================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88805eb7582a by task syz.7.1611/12308 CPU: 0 PID: 12308 Comm: syz.7.1611 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 rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 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:sk_filter_trim_cap+0x0/0x8d0 net/core/filter.c:127 Code: ff e8 24 05 fc 01 89 d9 80 e1 07 fe c1 38 c1 7c a5 48 89 df e8 71 c9 6b f9 48 8b 5c 24 10 eb 96 66 2e 0f 1f 84 00 00 00 00 00 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc9000c2df758 EFLAGS: 00000246 RAX: ffffffff8923a68a RBX: 7fffffffffffffff RCX: 0000000000080000 RDX: 0000000000000001 RSI: ffff888063e67140 RDI: ffff88807d684800 RBP: ffffc9000c2df910 R08: ffff888064380007 R09: 1ffff1100c870000 R10: dffffc0000000000 R11: ffffed100c870001 R12: ffff88807d684800 R13: ffffc9000c2df860 R14: ffff88807d680e60 R15: dffffc0000000000 sk_filter include/linux/filter.h:864 [inline] unix_dgram_sendmsg+0x937/0x1720 net/unix/af_unix.c:2035 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595 ___sys_sendmsg+0x220/0x290 net/socket.c:2649 __sys_sendmmsg+0x275/0x4a0 net/socket.c:2735 __do_sys_sendmmsg net/socket.c:2764 [inline] __se_sys_sendmmsg net/socket.c:2761 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761 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: 0033:0x7ffb0378ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffb045d9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007ffb039b5fa0 RCX: 00007ffb0378ebe9 RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007ffb03811e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffb039b6038 R14: 00007ffb039b5fa0 R15: 00007ffcf1113188 Allocated by task 6962: 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] batadv_forw_packet_alloc+0x1e9/0x390 net/batman-adv/send.c:519 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:561 [inline] batadv_iv_ogm_queue_add+0x77b/0xcf0 net/batman-adv/bat_iv_ogm.c:669 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:848 [inline] batadv_iv_ogm_schedule+0xab3/0xe90 net/batman-adv/bat_iv_ogm.c:867 batadv_iv_send_outstanding_bat_ogm_packet+0x731/0x840 net/batman-adv/bat_iv_ogm.c:1711 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 1313: 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 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xd2c/0x1020 kernel/workqueue.c:1804 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1746 [inline] __run_timers+0x558/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 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 The buggy address belongs to the object at ffff88805eb75800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88805eb75800, ffff88805eb75a00) The buggy address belongs to the physical page: page:ffffea00017add00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5eb74 head:ffffea00017add00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017841c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 10599, tgid 10599 (kworker/u4:14), ts 413633673683, free_ts 391571838354 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] batadv_forw_packet_alloc+0x1e9/0x390 net/batman-adv/send.c:519 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:561 [inline] batadv_iv_ogm_queue_add+0x77b/0xcf0 net/batman-adv/bat_iv_ogm.c:669 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:848 [inline] batadv_iv_ogm_schedule+0xab3/0xe90 net/batman-adv/bat_iv_ogm.c:867 batadv_iv_send_outstanding_bat_ogm_packet+0x731/0x840 net/batman-adv/bat_iv_ogm.c:1711 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 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] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509 kmem_cache_zalloc include/linux/slab.h:711 [inline] jbd2_alloc_handle include/linux/jbd2.h:1602 [inline] new_handle fs/jbd2/transaction.c:461 [inline] jbd2__journal_start+0x140/0x5b0 fs/jbd2/transaction.c:488 __ext4_journal_start_sb+0x203/0x570 fs/ext4/ext4_jbd2.c:112 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x93/0x110 fs/ext4/inode.c:6103 __mark_inode_dirty+0x2b4/0xc80 fs/fs-writeback.c:2455 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x197/0x1b0 fs/inode.c:2210 ext4_page_mkwrite+0x1f3/0x1210 fs/ext4/inode.c:6224 Memory state around the buggy address: ffff88805eb75700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805eb75780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805eb75800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805eb75880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805eb75900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e8 24 05 fc 01 call 0x1fc0529 5: 89 d9 mov %ebx,%ecx 7: 80 e1 07 and $0x7,%cl a: fe c1 inc %cl c: 38 c1 cmp %al,%cl e: 7c a5 jl 0xffffffb5 10: 48 89 df mov %rbx,%rdi 13: e8 71 c9 6b f9 call 0xf96bc989 18: 48 8b 5c 24 10 mov 0x10(%rsp),%rbx 1d: eb 96 jmp 0xffffffb5 1f: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 26: 00 00 00 * 29: f3 0f 1e fa endbr64 <-- trapping instruction 2d: 55 push %rbp 2e: 48 89 e5 mov %rsp,%rbp 31: 41 57 push %r15 33: 41 56 push %r14 35: 41 55 push %r13 37: 41 54 push %r12 39: 53 push %rbx 3a: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 3e: 48 rex.W