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BUG: KASAN: use-after-free in dev_map_generic_redirect+0xa0/0x6b0 kernel/bpf/devmap.c:667
Read of size 8 at addr ffff88811a1d9480 by task kworker/u4:2/44

CPU: 0 PID: 44 Comm: kworker/u4:2 Not tainted 5.15.180-syzkaller-00024-g88c4075c39ed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
Call Trace:
 <IRQ>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 mm/kasan/report.c:444
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 dev_map_generic_redirect+0xa0/0x6b0 kernel/bpf/devmap.c:667
 xdp_do_generic_redirect_map net/core/filter.c:4177 [inline]
 xdp_do_generic_redirect+0x40e/0xa80 net/core/filter.c:4236
 do_xdp_generic+0x516/0x7a0 net/core/dev.c:4950
 __netif_receive_skb_core+0x12ac/0x2f10 net/core/dev.c:5355
 __netif_receive_skb_one_core net/core/dev.c:5530 [inline]
 __netif_receive_skb+0x72/0x280 net/core/dev.c:5646
 process_backlog+0x368/0x600 net/core/dev.c:6523
 __napi_poll+0xbe/0x590 net/core/dev.c:7082
 napi_poll net/core/dev.c:7149 [inline]
 net_rx_action+0x371/0x8e0 net/core/dev.c:7239
 handle_softirqs+0x250/0x560 kernel/softirq.c:565
 __do_softirq+0xb/0xd kernel/softirq.c:603
 do_softirq+0xc6/0x120 kernel/softirq.c:452
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x75/0x80 kernel/softirq.c:379
 __raw_read_unlock_bh include/linux/rwlock_api_smp.h:251 [inline]
 _raw_read_unlock_bh+0x29/0x30 kernel/locking/spinlock.c:284
 wg_socket_send_skb_to_peer+0x172/0x1d0 drivers/net/wireguard/socket.c:184
 wg_socket_send_buffer_to_peer+0x118/0x170 drivers/net/wireguard/socket.c:200
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
 wg_packet_handshake_send_worker+0x1d4/0x240 drivers/net/wireguard/send.c:51
 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
 kthread+0x411/0x500 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 2201:
 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 mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc+0x13d/0x2c0 mm/slub.c:4431
 __kmalloc_node include/linux/slab.h:484 [inline]
 kmalloc_node include/linux/slab.h:639 [inline]
 bpf_map_kmalloc_node+0xb9/0x140 kernel/bpf/syscall.c:432
 __dev_map_alloc_node+0x5a/0x4d0 kernel/bpf/devmap.c:850
 __dev_map_update_elem kernel/bpf/devmap.c:914 [inline]
 dev_map_update_elem+0x1bc/0x330 kernel/bpf/devmap.c:933
 bpf_map_update_value+0x30e/0x3e0 kernel/bpf/syscall.c:223
 map_update_elem+0x5bb/0x740 kernel/bpf/syscall.c:1165
 __sys_bpf+0x40c/0x730 kernel/bpf/syscall.c:4618
 __do_sys_bpf kernel/bpf/syscall.c:4734 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4732 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:4732
 x64_sys_call+0x4b9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322
 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

Freed by task 1184:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1749
 slab_free mm/slub.c:3521 [inline]
 kfree+0xc4/0x270 mm/slub.c:4583
 dev_map_free+0x580/0x6b0 kernel/bpf/devmap.c:237
 bpf_map_free_deferred+0x10e/0x1e0 kernel/bpf/syscall.c:481
 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
 kthread+0x411/0x500 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff88811a1d9480
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 0 bytes inside of
 96-byte region [ffff88811a1d9480, ffff88811a1d94e0)
The buggy address belongs to the page:
page:ffffea0004687640 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88811a1d9600 pfn:0x11a1d9
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea000469fac0 0000001600000016 ffff888100042900
raw: ffff88811a1d9600 000000008020001f 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 157, ts 7163370232, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485
 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5781
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1932 [inline]
 new_slab+0xa1/0x4d0 mm/slub.c:1995
 ___slab_alloc+0x381/0x810 mm/slub.c:3028
 __slab_alloc+0x49/0x90 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc_trace+0x146/0x270 mm/slub.c:3267
 kmalloc include/linux/slab.h:616 [inline]
 kzalloc include/linux/slab.h:747 [inline]
 mmu_notifier_subscriptions_init include/linux/mmu_notifier.h:516 [inline]
 mm_init+0x36b/0x980 kernel/fork.c:1123
 dup_mm kernel/fork.c:1519 [inline]
 copy_mm+0x1dd/0x1390 kernel/fork.c:1574
 copy_process+0x1159/0x3250 kernel/fork.c:2263
 kernel_clone+0x23f/0x940 kernel/fork.c:2661
 __do_sys_clone kernel/fork.c:2787 [inline]
 __se_sys_clone kernel/fork.c:2771 [inline]
 __x64_sys_clone+0x176/0x1d0 kernel/fork.c:2771
 x64_sys_call+0x41f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:57
 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
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88811a1d9380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88811a1d9400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88811a1d9480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                   ^
 ffff88811a1d9500: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
 ffff88811a1d9580: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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