================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common+0x100/0x21a0 kernel/locking/mutex.c:587 Read of size 8 at addr ffff0000db498130 by task jffs2_gcd_mtd0/6695 CPU: 1 PID: 6695 Comm: jffs2_gcd_mtd0 Not tainted 6.10.0-rc7-syzkaller-00109-gc912bf709078 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x198/0x538 mm/kasan/report.c:488 kasan_report+0xd8/0x138 mm/kasan/report.c:601 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __mutex_lock_common+0x100/0x21a0 kernel/locking/mutex.c:587 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_interruptible_nested+0x2c/0x38 kernel/locking/mutex.c:826 jffs2_garbage_collect_pass+0xa4/0x1a50 fs/jffs2/gc.c:134 jffs2_garbage_collect_thread+0x414/0x48c fs/jffs2/background.c:155 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 Allocated by task 6692: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace_noprof+0x244/0x374 mm/slub.c:4154 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] jffs2_init_fs_context+0x58/0xc8 fs/jffs2/super.c:314 alloc_fs_context+0x514/0x7a4 fs/fs_context.c:318 fs_context_for_mount+0x34/0x44 fs/fs_context.c:332 do_new_mount+0x14c/0x900 fs/namespace.c:3331 path_mount+0x590/0xe04 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __arm64_sys_mount+0x3c4/0x488 fs/namespace.c:3875 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:131 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:150 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 Freed by task 6579: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:579 poison_slab_object+0x128/0x180 mm/kasan/common.c:240 __kasan_slab_free+0x3c/0x70 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4438 [inline] kfree+0x154/0x3e0 mm/slub.c:4559 jffs2_kill_sb+0x9c/0xb0 fs/jffs2/super.c:351 deactivate_locked_super+0xc4/0x12c fs/super.c:473 deactivate_super+0xe0/0x100 fs/super.c:506 cleanup_mnt+0x34c/0x3dc fs/namespace.c:1267 __cleanup_mnt+0x20/0x30 fs/namespace.c:1274 task_work_run+0x230/0x2e0 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] do_notify_resume+0x178/0x1f4 arch/arm64/kernel/entry-common.c:151 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:713 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The buggy address belongs to the object at ffff0000db498000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 304 bytes inside of freed 4096-byte region [ffff0000db498000, ffff0000db499000) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11b498 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 05ffc00000000040 ffff0000c0002140 fffffdffc36d3400 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000 head: 05ffc00000000040 ffff0000c0002140 fffffdffc36d3400 dead000000000002 head: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000 head: 05ffc00000000003 fffffdffc36d2601 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000db498000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000db498080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000db498100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000db498180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000db498200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== jffs2: Erase at 0x0001e000 failed immediately: errno -524 jffs2: Erase at 0x0001d000 failed immediately: errno -524 jffs2: Erase at 0x0001c000 failed immediately: errno -524 jffs2: Erase at 0x0001b000 failed immediately: errno -524 jffs2: Erase at 0x0001a000 failed immediately: errno -524 jffs2: Erase at 0x00019000 failed immediately: errno -524 jffs2: Erase at 0x00018000 failed immediately: errno -524 jffs2: Erase at 0x00017000 failed immediately: errno -524 jffs2: Erase at 0x00016000 failed immediately: errno -524 jffs2: Erase at 0x00015000 failed immediately: errno -524 jffs2: Erase at 0x00014000 failed immediately: errno -524 jffs2: Erase at 0x00013000 failed immediately: errno -524 jffs2: Erase at 0x00012000 failed immediately: errno -524 jffs2: Erase at 0x00011000 failed immediately: errno -524 jffs2: Erase at 0x00010000 failed immediately: errno -524 jffs2: Erase at 0x0000f000 failed immediately: errno -524 jffs2: Erase at 0x0000e000 failed immediately: errno -524 jffs2: Erase at 0x0000d000 failed immediately: errno -524 jffs2: Erase at 0x0000c000 failed immediately: errno -524 jffs2: Erase at 0x0000b000 failed immediately: errno -524 jffs2: Erase at 0x0000a000 failed immediately: errno -524 jffs2: Erase at 0x00009000 failed immediately: errno -524 jffs2: Erase at 0x00008000 failed immediately: errno -524 jffs2: Erase at 0x00007000 failed immediately: errno -524 jffs2: Erase at 0x00006000 failed immediately: errno -524 jffs2: Erase at 0x00005000 failed immediately: errno -524 jffs2: Erase at 0x00004000 failed immediately: errno -524 jffs2: Erase at 0x00003000 failed immediately: errno -524 jffs2: Erase at 0x00002000 failed immediately: errno -524 list_del corruption. next->prev should be ffff0000db4d0048, but was 048403bf000019b3. (next=ffff0000db4d0000) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:67!