================================================================== BUG: KASAN: slab-out-of-bounds in decode_session6 net/xfrm/xfrm_policy.c:3494 [inline] BUG: KASAN: slab-out-of-bounds in __xfrm_decode_session+0x18d7/0x20a0 net/xfrm/xfrm_policy.c:3600 Read of size 1 at addr ffff888023d5d5af by task syz.0.17/6660 CPU: 0 PID: 6660 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 decode_session6 net/xfrm/xfrm_policy.c:3494 [inline] __xfrm_decode_session+0x18d7/0x20a0 net/xfrm/xfrm_policy.c:3600 xfrm_decode_session_reverse include/net/xfrm.h:1237 [inline] icmpv6_route_lookup+0x442/0x600 net/ipv6/icmp.c:392 icmp6_send+0x11a2/0x1b40 net/ipv6/icmp.c:604 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x3b/0x4c0 net/ipv6/route.c:2835 dst_link_failure include/net/dst.h:437 [inline] ip6_tnl_xmit+0xe8b/0x2a80 net/ipv6/ip6_tunnel.c:1282 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1398 [inline] ip6_tnl_start_xmit+0xc6c/0x11c0 net/ipv6/ip6_tunnel.c:1446 __netdev_start_xmit include/linux/netdevice.h:4943 [inline] netdev_start_xmit include/linux/netdevice.h:4957 [inline] xmit_one net/core/dev.c:3632 [inline] dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648 sch_direct_xmit+0x25e/0x4c0 net/sched/sch_generic.c:345 qdisc_restart net/sched/sch_generic.c:410 [inline] __qdisc_run+0xa56/0x1500 net/sched/sch_generic.c:418 __dev_xmit_skb net/core/dev.c:3932 [inline] __dev_queue_xmit+0x10ad/0x3660 net/core/dev.c:4404 neigh_output include/net/neighbour.h:543 [inline] ip6_finish_output2+0xe3d/0x1630 net/ipv6/ip6_output.c:141 ip6_fragment+0x1535/0x1fd0 net/ipv6/ip6_output.c:1023 dst_output include/net/dst.h:467 [inline] NF_HOOK include/linux/netfilter.h:304 [inline] ip6_xmit+0x10f1/0x1890 net/ipv6/ip6_output.c:360 sctp_v6_xmit+0x9a4/0x1200 net/sctp/ipv6.c:250 sctp_packet_transmit+0x247d/0x2a30 net/sctp/output.c:653 sctp_packet_singleton+0x235/0x340 net/sctp/outqueue.c:783 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline] sctp_outq_flush+0x50e/0x3120 net/sctp/outqueue.c:1212 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x533b/0x5a60 net/sctp/sm_sideeffect.c:1169 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73 sctp_sendmsg_to_asoc+0x10a6/0x1830 net/sctp/socket.c:1839 sctp_sendmsg+0x1b83/0x28c0 net/sctp/socket.c:2029 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2200 __do_sys_sendto net/socket.c:2212 [inline] __se_sys_sendto net/socket.c:2208 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2208 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8d0279c799 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:00007f8d036bd028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f8d02a15fa0 RCX: 00007f8d0279c799 RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000005 RBP: 00007f8d02832c99 R08: 0000200000000080 R09: 000000000000001c R10: 0000000000000051 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8d02a16038 R14: 00007f8d02a15fa0 R15: 00007ffd01fc6f58 Allocated by task 1: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc_node include/linux/slab.h:616 [inline] kzalloc_node include/linux/slab.h:732 [inline] alloc_worker kernel/workqueue.c:2091 [inline] init_rescuer+0x91/0x2d0 kernel/workqueue.c:4724 alloc_workqueue+0x10bf/0x13d0 kernel/workqueue.c:4804 mlx4_init+0x47/0xb0 drivers/net/ethernet/mellanox/mlx4/main.c:4565 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 kernel_init+0x1d/0x1c0 init/main.c:1455 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff888023d5d500 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 7 bytes to the right of allocated 168-byte region [ffff888023d5d500, ffff888023d5d5a8) The buggy address belongs to the physical page: page:ffffea00008f5740 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23d5d anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c41a00 ffffea000096afc0 dead000000000005 raw: 0000000000000000 0000000000100010 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 1, tgid 1 (swapper/0), ts 8059292140, free_ts 8055186014 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] call_usermodehelper_setup+0x8e/0x260 kernel/umh.c:363 kobject_uevent_env+0x65d/0x8b0 lib/kobject_uevent.c:629 driver_register+0x2d4/0x310 drivers/base/driver.c:254 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 vfree+0x1a6/0x320 mm/vmalloc.c:2868 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:2788 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 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 Memory state around the buggy address: ffff888023d5d480: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888023d5d500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888023d5d580: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888023d5d600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023d5d680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================