Subject: [syzbot] [virt?] [net?] memory leak in __vsock_create (2)

From: syzbot <[email-masked]>
Date: Thu, 23 Apr 2026 19:02:33 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    1f318b96cc84 Linux 7.0-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14db28ba580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2c6ad6fefffa76b1
dashboard link: https://syzkaller.appspot.com/bug?extid=1b2c9c4a0f8708082678
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=12db28ba580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1215175a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d4ebd240d832/disk-1f318b96.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9548f49a7dec/vmlinux-1f318b96.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4e16f2bcfc7d/bzImage-1f318b96.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

2026/03/09 23:37:29 executed programs: 5
BUG: memory leak
unreferenced object 0xffff888128bb6d00 (size 1272):
  comm "kworker/0:1", pid 10, jiffies 4294944453
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    28 00 0b 40 00 00 00 00 00 00 00 00 00 00 00 00  (..@............
  backtrace (crc 31367ed9):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    kmem_cache_alloc_noprof+0x372/0x480 mm/slub.c:4876
    sk_prot_alloc+0x3e/0x1b0 net/core/sock.c:2239
    sk_alloc+0x36/0x460 net/core/sock.c:2301
    __vsock_create.constprop.0+0x38/0x2f0 net/vmw_vsock/af_vsock.c:893
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1557 [inline]
    virtio_transport_recv_pkt+0x855/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff8881141e93a0 (size 32):
  comm "kworker/0:1", pid 10, jiffies 4294944453
  hex dump (first 32 bytes):
    f8 6e 0a 00 81 88 ff ff 00 00 00 00 00 00 00 00  .n..............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc e7f5c8b3):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    __do_kmalloc_node mm/slub.c:5262 [inline]
    __kmalloc_noprof+0x3bd/0x560 mm/slub.c:5275
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    lsm_blob_alloc+0x4d/0x80 security/security.c:192
    lsm_sock_alloc security/security.c:4375 [inline]
    security_sk_alloc+0x2d/0x290 security/security.c:4391
    sk_prot_alloc+0x8f/0x1b0 net/core/sock.c:2248
    sk_alloc+0x36/0x460 net/core/sock.c:2301
    __vsock_create.constprop.0+0x38/0x2f0 net/vmw_vsock/af_vsock.c:893
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1557 [inline]
    virtio_transport_recv_pkt+0x855/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff888128bfa8a0 (size 96):
  comm "kworker/0:1", pid 10, jiffies 4294944453
  hex dump (first 32 bytes):
    00 6d bb 28 81 88 ff ff 00 00 00 00 00 00 00 00  .m.(............
    00 00 00 00 00 00 00 00 00 00 04 00 00 00 00 00  ................
  backtrace (crc 1fd60988):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    __kmalloc_cache_noprof+0x377/0x480 mm/slub.c:5378
    kmalloc_noprof include/linux/slab.h:950 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    virtio_transport_do_socket_init+0x2b/0xf0 net/vmw_vsock/virtio_transport_common.c:923
    vsock_assign_transport+0x309/0x3a0 net/vmw_vsock/af_vsock.c:642
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1575 [inline]
    virtio_transport_recv_pkt+0x8bc/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff888129e1e800 (size 1272):
  comm "kworker/1:3", pid 5832, jiffies 4294944454
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    28 00 0b 40 00 00 00 00 00 00 00 00 00 00 00 00  (..@............
  backtrace (crc 4bfb7c57):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    kmem_cache_alloc_noprof+0x372/0x480 mm/slub.c:4876
    sk_prot_alloc+0x3e/0x1b0 net/core/sock.c:2239
    sk_alloc+0x36/0x460 net/core/sock.c:2301
    __vsock_create.constprop.0+0x38/0x2f0 net/vmw_vsock/af_vsock.c:893
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1557 [inline]
    virtio_transport_recv_pkt+0x855/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff888114372e80 (size 32):
  comm "kworker/1:3", pid 5832, jiffies 4294944454
  hex dump (first 32 bytes):
    f8 6e 0a 00 81 88 ff ff 00 00 00 00 00 00 00 00  .n..............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc e7f5c8b3):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    __do_kmalloc_node mm/slub.c:5262 [inline]
    __kmalloc_noprof+0x3bd/0x560 mm/slub.c:5275
    kmalloc_noprof include/linux/slab.h:954 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    lsm_blob_alloc+0x4d/0x80 security/security.c:192
    lsm_sock_alloc security/security.c:4375 [inline]
    security_sk_alloc+0x2d/0x290 security/security.c:4391
    sk_prot_alloc+0x8f/0x1b0 net/core/sock.c:2248
    sk_alloc+0x36/0x460 net/core/sock.c:2301
    __vsock_create.constprop.0+0x38/0x2f0 net/vmw_vsock/af_vsock.c:893
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1557 [inline]
    virtio_transport_recv_pkt+0x855/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

BUG: memory leak
unreferenced object 0xffff8881054d0ea0 (size 96):
  comm "kworker/1:3", pid 5832, jiffies 4294944454
  hex dump (first 32 bytes):
    00 e8 e1 29 81 88 ff ff 00 00 00 00 00 00 00 00  ...)............
    00 00 00 00 00 00 00 00 00 00 04 00 00 00 00 00  ................
  backtrace (crc 72501265):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4547 [inline]
    slab_alloc_node mm/slub.c:4869 [inline]
    __kmalloc_cache_noprof+0x377/0x480 mm/slub.c:5378
    kmalloc_noprof include/linux/slab.h:950 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    virtio_transport_do_socket_init+0x2b/0xf0 net/vmw_vsock/virtio_transport_common.c:923
    vsock_assign_transport+0x309/0x3a0 net/vmw_vsock/af_vsock.c:642
    virtio_transport_recv_listen net/vmw_vsock/virtio_transport_common.c:1575 [inline]
    virtio_transport_recv_pkt+0x8bc/0xfc0 net/vmw_vsock/virtio_transport_common.c:1685
    vsock_loopback_work+0x104/0x140 net/vmw_vsock/vsock_loopback.c:142
    process_one_work+0x26c/0x5d0 kernel/workqueue.c:3275
    process_scheduled_works kernel/workqueue.c:3358 [inline]
    worker_thread+0x243/0x490 kernel/workqueue.c:3439
    kthread+0x14e/0x1a0 kernel/kthread.c:436
    ret_from_fork+0x23c/0x4b0 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF

---
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