Hello, syzbot found the following issue on: HEAD commit: c500bee1c5b2 Linux 5.14-rc4 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1415477a300000 kernel config: https://syzkaller.appspot.com/x/.config?x=343fd21f6f4da2d6 dashboard link: https://syzkaller.appspot.com/bug?extid=5fa698422954b6b9307b compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5fa698422954b6b9307b@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3210 [inline] BUG: KASAN: double-free or invalid-free in kfree+0xe4/0x530 mm/slub.c:4264 CPU: 1 PID: 813 Comm: syz-executor.2 Not tainted 5.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 kasan_report_invalid_free+0x51/0x80 mm/kasan/report.c:358 ____kasan_slab_free mm/kasan/common.c:346 [inline] __kasan_slab_free+0x120/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xe4/0x530 mm/slub.c:4264 bdev_free_inode+0xe0/0x110 fs/block_dev.c:816 i_callback+0x3f/0x70 fs/inode.c:222 rcu_do_batch kernel/rcu/tree.c:2550 [inline] rcu_core+0x7ab/0x1380 kernel/rcu/tree.c:2785 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 </IRQ> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:check_kcov_mode+0x2c/0x40 kernel/kcov.c:174 Code: 05 a9 5c 8c 7e 89 c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b 96 34 15 00 00 85 d2 74 0b 8b 86 10 15 00 00 <39> f8 0f 94 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 31 c0 RSP: 0018:ffffc9000941f590 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000009 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88801b691c40 RDI: 0000000000000003 RBP: ffff888036020580 R08: 0000000000000000 R09: 0000000000000009 R10: ffffffff839f2957 R11: 0000000000000010 R12: 0000000000000010 R13: 00000000000003af R14: dffffc0000000000 R15: 0000000000000000 write_comp_data kernel/kcov.c:218 [inline] __sanitizer_cov_trace_const_cmp4+0x1c/0x70 kernel/kcov.c:284 tomoyo_domain_quota_is_ok+0x307/0x550 security/tomoyo/util.c:1093 tomoyo_supervisor+0x2f2/0xf00 security/tomoyo/common.c:2089 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline] tomoyo_path_permission security/tomoyo/file.c:587 [inline] tomoyo_path_permission+0x270/0x3a0 security/tomoyo/file.c:573 tomoyo_check_open_permission+0x33e/0x380 security/tomoyo/file.c:777 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:306 security_file_open+0x52/0x4f0 security/security.c:1633 do_dentry_open+0x353/0x11d0 fs/open.c:813 do_open fs/namei.c:3374 [inline] path_openat+0x1c23/0x27f0 fs/namei.c:3507 do_filp_open+0x1aa/0x400 fs/namei.c:3534 do_sys_openat2+0x16d/0x420 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_openat fs/open.c:1236 [inline] __se_sys_openat fs/open.c:1231 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4196d4 Code: 84 00 00 00 00 00 44 89 54 24 0c e8 96 f9 ff ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 89 44 24 0c e8 c8 f9 ff ff 8b 44 RSP: 002b:00007f69595e9060 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004196d4 RDX: 0000000000000002 RSI: 00007f69595e90f0 RDI: 00000000ffffff9c RBP: 00007f69595e90f0 R08: 0000000000000000 R09: 00007f69595e8f70 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000a9fb1f R14: 00007f69595e9300 R15: 0000000000022000 Allocated by task 802: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522 kmalloc_node include/linux/slab.h:609 [inline] kzalloc_node include/linux/slab.h:732 [inline] __alloc_disk_node+0x4e/0x380 block/genhd.c:1246 __blk_mq_alloc_disk+0xec/0x190 block/blk-mq.c:3145 loop_add+0x324/0x8c0 drivers/block/loop.c:2345 loop_control_ioctl+0x130/0x450 drivers/block/loop.c:2492 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 802: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xe4/0x530 mm/slub.c:4264 __alloc_disk_node+0x2e8/0x380 block/genhd.c:1271 __blk_mq_alloc_disk+0xec/0x190 block/blk-mq.c:3145 loop_add+0x324/0x8c0 drivers/block/loop.c:2345 loop_control_ioctl+0x130/0x450 drivers/block/loop.c:2492 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3029 [inline] call_rcu+0xb1/0x750 kernel/rcu/tree.c:3109 put_ctx kernel/events/core.c:1273 [inline] put_ctx+0x116/0x1e0 kernel/events/core.c:1266 perf_event_exit_task_context kernel/events/core.c:12664 [inline] perf_event_exit_task+0x528/0x740 kernel/events/core.c:12693 do_exit+0xbe4/0x2a60 kernel/exit.c:834 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2808 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1332 __queue_work+0x5c1/0xed0 kernel/workqueue.c:1498 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1419 expire_timers kernel/time/timer.c:1459 [inline] __run_timers.part.0+0x49f/0xa50 kernel/time/timer.c:1732 __run_timers kernel/time/timer.c:1713 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1745 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 The buggy address belongs to the object at ffff88802ac59400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff88802ac59400, ffff88802ac59600) The buggy address belongs to the page: page:ffffea0000ab1600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2ac58 head:ffffea0000ab1600 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010841c80 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 1, ts 18483051698, free_ts 0 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4169 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244 alloc_slab_page mm/slub.c:1688 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1828 new_slab mm/slub.c:1891 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2800 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] kmem_cache_alloc_trace+0x30f/0x3c0 mm/slub.c:2981 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] devcgroup_css_alloc+0x3d/0x120 security/device_cgroup.c:214 css_create kernel/cgroup/cgroup.c:5229 [inline] cgroup_apply_control_enable+0x4b8/0xc00 kernel/cgroup/cgroup.c:3085 cgroup_mkdir+0x5ac/0x10f0 kernel/cgroup/cgroup.c:5447 kernfs_iop_mkdir+0x146/0x1d0 fs/kernfs/dir.c:1127 vfs_mkdir+0x52e/0x760 fs/namei.c:3823 do_mkdirat+0x284/0x310 fs/namei.c:3848 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page_owner free stack trace missing Memory state around the buggy address: ffff88802ac59300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802ac59380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802ac59400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802ac59480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ac59500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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