kobject_add_internal failed for syz:syz with -EEXIST, don't try to register things with the same name in the same directory. gfs2: fsid=syz:syz: error -17 adding sysfs files ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic_dec include/linux/atomic/atomic-instrumented.h:244 [inline] BUG: KASAN: use-after-free in gfs2_qd_dispose fs/gfs2/quota.c:137 [inline] BUG: KASAN: use-after-free in gfs2_qd_shrink_scan+0x584/0x7e4 fs/gfs2/quota.c:175 Write of size 4 at addr ffff0000ecf0ca70 by task syz-executor.0/7252 CPU: 1 PID: 7252 Comm: syz-executor.0 Not tainted 5.15.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x174/0x1e4 mm/kasan/report.c:451 kasan_check_range+0x274/0x2b4 mm/kasan/generic.c:189 __kasan_check_write+0x44/0x54 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:244 [inline] gfs2_qd_dispose fs/gfs2/quota.c:137 [inline] gfs2_qd_shrink_scan+0x584/0x7e4 fs/gfs2/quota.c:175 do_shrink_slab+0x4b4/0x10b0 mm/vmscan.c:758 shrink_slab+0x1f8/0x894 mm/vmscan.c:918 drop_slab_node+0xcc/0x170 mm/vmscan.c:953 drop_slab+0x98/0x140 mm/vmscan.c:963 drop_caches_sysctl_handler+0x178/0x394 fs/drop_caches.c:66 proc_sys_call_handler+0x4cc/0x7cc fs/proc/proc_sysctl.c:587 proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:613 do_iter_readv_writev+0x420/0x5f8 do_iter_write+0x1b8/0x664 fs/read_write.c:855 vfs_iter_write+0x88/0xac fs/read_write.c:896 iter_file_splice_write+0x618/0xc48 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0xe4/0x1c0 fs/splice.c:936 splice_direct_to_actor+0x408/0x9a0 fs/splice.c:891 do_splice_direct+0x1f4/0x334 fs/splice.c:979 do_sendfile+0x4bc/0xc70 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1311 [inline] __se_sys_sendfile64 fs/read_write.c:1303 [inline] __arm64_sys_sendfile64+0x264/0x408 fs/read_write.c:1303 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 6722: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xbc/0xfc mm/kasan/common.c:513 __kasan_kmalloc+0x10/0x1c mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x27c/0x47c mm/slub.c:3247 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] init_sbd fs/gfs2/ops_fstype.c:77 [inline] gfs2_fill_super+0x140/0x2010 fs/gfs2/ops_fstype.c:1151 get_tree_bdev+0x360/0x54c fs/super.c:1312 gfs2_get_tree+0x54/0x1b4 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x90/0x274 fs/super.c:1517 do_new_mount+0x278/0x8fc fs/namespace.c:3005 path_mount+0x594/0x101c fs/namespace.c:3335 do_mount fs/namespace.c:3348 [inline] __do_sys_mount fs/namespace.c:3556 [inline] __se_sys_mount fs/namespace.c:3533 [inline] __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3533 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 4917: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1ec mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x178/0x410 mm/slub.c:4559 free_sbd+0x5c/0x6c fs/gfs2/ops_fstype.c:69 gfs2_put_super+0x60c/0x684 fs/gfs2/super.c:632 generic_shutdown_super+0x130/0x29c fs/super.c:475 kill_block_super+0x70/0xdc fs/super.c:1414 gfs2_kill_sb+0xc0/0xd4 deactivate_locked_super+0xb8/0x13c fs/super.c:335 deactivate_super+0x108/0x128 fs/super.c:366 cleanup_mnt+0x3c0/0x474 fs/namespace.c:1143 __cleanup_mnt+0x20/0x30 fs/namespace.c:1150 task_work_run+0x130/0x1e4 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff0000ecf0c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2672 bytes inside of 8192-byte region [ffff0000ecf0c000, ffff0000ecf0e000) The buggy address belongs to the page: page:000000001620ac8f refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12cf08 head:000000001620ac8f order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc0003697000 0000000200000002 ffff0000c0002c00 raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000ecf0c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000ecf0c980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000ecf0ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000ecf0ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000ecf0cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== syz-executor.0 (7252): drop_caches: 2