================================================================== BUG: KASAN: use-after-free in dev_map_generic_redirect+0xa0/0x6f0 kernel/bpf/devmap.c:667 Read of size 8 at addr ffff88812a34f600 by task syz.2.1476/3854 CPU: 0 PID: 3854 Comm: syz.2.1476 Tainted: G W 5.15.178-syzkaller-00382-g7b2ee2ec80df #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106 print_address_description+0x87/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:444 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 dev_map_generic_redirect+0xa0/0x6f0 kernel/bpf/devmap.c:667 xdp_do_generic_redirect_map net/core/filter.c:4177 [inline] xdp_do_generic_redirect+0x42e/0xb40 net/core/filter.c:4236 do_xdp_generic+0x50b/0x7c0 net/core/dev.c:4919 __netif_receive_skb_core+0x1706/0x3640 net/core/dev.c:5324 __netif_receive_skb_one_core net/core/dev.c:5499 [inline] __netif_receive_skb+0x11c/0x530 net/core/dev.c:5615 process_backlog+0x31c/0x650 net/core/dev.c:6492 __napi_poll+0xc4/0x5a0 net/core/dev.c:7051 napi_poll net/core/dev.c:7118 [inline] net_rx_action+0x47d/0xc50 net/core/dev.c:7208 handle_softirqs+0x25e/0x5c0 kernel/softirq.c:565 __do_softirq+0xb/0xd kernel/softirq.c:603 do_softirq+0xf6/0x150 kernel/softirq.c:452 __local_bh_enable_ip+0x75/0x80 kernel/softirq.c:379 local_bh_enable+0x1f/0x30 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:818 [inline] ip_finish_output2+0xbef/0xf60 net/ipv4/ip_output.c:229 __ip_finish_output+0x162/0x360 net/ipv4/ip_output.c:-1 ip_finish_output+0x31/0x210 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x1d6/0x420 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] ip_send_skb+0xb0/0x140 net/ipv4/ip_output.c:1581 udp_send_skb+0x983/0x1160 net/ipv4/udp.c:991 udp_sendmsg+0x1d00/0x2aa0 net/ipv4/udp.c:1279 udpv6_sendmsg+0xbea/0x3180 net/ipv6/udp.c:1395 inet6_sendmsg+0xa1/0xc0 net/ipv6/af_inet6.c:660 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2436 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2490 __sys_sendmmsg+0x2bf/0x530 net/socket.c:2576 __do_sys_sendmmsg net/socket.c:2605 [inline] __se_sys_sendmmsg net/socket.c:2602 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2602 x64_sys_call+0x81d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f3f1803d169 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:00007f3f166a7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f3f18255fa0 RCX: 00007f3f1803d169 RDX: 0400000000000172 RSI: 0000200000003cc0 RDI: 0000000000000003 RBP: 00007f3f180be990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000004001c00 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3f18255fa0 R15: 00007ffc0baf1738 Allocated by task 2818: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc+0xdb/0x110 mm/kasan/common.c:512 __kasan_krealloc+0x93/0xd0 mm/kasan/common.c:580 kasan_krealloc include/linux/kasan.h:247 [inline] __do_krealloc mm/slab_common.c:1234 [inline] krealloc+0xbe/0x110 mm/slab_common.c:1271 push_jmp_history kernel/bpf/verifier.c:2119 [inline] is_state_visited kernel/bpf/verifier.c:11039 [inline] do_check+0x2633/0xf2c0 kernel/bpf/verifier.c:11179 do_check_common+0x909/0x1290 kernel/bpf/verifier.c:13457 do_check_main kernel/bpf/verifier.c:13520 [inline] bpf_check+0x3851/0x12c60 kernel/bpf/verifier.c:14091 bpf_prog_load+0x12ac/0x1b50 kernel/bpf/syscall.c:2333 __sys_bpf+0x4bc/0x760 kernel/bpf/syscall.c:4638 __do_sys_bpf kernel/bpf/syscall.c:4742 [inline] __se_sys_bpf kernel/bpf/syscall.c:4740 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:4740 x64_sys_call+0x87f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88812a34f600 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff88812a34f600, ffff88812a34f660) The buggy address belongs to the page: page:ffffea0004a8d3c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88812a34f980 pfn:0x12a34f flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004a83140 0000000f0000000f ffff888100042900 raw: ffff88812a34f980 0000000080200001 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 299, ts 26138521612, free_ts 26136036927 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1b/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5780 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1932 [inline] new_slab+0x9a/0x4e0 mm/slub.c:1995 ___slab_alloc+0x39e/0x830 mm/slub.c:3028 __slab_alloc+0x4a/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] kmem_cache_alloc_trace+0x147/0x270 mm/slub.c:3267 kmalloc include/linux/slab.h:603 [inline] dst_cow_metrics_generic+0x55/0x1c0 net/core/dst.c:206 dst_metrics_write_ptr include/net/dst.h:118 [inline] dst_metric_set include/net/dst.h:179 [inline] icmp6_dst_alloc+0x385/0x560 net/ipv6/route.c:3288 mld_sendpack+0x4db/0xbb0 net/ipv6/mcast.c:1809 mld_send_initial_cr net/ipv6/mcast.c:2239 [inline] ipv6_mc_dad_complete+0x283/0x5f0 net/ipv6/mcast.c:2247 addrconf_dad_completed+0x6d0/0xd80 net/ipv6/addrconf.c:4278 addrconf_dad_work+0xdc1/0x1710 net/ipv6/addrconf.c:-1 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3534 free_unref_page+0xe8/0x750 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5856 __vunmap+0x7c1/0x940 mm/vmalloc.c:2652 __vfree mm/vmalloc.c:2701 [inline] vfree+0x7f/0xb0 mm/vmalloc.c:2732 kvfree+0x26/0x40 mm/util.c:662 pcpu_mem_free mm/percpu.c:527 [inline] pcpu_free_chunk mm/percpu.c:1509 [inline] pcpu_destroy_chunk mm/percpu-vm.c:368 [inline] pcpu_balance_free+0x745/0x8e0 mm/percpu.c:2023 pcpu_balance_workfn+0xea6/0xee0 mm/percpu.c:2249 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 kthread+0x421/0x510 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88812a34f500: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88812a34f580: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff88812a34f600: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88812a34f680: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88812a34f700: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================