================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1375 [inline] BUG: KASAN: slab-use-after-free in gfs2_qd_dealloc+0x81/0xe0 fs/gfs2/quota.c:112 Write of size 4 at addr ffff88807c6e8a78 by task udevd/5159 CPU: 0 PID: 5159 Comm: udevd Not tainted 6.6.101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x288/0x290 mm/kasan/generic.c:187 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1375 [inline] gfs2_qd_dealloc+0x81/0xe0 fs/gfs2/quota.c:112 rcu_do_batch kernel/rcu/tree.c:2194 [inline] rcu_core+0xcc4/0x1720 kernel/rcu/tree.c:2467 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x36/0x60 kernel/kcov.c:216 Code: 60 24 7e 7e 65 8b 15 61 24 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc900032c7070 EFLAGS: 00000246 RAX: ffffffff813aba56 RBX: ffffffff8ed1385b RCX: ffff88807dc9bc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffc900032c7270 RBP: ffffc900032c7198 R08: ffff88807dc9bc00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900032c7148 R13: dffffc0000000000 R14: ffffffff8ed1385a R15: ffffffff8ed1385c unwind_next_frame+0x1796/0x2970 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 tomoyo_realpath_from_path+0x59d/0x5d0 security/tomoyo/realpath.c:286 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1ea/0x590 security/tomoyo/file.c:723 tomoyo_path_mknod+0x143/0x190 security/tomoyo/tomoyo.c:251 security_path_mknod+0xf0/0x150 security/security.c:1715 may_o_create fs/namei.c:3310 [inline] lookup_open fs/namei.c:3451 [inline] open_last_lookups fs/namei.c:3556 [inline] path_openat+0xb38/0x3190 fs/namei.c:3786 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc0ec8a7407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffc62e96c40 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc0ed067880 RCX: 00007fc0ec8a7407 RDX: 0000000000080141 RSI: 000055c23ba8402e RDI: ffffffffffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001a4 R11: 0000000000000202 R12: 00000000ffffffff R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000000 Allocated by task 6700: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] init_sbd fs/gfs2/ops_fstype.c:77 [inline] gfs2_fill_super+0x11b/0x1f80 fs/gfs2/ops_fstype.c:1162 get_tree_bdev+0x3e4/0x510 fs/super.c:1591 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1344 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 6700: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 free_sbd fs/gfs2/ops_fstype.c:69 [inline] gfs2_fill_super+0x13c7/0x1f80 fs/gfs2/ops_fstype.c:1327 get_tree_bdev+0x3e4/0x510 fs/super.c:1591 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1344 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88807c6e8000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2680 bytes inside of freed 8192-byte region [ffff88807c6e8000, ffff88807c6ea000) The buggy address belongs to the physical page: page:ffffea0001f1ba00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c6e8 head:ffffea0001f1ba00 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 ffff888017842280 ffffea00006da200 dead000000000004 raw: 0000000000000000 0000000080020002 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5607, tgid 5607 (dhcpcd-run-hook), ts 48342166128, free_ts 48341306911 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0x1104/0x1f10 security/tomoyo/audit.c:264 tomoyo_supervisor+0x32d/0x1080 security/tomoyo/common.c:2089 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x14a/0x1e0 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0x1594/0x1a60 security/tomoyo/domain.c:881 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 security_bprm_check+0x62/0xa0 security/security.c:1103 search_binary_handler fs/exec.c:1763 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xa51/0x16f0 fs/exec.c:1892 do_execveat_common+0x51b/0x6c0 fs/exec.c:1998 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0x1104/0x1f10 security/tomoyo/audit.c:264 tomoyo_supervisor+0x32d/0x1080 security/tomoyo/common.c:2089 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x14a/0x1e0 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0x1594/0x1a60 security/tomoyo/domain.c:881 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 Memory state around the buggy address: ffff88807c6e8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c6e8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c6e8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c6e8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c6e8b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 24 7e and $0x7e,%al 2: 7e 65 jle 0x69 4: 8b 15 61 24 7e 7e mov 0x7e7e2461(%rip),%edx # 0x7e7e246b a: 81 e2 00 01 ff 00 and $0xff0100,%edx 10: 74 11 je 0x23 12: 81 fa 00 01 00 00 cmp $0x100,%edx 18: 75 35 jne 0x4f 1a: 83 b9 1c 16 00 00 00 cmpl $0x0,0x161c(%rcx) 21: 74 2c je 0x4f 23: 8b 91 f8 15 00 00 mov 0x15f8(%rcx),%edx * 29: 83 fa 02 cmp $0x2,%edx <-- trapping instruction 2c: 75 21 jne 0x4f 2e: 48 8b 91 00 16 00 00 mov 0x1600(%rcx),%rdx 35: 48 8b 32 mov (%rdx),%rsi 38: 48 8d 7e 01 lea 0x1(%rsi),%rdi 3c: 8b .byte 0x8b 3d: 89 fc mov %edi,%esp