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KASAN: slab-use-after-free Read in inet_shutdown

Status: closed as invalid on 2026/06/13 04:00
Subsystems: net
Labels: prio:normal
[Documentation on labels]
First crash: 43d, last: 43d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
16246745-a357-420d-ae60-1bfa25f4fab4 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ KASAN: slab-use-after-free Read in inet_shutdown 2026/05/18 11:27 2026/05/18 11:27 2026/05/18 12:23 55156e845761fb36809c4b3701a920dddce23332

			
		
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 KASAN: use-after-free Read in inet_shutdown (2) 19 4 1616d 1697d 0/1 auto-closed as invalid on 2022/05/17 02:29
linux-4.14 KASAN: use-after-free Read in inet_shutdown 19 12 1860d 1954d 0/1 auto-closed as invalid on 2021/09/14 22:13

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in inet_shutdown+0x2dd/0x390 net/ipv4/af_inet.c:916
Read of size 4 at addr ffff88807712b640 by task syz.1.31/5942

CPU: 0 UID: 0 PID: 5942 Comm: syz.1.31 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 inet_shutdown+0x2dd/0x390 net/ipv4/af_inet.c:916
 udp_tunnel_sock_release+0x6d/0x80 net/ipv4/udp_tunnel_core.c:197
 rxe_release_udp_tunnel drivers/infiniband/sw/rxe/rxe_net.c:294 [inline]
 rxe_sock_put drivers/infiniband/sw/rxe/rxe_net.c:639 [inline]
 rxe_net_del+0x198/0x280 drivers/infiniband/sw/rxe/rxe_net.c:664
 rxe_dellink+0x15/0x20 drivers/infiniband/sw/rxe/rxe.c:254
 nldev_dellink+0x304/0x3d0 drivers/infiniband/core/nldev.c:1849
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6d1/0xa10 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f147e79cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f147c9f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f147ea16090 RCX: 00007f147e79cdd9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000008
RBP: 00007f147e832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f147ea16128 R14: 00007f147ea16090 R15: 00007ffd31915e18
 </TASK>

Allocated by task 5876:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4569 [inline]
 slab_alloc_node mm/slub.c:4898 [inline]
 kmem_cache_alloc_lru_noprof+0x2b8/0x640 mm/slub.c:4917
 sock_alloc_inode+0x2c/0x190 net/socket.c:328
 alloc_inode+0x6a/0x1b0 fs/inode.c:345
 new_inode_pseudo include/linux/fs.h:3015 [inline]
 sock_alloc net/socket.c:697 [inline]
 __sock_create+0x12d/0x9d0 net/socket.c:1628
 udp_sock_create6+0xd6/0x6b0 net/ipv6/ip6_udp_tunnel.c:24
 udp_sock_create include/net/udp_tunnel.h:66 [inline]
 rxe_setup_udp_tunnel+0x129/0x7b0 drivers/infiniband/sw/rxe/rxe_net.c:277
 rxe_net_ipv6_init drivers/infiniband/sw/rxe/rxe_net.c:788 [inline]
 rxe_net_init+0x157/0x300 drivers/infiniband/sw/rxe/rxe_net.c:835
 rxe_newlink+0xd3/0x1c0 drivers/infiniband/sw/rxe/rxe.c:239
 nldev_newlink+0x5bc/0x650 drivers/infiniband/core/nldev.c:1812
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6d1/0xa10 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5639:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2689 [inline]
 slab_free mm/slub.c:6250 [inline]
 kmem_cache_free+0x182/0x650 mm/slub.c:6377
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
 handle_softirqs+0x22a/0x840 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
 __call_rcu_common kernel/rcu/tree.c:3131 [inline]
 call_rcu+0xee/0x890 kernel/rcu/tree.c:3251
 destroy_inode fs/inode.c:399 [inline]
 evict+0x95b/0xb10 fs/inode.c:865
 rxe_release_udp_tunnel drivers/infiniband/sw/rxe/rxe_net.c:294 [inline]
 rxe_sock_put drivers/infiniband/sw/rxe/rxe_net.c:639 [inline]
 rxe_net_del+0x198/0x280 drivers/infiniband/sw/rxe/rxe_net.c:664
 rxe_dellink+0x15/0x20 drivers/infiniband/sw/rxe/rxe.c:254
 nldev_dellink+0x304/0x3d0 drivers/infiniband/core/nldev.c:1849
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6d1/0xa10 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807712b600
 which belongs to the cache sock_inode_cache of size 1408
The buggy address is located 64 bytes inside of
 freed 1408-byte region [ffff88807712b600, ffff88807712bb80)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x77128
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88807570e601
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140af6c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800150015 00000000f5000000 ffff88807570e601
head: 00fff00000000040 ffff888140af6c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000800150015 00000000f5000000 ffff88807570e601
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_RECLAIMABLE|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5289, tgid 5289 (dhcpcd), ts 70453042001, free_ts 27828602122
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
 prep_new_page mm/page_alloc.c:1866 [inline]
 get_page_from_freelist+0x24ba/0x2540 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3467
 new_slab mm/slub.c:3525 [inline]
 refill_objects+0x339/0x3d0 mm/slub.c:7255
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x321/0x720 mm/slub.c:4651
 alloc_from_pcs mm/slub.c:4749 [inline]
 slab_alloc_node mm/slub.c:4883 [inline]
 kmem_cache_alloc_lru_noprof+0x37c/0x640 mm/slub.c:4917
 sock_alloc_inode+0x2c/0x190 net/socket.c:328
 alloc_inode+0x6a/0x1b0 fs/inode.c:345
 new_inode_pseudo include/linux/fs.h:3015 [inline]
 sock_alloc net/socket.c:697 [inline]
 __sock_create+0x12d/0x9d0 net/socket.c:1628
 sock_create net/socket.c:1722 [inline]
 __sys_socketpair+0x239/0x560 net/socket.c:1873
 __do_sys_socketpair net/socket.c:1922 [inline]
 __se_sys_socketpair net/socket.c:1919 [inline]
 __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1919
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
 __free_pages mm/page_alloc.c:5345 [inline]
 free_contig_range+0xb7/0x100 mm/page_alloc.c:7313
 destroy_args+0x4e5/0x570 mm/debug_vm_pgtable.c:993
 debug_vm_pgtable+0x3f8/0x410 mm/debug_vm_pgtable.c:1368
 do_one_initcall+0x250/0x870 init/main.c:1392
 do_initcall_level+0x104/0x190 init/main.c:1454
 do_initcalls+0x59/0xa0 init/main.c:1470
 kernel_init_freeable+0x2a6/0x3e0 init/main.c:1703
 kernel_init+0x1d/0x1d0 init/main.c:1593
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88807712b500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807712b580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807712b600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88807712b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807712b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/08 23:44 net-next ae5c3718aeec 0c5a8d8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in inet_shutdown
* Struck through repros no longer work on HEAD.