================================================================== BUG: KASAN: slab-use-after-free in __ref_is_percpu include/linux/percpu-refcount.h:174 [inline] BUG: KASAN: slab-use-after-free in percpu_ref_put_many include/linux/percpu-refcount.h:332 [inline] BUG: KASAN: slab-use-after-free in percpu_ref_put+0xda/0x250 include/linux/percpu-refcount.h:351 Read of size 8 at addr ffff88803812e0b0 by task kworker/u4:8/1084 CPU: 0 UID: 0 PID: 1084 Comm: kworker/u4:8 Not tainted 6.12.0-syzkaller-00971-g158f238aa69d #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: loop0 loop_rootcg_workfn Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __ref_is_percpu include/linux/percpu-refcount.h:174 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:332 [inline] percpu_ref_put+0xda/0x250 include/linux/percpu-refcount.h:351 blk_update_request+0x5e5/0x1160 block/blk-mq.c:981 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1143 loop_handle_cmd drivers/block/loop.c:1926 [inline] loop_process_work+0x1bc8/0x21c0 drivers/block/loop.c:1944 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5322: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] __bch2_dev_alloc+0x57/0xa60 fs/bcachefs/super.c:1304 bch2_dev_alloc+0xd4/0x170 fs/bcachefs/super.c:1374 bch2_fs_alloc fs/bcachefs/super.c:939 [inline] bch2_fs_open+0x2e3f/0x2f80 fs/bcachefs/super.c:2065 bch2_fs_get_tree+0x738/0x1710 fs/bcachefs/fs.c:2157 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5322: 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:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x1a0/0x440 mm/slub.c:4727 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22f/0x480 lib/kobject.c:737 bch2_fs_free+0x27b/0x3c0 fs/bcachefs/super.c:667 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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:541 insert_work+0x3e/0x330 kernel/workqueue.c:2183 __queue_work+0xc8b/0xf50 kernel/workqueue.c:2339 queue_work_on+0x1c2/0x380 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:662 [inline] bch2_dev_do_discards+0x17a/0x1f0 fs/bcachefs/alloc_background.c:1912 bch2_do_discards+0x29/0x60 fs/bcachefs/alloc_background.c:1923 journal_write_done+0x785/0xea0 fs/bcachefs/journal_io.c:1625 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Second to 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:541 insert_work+0x3e/0x330 kernel/workqueue.c:2183 __queue_work+0xc8b/0xf50 kernel/workqueue.c:2339 queue_work_on+0x1c2/0x380 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:662 [inline] bch2_dev_do_discards+0x17a/0x1f0 fs/bcachefs/alloc_background.c:1912 bch2_do_discards+0x29/0x60 fs/bcachefs/alloc_background.c:1923 journal_write_done+0x785/0xea0 fs/bcachefs/journal_io.c:1625 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88803812e000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 176 bytes inside of freed 4096-byte region [ffff88803812e000, ffff88803812f000) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x38128 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 head: 04fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 head: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 head: 04fff00000000003 ffffea0000e04a01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5301, tgid 5301 (udevd), ts 59253905428, free_ts 59018485432 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3649/0x3790 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x140 mm/slub.c:2412 allocate_slab+0x5a/0x2f0 mm/slub.c:2578 new_slab mm/slub.c:2631 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818 __slab_alloc+0x58/0xa0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x25a/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path2_perm+0x3eb/0xbb0 security/tomoyo/file.c:923 tomoyo_path_rename+0x198/0x1e0 security/tomoyo/tomoyo.c:300 security_path_rename+0x266/0x4e0 security/security.c:2022 do_renameat2+0x94a/0x13f0 fs/namei.c:5211 __do_sys_rename fs/namei.c:5271 [inline] __se_sys_rename fs/namei.c:5269 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:5269 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 page last free pid 5324 tgid 5324 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657 __slab_free+0x31b/0x3d0 mm/slub.c:4490 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] load_elf_phdrs fs/binfmt_elf.c:532 [inline] load_elf_binary+0x2eb/0x2710 fs/binfmt_elf.c:861 search_binary_handler fs/exec.c:1752 [inline] exec_binprm fs/exec.c:1794 [inline] bprm_execve+0xaf8/0x1770 fs/exec.c:1845 do_execveat_common+0x55f/0x6f0 fs/exec.c:1952 do_execve fs/exec.c:2026 [inline] __do_sys_execve fs/exec.c:2102 [inline] __se_sys_execve fs/exec.c:2097 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2097 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88803812df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803812e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803812e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803812e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803812e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================