================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88802ad26c2a by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.102-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:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148 Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d e3 e6 3a 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56 RSP: 0018:ffffc90000187de0 EFLAGS: 000002c6 RAX: 76ad70d551134d00 RBX: ffffffff8161914b RCX: 76ad70d551134d00 RDX: 0000000000000001 RSI: ffffffff8aaab9c0 RDI: ffffffff8afc66c0 RBP: ffffc90000187f20 R08: ffff8880b8f36d4b R09: 1ffff110171e6da9 R10: dffffc0000000000 R11: ffffed10171e6daa R12: ffffffff8e4a8828 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1100364e780 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:753 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x1eb/0x510 kernel/sched/idle.c:282 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380 start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323 secondary_startup_64_no_verify+0x179/0x17b Allocated by task 7994: 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 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] io_alloc_async_data+0xb7/0x1c0 io_uring/io_uring.c:1750 io_setup_async_rw+0xbc/0x550 io_uring/rw.c:537 io_write+0xe92/0x18e0 io_uring/rw.c:1025 io_issue_sqe+0x289/0xc90 io_uring/io_uring.c:1868 io_queue_sqe io_uring/io_uring.c:2052 [inline] io_submit_sqe io_uring/io_uring.c:2319 [inline] io_submit_sqes+0xa8a/0x1d00 io_uring/io_uring.c:2434 __do_sys_io_uring_enter io_uring/io_uring.c:3778 [inline] __se_sys_io_uring_enter+0x2de/0x22e0 io_uring/io_uring.c:3713 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 ffff88802ad26c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88802ad26c00, ffff88802ad26e00) The buggy address belongs to the physical page: page:ffffea0000ab4900 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802ad24000 pfn:0x2ad24 head:ffffea0000ab4900 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 ffffea0001776010 ffffea000176aa10 raw: ffff88802ad24000 000000000010000b 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 2734, tgid 2734 (kworker/u4:0), ts 22701574540, 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: ffff88802ad26b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802ad26b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802ad26c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802ad26c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ad26d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: cc int3 3: cc int3 4: cc int3 5: cc int3 6: cc int3 7: f3 0f 1e fa endbr64 b: 0f 0b ud2 d: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 14: 00 00 00 17: f3 0f 1e fa endbr64 1b: 66 90 xchg %ax,%ax 1d: 0f 00 2d e3 e6 3a 00 verw 0x3ae6e3(%rip) # 0x3ae707 24: f3 0f 1e fa endbr64 28: fb sti 29: f4 hlt * 2a: c3 ret <-- trapping instruction 2b: cc int3 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: cc int3 31: cc int3 32: cc int3 33: cc int3 34: cc int3 35: cc int3 36: cc int3 37: 66 0f 1f 00 nopw (%rax) 3b: 55 push %rbp 3c: 41 57 push %r15 3e: 41 56 push %r14