================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:564 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x173/0xee0 kernel/locking/mutex.c:735 Read of size 8 at addr ffff88806a02c130 by task jffs2_gcd_mtd0/6193 CPU: 0 UID: 0 PID: 6193 Comm: jffs2_gcd_mtd0 Not tainted 6.13.0-syzkaller-g3d3a9c8b89d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __mutex_lock_common kernel/locking/mutex.c:564 [inline] __mutex_lock+0x173/0xee0 kernel/locking/mutex.c:735 jffs2_garbage_collect_pass+0xae/0x2120 fs/jffs2/gc.c:134 jffs2_garbage_collect_thread+0x64b/0x6e0 fs/jffs2/background.c:155 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 6188: 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:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] jffs2_init_fs_context+0x4f/0xc0 fs/jffs2/super.c:314 alloc_fs_context+0x68a/0x800 fs/fs_context.c:318 do_new_mount+0x160/0xb40 fs/namespace.c:3539 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088 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 6122: 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:582 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:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4613 [inline] kfree+0x196/0x430 mm/slub.c:4761 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413 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:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806a02c000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 304 bytes inside of freed 4096-byte region [ffff88806a02c000, ffff88806a02d000) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6a028 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 head: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea0001a80a01 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 6188, tgid 6187 (syz-executor.0), ts 84309834889, free_ts 18085947765 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x3e1/0x780 mm/mempolicy.c:2269 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x5a/0x2b0 mm/slub.c:2589 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_noprof+0x2e6/0x4c0 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x258/0x4f0 security/tomoyo/file.c:771 security_file_open+0xac/0x250 security/security.c:3105 do_dentry_open+0x328/0x1b70 fs/open.c:921 vfs_open+0x3e/0x330 fs/open.c:1068 do_open fs/namei.c:3828 [inline] path_openat+0x2c84/0x3590 fs/namei.c:3987 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xd2c/0x1000 mm/page_alloc.c:2659 free_contig_range+0x14c/0x430 mm/page_alloc.c:6635 destroy_args+0x92/0x910 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x248/0x870 init/main.c:1266 do_initcall_level+0x157/0x210 init/main.c:1328 do_initcalls+0x3f/0x80 init/main.c:1344 kernel_init_freeable+0x435/0x5d0 init/main.c:1577 kernel_init+0x1d/0x2b0 init/main.c:1466 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff88806a02c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806a02c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806a02c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806a02c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806a02c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================