================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x106/0x7d10 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff888055a7cbb0 by task gfs2_quotad/4495 CPU: 0 PID: 4495 Comm: gfs2_quotad Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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 __lock_acquire+0x106/0x7d10 kernel/locking/lockdep.c:4919 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 finish_wait+0xb8/0x1d0 kernel/sched/wait.c:410 gfs2_quotad+0x4f3/0x680 fs/gfs2/quota.c:1579 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 4742: 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+0xae/0x230 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1303 [inline] nlmsg_new include/net/netlink.h:991 [inline] genlmsg_new include/net/genetlink.h:431 [inline] seg6_genl_get_tunsrc+0x59/0x5c0 net/ipv6/seg6.c:272 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:756 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0x604/0x790 net/netlink/genetlink.c:850 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5be/0x970 net/socket.c:2518 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572 __sys_sendmsg net/socket.c:2601 [inline] __do_sys_sendmsg net/socket.c:2610 [inline] __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608 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 Freed by task 4742: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 skb_free_head net/core/skbuff.c:762 [inline] pskb_expand_head+0x3c4/0x12a0 net/core/skbuff.c:1880 netlink_trim+0x180/0x220 net/netlink/af_netlink.c:1299 netlink_unicast+0x62/0x8d0 net/netlink/af_netlink.c:1334 nlmsg_unicast include/net/netlink.h:1088 [inline] genlmsg_unicast include/net/genetlink.h:373 [inline] genlmsg_reply include/net/genetlink.h:383 [inline] seg6_genl_get_tunsrc+0x50b/0x5c0 net/ipv6/seg6.c:290 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:756 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0x604/0x790 net/netlink/genetlink.c:850 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5be/0x970 net/socket.c:2518 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572 __sys_sendmsg net/socket.c:2601 [inline] __do_sys_sendmsg net/socket.c:2610 [inline] __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608 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 ffff888055a7c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2992 bytes inside of 8192-byte region [ffff888055a7c000, ffff888055a7e000) The buggy address belongs to the physical page: page:ffffea0001569e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55a78 head:ffffea0001569e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001df2800 dead000000000006 ffff888017442280 raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4277, tgid 4277 (syz-executor), ts 82569976839, free_ts 24239424994 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x6c/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvmalloc_array include/linux/slab.h:734 [inline] __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:471 [inline] ptr_ring_init include/linux/ptr_ring.h:489 [inline] skb_array_init include/linux/skb_array.h:182 [inline] pfifo_fast_init+0x35f/0x6a0 net/sched/sch_generic.c:870 qdisc_create_dflt+0x11a/0x4b0 net/sched/sch_generic.c:1019 attach_one_default_qdisc net/sched/sch_generic.c:1176 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2465 [inline] attach_default_qdiscs net/sched/sch_generic.c:1194 [inline] dev_activate+0x393/0x11a0 net/sched/sch_generic.c:1253 __dev_open+0x343/0x430 net/core/dev.c:1510 __dev_change_flags+0x20d/0x6a0 net/core/dev.c:8664 dev_change_flags+0x82/0x1a0 net/core/dev.c:8735 do_setlink+0xba1/0x3e60 net/core/rtnetlink.c:2833 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 free_contig_range+0x9d/0x150 mm/page_alloc.c:9625 destroy_args+0xf0/0xa0a mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x26a/0x840 init/main.c:1310 do_initcall_level+0x137/0x1e4 init/main.c:1383 do_initcalls+0x4b/0x8a init/main.c:1399 kernel_init_freeable+0x415/0x5be init/main.c:1638 kernel_init+0x19/0x1b0 init/main.c:1526 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888055a7ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055a7cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888055a7cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888055a7cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055a7cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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