================================================================== BUG: KASAN: use-after-free in ieee80211_monitor_select_queue+0x23a/0x240 net/mac80211/iface.c:909 Read of size 2 at addr ffff888056eccdfb by task syz.3.1237/8496 CPU: 1 PID: 8496 Comm: syz.3.1237 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 ieee80211_monitor_select_queue+0x23a/0x240 net/mac80211/iface.c:909 netdev_core_pick_tx+0x12c/0x360 net/core/dev.c:4245 __dev_queue_xmit+0xb45/0x3810 net/core/dev.c:4331 packet_snd net/packet/af_packet.c:3133 [inline] packet_sendmsg+0x3b95/0x4de0 net/packet/af_packet.c:3164 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5ed/0x9a0 net/socket.c:2519 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x1c3/0x2b0 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f82aff9e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f82b0e71028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f82b0226090 RCX: 00007f82aff9e0d9 RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000007 RBP: 00007f82b0035024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f82b0226128 R14: 00007f82b0226090 R15: 00007ffcdd4e4328 Allocated by task 8245: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node_track_caller+0xb0/0x240 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x226/0x7d0 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1303 [inline] alloc_skb_with_frags+0xa7/0x710 net/core/skbuff.c:6186 sock_alloc_send_pskb+0x87f/0x9a0 net/core/sock.c:2764 sock_alloc_send_skb include/net/sock.h:1976 [inline] __ip_append_data+0x260a/0x38d0 net/ipv4/ip_output.c:1127 ip_make_skb+0x227/0x440 net/ipv4/ip_output.c:1674 udp_sendmsg+0x1b04/0x23d0 net/ipv4/udp.c:1276 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5ed/0x9a0 net/socket.c:2519 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2573 __sys_sendmmsg+0x2c3/0x510 net/socket.c:2659 __do_sys_sendmmsg net/socket.c:2688 [inline] __se_sys_sendmmsg net/socket.c:2685 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2685 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888056eccc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 507 bytes inside of 512-byte region [ffff888056eccc00, ffff888056ecce00) The buggy address belongs to the physical page: page:ffffea00015bb300 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888056ecec00 pfn:0x56ecc head:ffffea00015bb300 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000c02f08 ffffea0000a4c108 ffff888017441c80 raw: ffff888056ecec00 0000000000100006 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 4275, tgid 4275 (syz-executor), ts 67790424078, free_ts 20476403478 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] fib6_info_alloc+0x2e/0xe0 net/ipv6/ip6_fib.c:156 ip6_route_info_create+0x455/0x1220 net/ipv6/route.c:3796 ip6_route_add+0x24/0x130 net/ipv6/route.c:3892 addrconf_prefix_route+0x249/0x320 net/ipv6/addrconf.c:2449 inet6_addr_add+0x502/0x9c0 net/ipv6/addrconf.c:3023 inet6_rtm_newaddr+0x6c9/0x8f0 net/ipv6/addrconf.c:4980 rtnetlink_rcv_msg+0x863/0xfb0 net/core/rtnetlink.c:6166 netlink_rcv_skb+0x1ef/0x440 net/netlink/af_netlink.c:2516 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 free_contig_range+0x9d/0x150 mm/page_alloc.c:9626 destroy_args+0xef/0xa0e mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x257/0x800 init/main.c:1309 do_initcall_level+0x13d/0x1ed init/main.c:1382 do_initcalls+0x4b/0x8a init/main.c:1398 kernel_init_freeable+0x401/0x5ab init/main.c:1637 kernel_init+0x19/0x1b0 init/main.c:1525 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888056eccc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056eccd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888056eccd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888056ecce00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056ecce80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================