==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1131 [inline]
BUG: KASAN: use-after-free in consume_skb+0x3a/0x1f0 net/core/skbuff.c:926
Read of size 4 at addr ffff88811ab454ac by task kworker/1:4/612

CPU: 1 PID: 612 Comm: kworker/1:4 Not tainted 5.15.184-syzkaller-00129-g4032a894ccb2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events bpf_map_free_deferred
Call Trace:
 <TASK>
 __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
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
 __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 refcount_read include/linux/refcount.h:147 [inline]
 skb_unref include/linux/skbuff.h:1131 [inline]
 consume_skb+0x3a/0x1f0 net/core/skbuff.c:926
 __sk_msg_free+0x4f4/0x560 net/core/skmsg.c:205
 sk_msg_free net/core/skmsg.c:218 [inline]
 __sk_psock_purge_ingress_msg net/core/skmsg.c:773 [inline]
 __sk_psock_zap_ingress net/core/skmsg.c:791 [inline]
 sk_psock_stop+0x4c9/0x570 net/core/skmsg.c:809
 sk_psock_drop+0x226/0x300 net/core/skmsg.c:848
 sk_psock_put include/linux/skmsg.h:463 [inline]
 sock_map_unref+0x3c2/0x420 net/core/sock_map.c:184
 sock_map_free+0x134/0x2a0 net/core/sock_map.c:354
 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
 </TASK>

Allocated by task 3187:
 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_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3255
 skb_clone+0x1cf/0x360 net/core/skbuff.c:1547
 sk_psock_verdict_recv+0x53/0x800 net/core/skmsg.c:1187
 unix_read_sock+0x10a/0x2c0 net/unix/af_unix.c:2428
 sk_psock_verdict_data_ready+0x115/0x170 net/core/skmsg.c:1230
 unix_dgram_sendmsg+0x11e6/0x1880 net/unix/af_unix.c:1942
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg net/socket.c:2526 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2526
 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 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 391:
 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]
 kmem_cache_free+0x100/0x320 mm/slub.c:3539
 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1
 __kfree_skb net/core/skbuff.c:758 [inline]
 kfree_skb_reason net/core/skbuff.c:778 [inline]
 kfree_skb+0xc1/0x2f0 net/core/skbuff.c:792
 sock_drop include/linux/skmsg.h:312 [inline]
 sk_psock_backlog+0xa85/0xd80 net/core/skmsg.c:684
 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 ffff88811ab453c0
 which belongs to the cache skbuff_head_cache of size 248
The buggy address is located 236 bytes inside of
 248-byte region [ffff88811ab453c0, ffff88811ab454b8)
The buggy address belongs to the page:
page:ffffea00046ad140 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11ab45
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 0000000900000001 ffff8881081ab080
raw: 0000000000000000 00000000000c000c 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 612, ts 125319039093, free_ts 125292635975
 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+0x138/0x260 mm/slub.c:3255
 kmem_cache_alloc_node include/linux/slab.h:489 [inline]
 __alloc_skb+0xe0/0x740 net/core/skbuff.c:416
 alloc_skb include/linux/skbuff.h:1183 [inline]
 mld_newpack+0x13a/0x9d0 net/ipv6/mcast.c:1746
 add_grhead+0x5e/0x290 net/ipv6/mcast.c:1857
 add_grec+0xd41/0x1100 net/ipv6/mcast.c:1995
 mld_send_cr net/ipv6/mcast.c:2121 [inline]
 mld_ifc_work+0x75d/0xbe0 net/ipv6/mcast.c:2659
 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
 kthread+0x411/0x500 kernel/kthread.c:337
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+0x542/0x550 mm/page_alloc.c:3534
 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0x6c/0x100 mm/page_alloc.c:5857
 bpf_ringbuf_free kernel/bpf/ringbuf.c:195 [inline]
 ringbuf_map_free+0xb6/0x110 kernel/bpf/ringbuf.c:204
 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

Memory state around the buggy address:
 ffff88811ab45380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
 ffff88811ab45400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811ab45480: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc
                                  ^
 ffff88811ab45500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811ab45580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
==================================================================
==================================================================
BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3521 [inline]
BUG: KASAN: double-free or invalid-free in kmem_cache_free+0x100/0x320 mm/slub.c:3539

CPU: 1 PID: 612 Comm: kworker/1:4 Tainted: G    B             5.15.184-syzkaller-00129-g4032a894ccb2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events bpf_map_free_deferred
Call Trace:
 <TASK>
 __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_invalid_free+0x58/0x90 mm/kasan/report.c:370
 ____kasan_slab_free+0x13d/0x160 mm/kasan/common.c:-1
 __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]
 kmem_cache_free+0x100/0x320 mm/slub.c:3539
 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1
 __kfree_skb net/core/skbuff.c:758 [inline]
 consume_skb+0xb3/0x1f0 net/core/skbuff.c:930
 __sk_msg_free+0x4f4/0x560 net/core/skmsg.c:205
 sk_msg_free net/core/skmsg.c:218 [inline]
 __sk_psock_purge_ingress_msg net/core/skmsg.c:773 [inline]
 __sk_psock_zap_ingress net/core/skmsg.c:791 [inline]
 sk_psock_stop+0x4c9/0x570 net/core/skmsg.c:809
 sk_psock_drop+0x226/0x300 net/core/skmsg.c:848
 sk_psock_put include/linux/skmsg.h:463 [inline]
 sock_map_unref+0x3c2/0x420 net/core/sock_map.c:184
 sock_map_free+0x134/0x2a0 net/core/sock_map.c:354
 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
 </TASK>

Allocated by task 3187:
 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_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3255
 skb_clone+0x1cf/0x360 net/core/skbuff.c:1547
 sk_psock_verdict_recv+0x53/0x800 net/core/skmsg.c:1187
 unix_read_sock+0x10a/0x2c0 net/unix/af_unix.c:2428
 sk_psock_verdict_data_ready+0x115/0x170 net/core/skmsg.c:1230
 unix_dgram_sendmsg+0x11e6/0x1880 net/unix/af_unix.c:1942
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg net/socket.c:2526 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2526
 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 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 391:
 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]
 kmem_cache_free+0x100/0x320 mm/slub.c:3539
 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1
 __kfree_skb net/core/skbuff.c:758 [inline]
 kfree_skb_reason net/core/skbuff.c:778 [inline]
 kfree_skb+0xc1/0x2f0 net/core/skbuff.c:792
 sock_drop include/linux/skmsg.h:312 [inline]
 sk_psock_backlog+0xa85/0xd80 net/core/skmsg.c:684
 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 ffff88811ab453c0
 which belongs to the cache skbuff_head_cache of size 248
The buggy address is located 0 bytes inside of
 248-byte region [ffff88811ab453c0, ffff88811ab454b8)
The buggy address belongs to the page:
page:ffffea00046ad140 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11ab45
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 0000000900000001 ffff8881081ab080
raw: 0000000000000000 00000000000c000c 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 612, ts 125319039093, free_ts 125292635975
 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+0x138/0x260 mm/slub.c:3255
 kmem_cache_alloc_node include/linux/slab.h:489 [inline]
 __alloc_skb+0xe0/0x740 net/core/skbuff.c:416
 alloc_skb include/linux/skbuff.h:1183 [inline]
 mld_newpack+0x13a/0x9d0 net/ipv6/mcast.c:1746
 add_grhead+0x5e/0x290 net/ipv6/mcast.c:1857
 add_grec+0xd41/0x1100 net/ipv6/mcast.c:1995
 mld_send_cr net/ipv6/mcast.c:2121 [inline]
 mld_ifc_work+0x75d/0xbe0 net/ipv6/mcast.c:2659
 process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
 worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
 kthread+0x411/0x500 kernel/kthread.c:337
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+0x542/0x550 mm/page_alloc.c:3534
 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0x6c/0x100 mm/page_alloc.c:5857
 bpf_ringbuf_free kernel/bpf/ringbuf.c:195 [inline]
 ringbuf_map_free+0xb6/0x110 kernel/bpf/ringbuf.c:204
 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

Memory state around the buggy address:
 ffff88811ab45280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88811ab45300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88811ab45380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
                                           ^
 ffff88811ab45400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811ab45480: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc
==================================================================