================================================================== BUG: KASAN: use-after-free in rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88814074c82a by task syz.5.669/6752 CPU: 1 PID: 6752 Comm: syz.5.669 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 rose_timer_expiry+0x470/0x490 net/rose/rose_timer.c:183 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 3e 14 d3 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 06 94 a6 f7 65 8b 05 a7 a3 57 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900039bf420 EFLAGS: 00000206 RAX: 3764be8ae96f8d00 RBX: 0000000000000a02 RCX: 3764be8ae96f8d00 RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001 RBP: ffffc900039bf4b0 R08: dffffc0000000000 R09: fffffbfff1ff3621 R10: fffffbfff1ff3621 R11: 1ffffffff1ff3620 R12: dffffc0000000000 R13: 1ffff11017226aab R14: ffff88802221f050 R15: 1ffff92000737e84 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1538 [inline] __pagevec_lru_add+0x142a/0x17c0 mm/swap.c:1055 lru_cache_add+0x516/0x750 mm/swap.c:453 shmem_getpage_gfp+0x1868/0x2d40 mm/shmem.c:1945 shmem_fault+0x1a9/0x520 mm/shmem.c:2118 __do_fault+0x141/0x330 mm/memory.c:3928 do_read_fault mm/memory.c:4264 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2949/0x43c0 mm/memory.c:4883 faultin_page mm/gup.c:976 [inline] __get_user_pages+0x93e/0x11c0 mm/gup.c:1197 populate_vma_page_range+0x213/0x290 mm/gup.c:1529 __mm_populate+0x26f/0x3a0 mm/gup.c:1638 mm_populate include/linux/mm.h:2632 [inline] vm_mmap_pgoff+0x203/0x2b0 mm/util.c:556 ksys_mmap_pgoff+0x140/0x780 mm/mmap.c:1623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f36ee50b929 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:00007f36ec373038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f36ee732fa0 RCX: 00007f36ee50b929 RDX: b635773f07ebbeef RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f36ee58db39 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f36ee732fa0 R15: 00007ffcc7ead468 Allocated by task 4282: 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 mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:604 [inline] rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85 rose_rt_ioctl+0x9db/0xe20 net/rose/rose_route.c:745 rose_ioctl+0x27a/0x790 net/rose/af_rose.c:1372 sock_do_ioctl+0xd3/0x2f0 net/socket.c:1140 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88814074c800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of 512-byte region [ffff88814074c800, ffff88814074ca00) The buggy address belongs to the page: page:ffffea000501d300 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88814074c800 pfn:0x14074c head:ffffea000501d300 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 ffffea0005202408 ffffea0005317908 ffff888016841c80 raw: ffff88814074c800 0000000000100008 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 1, ts 1981695705, free_ts 0 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2031 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] slab_alloc mm/slub.c:3228 [inline] __kmalloc_track_caller+0x1cb/0x330 mm/slub.c:4925 __do_krealloc mm/slab_common.c:1244 [inline] krealloc+0x5a/0xf0 mm/slab_common.c:1277 add_sysfs_param+0xe8/0x930 kernel/params.c:651 kernel_add_sysfs_param+0xaf/0x120 kernel/params.c:812 param_sysfs_builtin+0x164/0x1e0 kernel/params.c:851 param_sysfs_init+0x66/0x70 kernel/params.c:972 do_one_initcall+0x1ee/0x680 init/main.c:1302 do_initcall_level+0x137/0x1f0 init/main.c:1375 do_initcalls+0x4b/0x90 init/main.c:1391 kernel_init_freeable+0x3ce/0x560 init/main.c:1615 kernel_init+0x19/0x1b0 init/main.c:1506 page_owner free stack trace missing Memory state around the buggy address: ffff88814074c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88814074c780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88814074c800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88814074c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88814074c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== vkms_vblank_simulate: vblank timer overrun ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 3e 14 d3 f7 call 0xf7d31445 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 06 94 a6 f7 call 0xf7a69435 <-- trapping instruction 2f: 65 8b 05 a7 a3 57 76 mov %gs:0x7657a3a7(%rip),%eax # 0x7657a3dd 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss