From: syzbot <syzbot+d6fa74e3f19d6ee01e3a@syzkaller.appspotmail.com>
To: davem@davemloft.net, edumazet@google.com, horms@kernel.org,
kuba@kernel.org, linux-kernel@vger.kernel.org,
netdev@vger.kernel.org, pabeni@redhat.com,
syzkaller-bugs@googlegroups.com
Subject: [syzbot] [net?] memory leak in l2tp_tunnel_create (2)
Date: Fri, 07 Aug 2026 10:00:34 -0700 [thread overview]
Message-ID: <6a760f32.01d0871a.3a0d52.004f.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 0d8395707651 Merge tag 'soc-fixes-7.2-2' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16fc3c99580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ba7c2d1679fb08a2
dashboard link: https://syzkaller.appspot.com/bug?extid=d6fa74e3f19d6ee01e3a
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10268132580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=141697b9580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/42469bee3e3a/disk-0d839570.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7e97e8a3401c/vmlinux-0d839570.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9204877a302c/bzImage-0d839570.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d6fa74e3f19d6ee01e3a@syzkaller.appspotmail.com
BUG: memory leak
unreferenced object 0xffff88812fbbb200 (size 256):
comm "syz.0.17", pid 6072, jiffies 4294946752
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc ff56d525):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__kmalloc_cache_noprof+0x356/0x440 mm/slub.c:5485
_kmalloc_noprof include/linux/slab.h:988 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
l2tp_tunnel_create+0x55/0x130 net/l2tp/l2tp_core.c:1581
pppol2tp_tunnel_get+0x132/0x250 net/l2tp/l2tp_ppp.c:654
pppol2tp_connect+0x1f4/0x8d0 net/l2tp/l2tp_ppp.c:711
__sys_connect_file+0x7a/0xb0 net/socket.c:2135
__sys_connect+0xe1/0x110 net/socket.c:2154
__do_sys_connect net/socket.c:2160 [inline]
__se_sys_connect net/socket.c:2157 [inline]
__x64_sys_connect+0x1c/0x30 net/socket.c:2157
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888101d20b00 (size 1408):
comm "syz.1.18", pid 6073, jiffies 4294946753
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............
backtrace (crc 66f8ac40):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
kmem_cache_alloc_noprof+0x34f/0x440 mm/slub.c:4931
sk_prot_alloc+0x3e/0x1b0 net/core/sock.c:2246
sk_alloc+0x36/0x3d0 net/core/sock.c:2308
inet_create net/ipv4/af_inet.c:333 [inline]
inet_create+0x168/0x4b0 net/ipv4/af_inet.c:259
__sock_create+0x1a9/0x2d0 net/socket.c:1651
sock_create net/socket.c:1709 [inline]
__sys_socket_create net/socket.c:1746 [inline]
__sys_socket+0xb7/0x1a0 net/socket.c:1793
__do_sys_socket net/socket.c:1807 [inline]
__se_sys_socket net/socket.c:1805 [inline]
__x64_sys_socket+0x1b/0x30 net/socket.c:1805
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88812d56d7e0 (size 32):
comm "syz.1.18", pid 6073, jiffies 4294946753
hex dump (first 32 bytes):
f8 52 0a 00 81 88 ff ff 00 00 00 00 00 00 00 00 .R..............
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 42a7bc0e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x3bf/0x550 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
lsm_blob_alloc+0x4d/0x80 security/security.c:218
lsm_sock_alloc security/security.c:4478 [inline]
security_sk_alloc+0x2d/0x290 security/security.c:4494
sk_prot_alloc+0x8f/0x1b0 net/core/sock.c:2255
sk_alloc+0x36/0x3d0 net/core/sock.c:2308
inet_create net/ipv4/af_inet.c:333 [inline]
inet_create+0x168/0x4b0 net/ipv4/af_inet.c:259
__sock_create+0x1a9/0x2d0 net/socket.c:1651
sock_create net/socket.c:1709 [inline]
__sys_socket_create net/socket.c:1746 [inline]
__sys_socket+0xb7/0x1a0 net/socket.c:1793
__do_sys_socket net/socket.c:1807 [inline]
__se_sys_socket net/socket.c:1805 [inline]
__x64_sys_socket+0x1b/0x30 net/socket.c:1805
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88812d473880 (size 128):
comm "syz.1.18", pid 6073, jiffies 4294946753
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 0):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x3bf/0x550 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
udp_lib_init_sock include/net/udp.h:295 [inline]
udp_init_sock+0x88/0x120 net/ipv4/udp.c:1813
inet_create net/ipv4/af_inet.c:391 [inline]
inet_create+0x301/0x4b0 net/ipv4/af_inet.c:259
__sock_create+0x1a9/0x2d0 net/socket.c:1651
sock_create net/socket.c:1709 [inline]
__sys_socket_create net/socket.c:1746 [inline]
__sys_socket+0xb7/0x1a0 net/socket.c:1793
__do_sys_socket net/socket.c:1807 [inline]
__se_sys_socket net/socket.c:1805 [inline]
__x64_sys_socket+0x1b/0x30 net/socket.c:1805
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88812fbbf800 (size 256):
comm "syz.1.18", pid 6073, jiffies 4294946753
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 2ce433f4):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__kmalloc_cache_noprof+0x356/0x440 mm/slub.c:5485
_kmalloc_noprof include/linux/slab.h:988 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
l2tp_tunnel_create+0x55/0x130 net/l2tp/l2tp_core.c:1581
pppol2tp_tunnel_get+0x132/0x250 net/l2tp/l2tp_ppp.c:654
pppol2tp_connect+0x1f4/0x8d0 net/l2tp/l2tp_ppp.c:711
__sys_connect_file+0x7a/0xb0 net/socket.c:2135
__sys_connect+0xe1/0x110 net/socket.c:2154
__do_sys_connect net/socket.c:2160 [inline]
__se_sys_connect net/socket.c:2157 [inline]
__x64_sys_connect+0x1c/0x30 net/socket.c:2157
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff88812d747c00 (size 256):
comm "syz.0.24", pid 6076, jiffies 4294946754
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 8e7bd6):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4597 [inline]
slab_alloc_node mm/slub.c:4917 [inline]
__kmalloc_cache_noprof+0x356/0x440 mm/slub.c:5485
_kmalloc_noprof include/linux/slab.h:988 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
l2tp_tunnel_create+0x55/0x130 net/l2tp/l2tp_core.c:1581
pppol2tp_tunnel_get+0x132/0x250 net/l2tp/l2tp_ppp.c:654
pppol2tp_connect+0x1f4/0x8d0 net/l2tp/l2tp_ppp.c:711
__sys_connect_file+0x7a/0xb0 net/socket.c:2135
__sys_connect+0xe1/0x110 net/socket.c:2154
__do_sys_connect net/socket.c:2160 [inline]
__se_sys_connect net/socket.c:2157 [inline]
__x64_sys_connect+0x1c/0x30 net/socket.c:2157
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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If the report is already addressed, let syzbot know by replying with:
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#syz undup
reply other threads:[~2026-08-07 17:00 UTC|newest]
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