780, ffff88801f6d4858) The buggy address belongs to the physical page: page:ffffea00007db500 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801f6d4640 pfn:0x1f6d4 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff88801a6d7dc0 dead000000000122 0000000000000000 raw: ffff88801f6d4640 00000000800c000a 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5782, tgid 5780 (syz-executor.3), ts 176587813570, free_ts 176586454688 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc+0x24d/0x340 mm/slub.c:3867 aio_get_req fs/aio.c:1060 [inline] io_submit_one+0x154/0x18b0 fs/aio.c:2050 __do_compat_sys_io_submit fs/aio.c:2155 [inline] __se_compat_sys_io_submit+0x197/0x320 fs/aio.c:2125 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbd/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 page last free pid 5784 tgid 5781 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 tlb_batch_list_free mm/mmu_gather.c:114 [inline] tlb_finish_mmu+0x11f/0x200 mm/mmu_gather.c:395 exit_mmap+0x4b6/0xd40 mm/mmap.c:3292 __mmput+0x115/0x3c0 kernel/fork.c:1343 exit_mm+0x21f/0x310 kernel/exit.c:569 do_exit+0x9af/0x2740 kernel/exit.c:858 do_group_exit+0x206/0x2c0 kernel/exit.c:1020 get_signal+0x176d/0x1850 kernel/signal.c:2893 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc8/0x360 kernel/entry/common.c:212 __do_fast_syscall_32+0xcf/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 Memory state around the buggy address: ffff88801f6d4680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801f6d4700: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801f6d4780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801f6d4800: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff88801f6d4880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop