================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0xff/0x7c80 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff888077a01670 by task kworker/u4:5/68 CPU: 1 PID: 68 Comm: kworker/u4:5 Not tainted 6.6.99-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: kkcmd kcm_tx_work Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x200 mm/kasan/report.c:466 kasan_report+0x117/0x150 mm/kasan/report.c:579 __lock_acquire+0xff/0x7c80 kernel/locking/lockdep.c:5005 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __lock_sock+0x156/0x2a0 net/core/sock.c:2965 lock_sock_nested+0x9f/0x100 net/core/sock.c:3515 lock_sock include/net/sock.h:1731 [inline] kcm_tx_work+0x31/0x180 net/kcm/kcmsock.c:716 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 6109: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509 sk_prot_alloc+0x57/0x210 net/core/sock.c:2088 sk_alloc+0x3a/0x360 net/core/sock.c:2147 kcm_clone net/kcm/kcmsock.c:1518 [inline] kcm_ioctl+0x215/0xff0 net/kcm/kcmsock.c:1563 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 6110: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3838 sk_prot_free net/core/sock.c:2128 [inline] __sk_destruct+0x485/0x620 net/core/sock.c:2222 kcm_release+0x524/0x5b0 net/kcm/kcmsock.c:1738 __sock_release net/socket.c:659 [inline] sock_close+0xbd/0x230 net/socket.c:1421 __fput+0x234/0x970 fs/file_table.c:384 __do_sys_close fs/open.c:1571 [inline] __se_sys_close+0x15f/0x220 fs/open.c:1556 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] kcm_unattach+0x861/0xe80 net/kcm/kcmsock.c:1427 kcm_unattach_ioctl net/kcm/kcmsock.c:1484 [inline] kcm_ioctl+0x791/0xff0 net/kcm/kcmsock.c:1551 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 kcm_attach net/kcm/kcmsock.c:1307 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1335 [inline] kcm_ioctl+0xe4f/0xff0 net/kcm/kcmsock.c:1541 sock_do_ioctl+0xd7/0x2f0 net/socket.c:1222 sock_ioctl+0x623/0x7a0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888077a015c0 which belongs to the cache KCM of size 1720 The buggy address is located 176 bytes inside of freed 1720-byte region [ffff888077a015c0, ffff888077a01c78) The buggy address belongs to the physical page: page:ffffea0001de8000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x77a00 head:ffffea0001de8000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802440ab01 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff88802c0063c0 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080110011 00000001ffffffff ffff88802440ab01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6100, tgid 6099 (syz.0.39), ts 112368068780, free_ts 112350455151 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x1b7/0x2e0 mm/slub.c:3509 sk_prot_alloc+0x57/0x210 net/core/sock.c:2088 sk_alloc+0x3a/0x360 net/core/sock.c:2147 kcm_create+0x100/0x570 net/kcm/kcmsock.c:1808 __sock_create+0x4a6/0x940 net/socket.c:1571 sock_create net/socket.c:1627 [inline] __sys_socket_create net/socket.c:1664 [inline] __sys_socket+0xd7/0x1a0 net/socket.c:1715 __do_sys_socket net/socket.c:1729 [inline] __se_sys_socket net/socket.c:1727 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1727 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2122 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2662 put_cpu_partial+0x17c/0x250 mm/slub.c:2738 __slab_free+0x31d/0x410 mm/slub.c:3686 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __vmalloc_area_node mm/vmalloc.c:3144 [inline] __vmalloc_node_range+0x59a/0x1320 mm/vmalloc.c:3339 __vmalloc_node mm/vmalloc.c:3404 [inline] vzalloc+0x79/0x90 mm/vmalloc.c:3477 __do_replace+0xa8/0x980 net/ipv4/netfilter/ip_tables.c:1046 do_replace net/ipv4/netfilter/ip_tables.c:1141 [inline] do_ipt_set_ctl+0xa06/0xcc0 net/ipv4/netfilter/ip_tables.c:1635 nf_setsockopt+0x263/0x280 net/netfilter/nf_sockopt.c:101 Memory state around the buggy address: ffff888077a01500: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff888077a01580: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff888077a01600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888077a01680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888077a01700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================