================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88805f4ea82a by task syz.0.797/8780 CPU: 1 UID: 0 PID: 8780 Comm: syz.0.797 Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5250 Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 e9 27 05 00 00 4c 8b 75 d0 4c 89 e7 e8 ff b2 bf 09 e8 1a 66 35 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc90004477558 EFLAGS: 00000282 RAX: 9bf5461276860f00 RBX: 0000000000000000 RCX: 9bf5461276860f00 RDX: 0000000000000000 RSI: ffffffff8d737223 RDI: ffffffff8bc0fe60 RBP: ffffc900044775b0 R08: ffffffff8f7daf77 R09: 1ffffffff1efb5ee R10: dffffc0000000000 R11: fffffbfff1efb5ef R12: ffff88802e398000 R13: dffffc0000000000 R14: ffff88802fc85a00 R15: ffff8880b893a558 context_switch kernel/sched/core.c:5385 [inline] __schedule+0x1697/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 rdmsr_safe_on_cpu+0x150/0x230 arch/x86/lib/msr-smp.c:181 msr_read+0x14d/0x250 arch/x86/kernel/msr.c:66 vfs_read+0x1fd/0x980 fs/read_write.c:568 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd8638e969 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:00007fbd87252038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fbd865b5fa0 RCX: 00007fbd8638e969 RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000004 RBP: 00007fbd86410ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbd865b5fa0 R15: 00007ffdb1596578 Allocated by task 6861: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] rose_add_node+0x23a/0xde0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa48/0xfb0 net/rose/rose_route.c:747 rose_ioctl+0x3ce/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8030: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x193/0x440 mm/slub.c:4841 rose_rt_device_down+0x66d/0x6c0 net/rose/rose_route.c:522 rose_device_event+0x603/0x6a0 net/rose/af_rose.c:248 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline] call_netdevice_notifiers net/core/dev.c:2228 [inline] dev_close_many+0x29c/0x410 net/core/dev.c:1731 netif_close+0x158/0x210 net/core/dev.c:1744 dev_close+0x10a/0x220 net/core/dev_api.c:219 bpq_device_event+0x2f4/0x600 drivers/net/hamradio/bpqether.c:528 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline] call_netdevice_notifiers net/core/dev.c:2228 [inline] dev_close_many+0x29c/0x410 net/core/dev.c:1731 netif_close+0x158/0x210 net/core/dev.c:1744 dev_close+0x10a/0x220 net/core/dev_api.c:219 bond_setup_by_slave+0x5f/0x3f0 drivers/net/bonding/bond_main.c:1627 bond_enslave+0x7b4/0x3a40 drivers/net/bonding/bond_main.c:2039 bond_do_ioctl+0x635/0x9b0 drivers/net/bonding/bond_main.c:4684 bond_siocdevprivate+0x17e/0x350 drivers/net/bonding/bond_main.c:-1 dev_siocdevprivate net/core/dev_ioctl.c:521 [inline] dev_ifsioc+0xb54/0xf00 net/core/dev_ioctl.c:631 dev_ioctl+0x84c/0x1150 net/core/dev_ioctl.c:848 sock_ioctl+0x719/0x790 net/socket.c:1236 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805f4ea800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88805f4ea800, ffff88805f4eaa00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805f4eac00 pfn:0x5f4e8 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801a041c80 ffffea00009e8b10 ffffea00009cba10 raw: ffff88805f4eac00 0000000000100006 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801a041c80 ffffea00009e8b10 ffffea00009cba10 head: ffff88805f4eac00 0000000000100006 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00017d3a01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 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 5828, tgid 5828 (syz-executor), ts 106351970753, free_ts 38255677948 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21c7/0x22a0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x4b3/0x1360 net/ipv6/route.c:3802 addrconf_f6i_alloc+0x1c6/0x3f0 net/ipv6/route.c:4631 ipv6_add_addr+0x56e/0x1090 net/ipv6/addrconf.c:1121 addrconf_add_linklocal+0x28c/0x6c0 net/ipv6/addrconf.c:3313 addrconf_addr_gen+0x490/0x580 net/ipv6/addrconf.c:3444 addrconf_init_auto_addrs+0x7b6/0xb80 net/ipv6/addrconf.c:-1 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3741 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb05/0xcd0 mm/page_alloc.c:2725 __free_pages mm/page_alloc.c:5080 [inline] free_contig_range+0x159/0x440 mm/page_alloc.c:6936 destroy_args+0x86/0x460 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x3cf/0x410 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x233/0x820 init/main.c:1257 do_initcall_level+0x137/0x1f0 init/main.c:1319 do_initcalls+0x69/0xd0 init/main.c:1335 kernel_init_freeable+0x3d9/0x570 init/main.c:1567 kernel_init+0x1d/0x1d0 init/main.c:1457 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88805f4ea700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f4ea780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805f4ea800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805f4ea880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805f4ea900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 3c 01 00 00 je 0x142 6: 48 85 db test %rbx,%rbx 9: 0f 85 63 01 00 00 jne 0x172 f: e9 27 05 00 00 jmp 0x53b 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 ff b2 bf 09 call 0x9bfb31f 20: e8 1a 66 35 00 call 0x35663f 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 18 16 00 lea 0x1618(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al