================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff888024311c2a by task syz.1.501/7753 CPU: 1 PID: 7753 Comm: syz.1.501 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:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:__might_resched+0x179/0x610 kernel/sched/core.c:10173 Code: 03 43 0f b6 04 2c 84 c0 0f 85 45 03 00 00 41 8b 06 c1 e0 08 44 01 f8 3b 44 24 2c 75 61 48 c7 84 24 a0 00 00 00 00 00 00 00 9c <8f> 84 24 a0 00 00 00 f6 84 24 a1 00 00 00 02 74 43 4c 8d 7a 2c 4c RSP: 0018:ffffc9000fccfb18 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff92001f99f6c RCX: 6aa797a2f8249d00 RDX: ffff888018759e00 RSI: ffffffff8aaacbc0 RDI: ffffffff8afc6780 RBP: ffffc9000fccfc38 R08: ffffc9000fccf687 R09: 1ffff92001f99ed0 R10: dffffc0000000000 R11: fffff52001f99ed1 R12: 1ffff110030eb447 R13: dffffc0000000000 R14: ffff88801875a23c R15: 0000000000000000 __might_fault+0x71/0x120 mm/memory.c:5944 do_recvmmsg+0x389/0x7d0 net/socket.c:2956 __sys_recvmmsg net/socket.c:3029 [inline] __do_sys_recvmmsg net/socket.c:3052 [inline] __se_sys_recvmmsg net/socket.c:3045 [inline] __x64_sys_recvmmsg+0x191/0x240 net/socket.c:3045 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: 0033:0x7fce9658ebe9 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:00007fce973ee038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fce967b6090 RCX: 00007fce9658ebe9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006 RBP: 00007fce96611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fce967b6128 R14: 00007fce967b6090 R15: 00007fff40a2ce48 Allocated by task 5917: 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] rose_add_node+0x23a/0xdd0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa42/0xfb0 net/rose/rose_route.c:740 rose_ioctl+0x3cf/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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 7728: 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 rose_rt_device_down+0x43d/0x490 net/rose/rose_route.c:515 rose_device_event+0x604/0x690 net/rose/af_rose.c:248 notifier_call_chain+0x197/0x390 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] __dev_notify_flags+0x18e/0x2e0 net/core/dev.c:-1 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8750 dev_ifsioc+0x6a7/0xe20 net/core/dev_ioctl.c:529 dev_ioctl+0x7e2/0x1170 net/core/dev_ioctl.c:786 sock_do_ioctl+0x226/0x2f0 net/socket.c:1236 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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 ffff888024311c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff888024311c00, ffff888024311e00) The buggy address belongs to the physical page: page:ffffea000090c400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24310 head:ffffea000090c400 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017841c80 ffffea000170af00 dead000000000002 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1339, tgid 1339 (kworker/u4:3), ts 9439690449, free_ts 0 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] alloc_bprm+0x56/0x9c0 fs/exec.c:1538 kernel_execve+0x98/0x9c0 fs/exec.c:2023 call_usermodehelper_exec_async+0x20b/0x350 kernel/umh.c:110 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 page_owner free stack trace missing Memory state around the buggy address: ffff888024311b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888024311b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888024311c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024311c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024311d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== sched: RT throttling activated ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 43 0f b6 04 2c movzbl (%r12,%r13,1),%eax 5: 84 c0 test %al,%al 7: 0f 85 45 03 00 00 jne 0x352 d: 41 8b 06 mov (%r14),%eax 10: c1 e0 08 shl $0x8,%eax 13: 44 01 f8 add %r15d,%eax 16: 3b 44 24 2c cmp 0x2c(%rsp),%eax 1a: 75 61 jne 0x7d 1c: 48 c7 84 24 a0 00 00 movq $0x0,0xa0(%rsp) 23: 00 00 00 00 00 28: 9c pushf * 29: 8f 84 24 a0 00 00 00 pop 0xa0(%rsp) <-- trapping instruction 30: f6 84 24 a1 00 00 00 testb $0x2,0xa1(%rsp) 37: 02 38: 74 43 je 0x7d 3a: 4c 8d 7a 2c lea 0x2c(%rdx),%r15 3e: 4c rex.WR