syzbot


memory leak in nr_sendmsg

Status: upstream: reported C repro on 2025/11/28 22:38
Subsystems: hams
[Documentation on labels]
Reported-by: syzbot+d7abc36bbbb6d7d40b58@syzkaller.appspotmail.com
First crash: 5d00h, last: 5d00h
Discussions (3)
Title Replies (including bot) Last reply
[PATCH net] netrom: Fix memory leak in nr_sendmsg() 1 (1) 2025/11/29 04:13
[PATCH] net: netrom: fix memory leak in nr_output() 2 (2) 2025/11/29 04:01
[syzbot] [hams?] memory leak in nr_sendmsg 1 (4) 2025/11/29 02:36
Last patch testing requests (2)
Created Duration User Patch Repo Result
2025/11/29 01:39 42m kartikey406@gmail.com patch upstream OK log
2025/11/29 01:26 55m wangliang74@huawei.com patch upstream OK log

Sample crash report:
BUG: memory leak
unreferenced object 0xffff888129f35500 (size 240):
  comm "syz.0.17", pid 6119, jiffies 4294944652
  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 10 52 28 81 88 ff ff  ..........R(....
  backtrace (crc 1456a3e4):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4983 [inline]
    slab_alloc_node mm/slub.c:5288 [inline]
    kmem_cache_alloc_node_noprof+0x36f/0x5e0 mm/slub.c:5340
    __alloc_skb+0x203/0x240 net/core/skbuff.c:660
    alloc_skb include/linux/skbuff.h:1383 [inline]
    alloc_skb_with_frags+0x69/0x3f0 net/core/skbuff.c:6671
    sock_alloc_send_pskb+0x379/0x3e0 net/core/sock.c:2965
    sock_alloc_send_skb include/net/sock.h:1859 [inline]
    nr_sendmsg+0x287/0x450 net/netrom/af_netrom.c:1105
    sock_sendmsg_nosec net/socket.c:727 [inline]
    __sock_sendmsg net/socket.c:742 [inline]
    sock_write_iter+0x293/0x2a0 net/socket.c:1195
    new_sync_write fs/read_write.c:593 [inline]
    vfs_write+0x45d/0x710 fs/read_write.c:686
    ksys_write+0x143/0x170 fs/read_write.c:738
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881112c0000 (size 65536):
  comm "syz.0.17", pid 6119, jiffies 4294944652
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01  ................
    01 00 00 05 02 98 92 9c aa b0 40 02 00 00 00 00  ..........@.....
  backtrace (crc 75262837):
    ___kmalloc_large_node+0xc1/0x100 mm/slub.c:5604
    __kmalloc_large_node_noprof+0x18/0xa0 mm/slub.c:5622
    __do_kmalloc_node mm/slub.c:5638 [inline]
    __kmalloc_node_track_caller_noprof+0x412/0x6b0 mm/slub.c:5759
    kmalloc_reserve+0x96/0x180 net/core/skbuff.c:601
    __alloc_skb+0xd4/0x240 net/core/skbuff.c:670
    alloc_skb include/linux/skbuff.h:1383 [inline]
    alloc_skb_with_frags+0x69/0x3f0 net/core/skbuff.c:6671
    sock_alloc_send_pskb+0x379/0x3e0 net/core/sock.c:2965
    sock_alloc_send_skb include/net/sock.h:1859 [inline]
    nr_sendmsg+0x287/0x450 net/netrom/af_netrom.c:1105
    sock_sendmsg_nosec net/socket.c:727 [inline]
    __sock_sendmsg net/socket.c:742 [inline]
    sock_write_iter+0x293/0x2a0 net/socket.c:1195
    new_sync_write fs/read_write.c:593 [inline]
    vfs_write+0x45d/0x710 fs/read_write.c:686
    ksys_write+0x143/0x170 fs/read_write.c:738
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

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

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/24 22:32 upstream ac3fd01e4c1e bf6fe8fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-leak memory leak in nr_sendmsg
* Struck through repros no longer work on HEAD.