================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 Read of size 8 at addr ffff88807c06c130 by task jffs2_gcd_mtd0/12429 CPU: 1 PID: 12429 Comm: jffs2_gcd_mtd0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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 __mutex_lock_common kernel/locking/mutex.c:587 [inline] __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 jffs2_garbage_collect_pass+0xae/0x2120 fs/jffs2/gc.c:134 jffs2_garbage_collect_thread+0x651/0x6e0 fs/jffs2/background.c:155 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Allocated by task 12426: 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:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x1db/0x360 mm/slub.c:3997 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] jffs2_init_fs_context+0x4f/0xc0 fs/jffs2/super.c:313 alloc_fs_context+0x68a/0x800 fs/fs_context.c:318 do_new_mount+0x160/0xb40 fs/namespace.c:3331 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Freed by task 11603: 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+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:2106 [inline] slab_free mm/slub.c:4280 [inline] kfree+0x14a/0x380 mm/slub.c:4390 deactivate_locked_super+0xc4/0x130 fs/super.c:472 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24f/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [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+0x168/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 The buggy address belongs to the object at ffff88807c06c000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 304 bytes inside of freed 4096-byte region [ffff88807c06c000, ffff88807c06d000) The buggy address belongs to the physical page: page:ffffea0001f01a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c068 head:ffffea0001f01a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888014c42140 ffffea00019da600 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffffff 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 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 8846, tgid 8846 (syz-executor.3), ts 422766299968, free_ts 422670760196 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+0x256/0x680 mm/page_alloc.c:4569 __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:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] __do_kmalloc_node mm/slub.c:3965 [inline] __kmalloc+0x2e5/0x4a0 mm/slub.c:3979 kmalloc include/linux/slab.h:632 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x23a/0x880 security/tomoyo/file.c:723 security_file_ioctl+0x75/0xb0 security/security.c:2758 __do_sys_ioctl fs/ioctl.c:898 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:890 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 page last free pid 10493 tgid 10493 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+0x95d/0xa80 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 discard_slab mm/slub.c:2437 [inline] __put_partials+0xeb/0x130 mm/slub.c:2906 put_cpu_partial+0x17c/0x250 mm/slub.c:2981 __slab_free+0x2ea/0x3d0 mm/slub.c:4151 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:378 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:3966 [inline] __kmalloc+0x233/0x4a0 mm/slub.c:3979 kmalloc include/linux/slab.h:632 [inline] kzalloc include/linux/slab.h:749 [inline] __register_sysctl_table+0x67/0x1440 fs/proc/proc_sysctl.c:1360 neigh_sysctl_register+0x416/0x500 net/core/neighbour.c:3859 addrconf_sysctl_register+0xb2/0x1c0 net/ipv6/addrconf.c:7258 ipv6_add_dev+0xcff/0x1220 net/ipv6/addrconf.c:455 addrconf_notify+0x6a7/0x1020 net/ipv6/addrconf.c:3650 notifier_call_chain+0x18f/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] register_netdevice+0x15b2/0x1a20 net/core/dev.c:10307 Memory state around the buggy address: ffff88807c06c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c06c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c06c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c06c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c06c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================