================================================================== BUG: KASAN: use-after-free in __gtp_encap_destroy+0x194/0x1b0 drivers/net/gtp.c:359 Read of size 8 at addr ffff88807c0fabd0 by task syz-executor.0/9193 CPU: 1 PID: 9193 Comm: syz-executor.0 Not tainted 5.11.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230 __kasan_report mm/kasan/report.c:396 [inline] kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413 __gtp_encap_destroy+0x194/0x1b0 drivers/net/gtp.c:359 gtp_encap_destroy+0x16/0x20 drivers/net/gtp.c:373 udpv6_destroy_sock+0x1df/0x220 net/ipv6/udp.c:1609 sk_common_release+0x64/0x390 net/core/sock.c:3262 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:475 __sock_release+0xcd/0x280 net/socket.c:597 sock_close+0x18/0x20 net/socket.c:1256 __fput+0x283/0x920 fs/file_table.c:280 task_work_run+0xdd/0x190 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x465b09 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff77071e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd0fe4bf5f R14: 00007ff77071e300 R15: 0000000000022000 Allocated by task 9193: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:401 [inline] ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429 kmalloc_node include/linux/slab.h:575 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:587 kvmalloc include/linux/mm.h:781 [inline] kvzalloc include/linux/mm.h:789 [inline] alloc_netdev_mqs+0x97/0xeb0 net/core/dev.c:10475 rtnl_create_link+0x219/0xad0 net/core/rtnetlink.c:3171 __rtnl_newlink+0xf9e/0x16e0 net/core/rtnetlink.c:3433 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3491 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2345 ___sys_sendmsg+0xf3/0x170 net/socket.c:2399 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2432 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 9193: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:356 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362 kasan_slab_free include/linux/kasan.h:192 [inline] slab_free_hook mm/slub.c:1547 [inline] slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580 slab_free mm/slub.c:3143 [inline] kfree+0xdb/0x3b0 mm/slub.c:4125 kvfree+0x42/0x50 mm/util.c:616 netdev_freemem net/core/dev.c:10429 [inline] free_netdev+0x4a9/0x5e0 net/core/dev.c:10598 __rtnl_newlink+0x1487/0x16e0 net/core/rtnetlink.c:3447 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3491 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2345 ___sys_sendmsg+0xf3/0x170 net/socket.c:2399 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2432 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88807c0fa000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 3024 bytes inside of 4096-byte region [ffff88807c0fa000, ffff88807c0fb000) The buggy address belongs to the page: page:0000000083baee6e refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c0f8 head:0000000083baee6e order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c42140 raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807c0faa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c0fab00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c0fab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c0fac00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c0fac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================