Wang Liang 156a0f6341 netrom: Fix memory leak in nr_sendmsg()
[ Upstream commit 613d12dd794e078be8ff3cf6b62a6b9acf7f4619 ]

syzbot reported a memory leak [1].

When function sock_alloc_send_skb() return NULL in nr_output(), the
original skb is not freed, which was allocated in nr_sendmsg(). Fix this
by freeing it before return.

[1]
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

Reported-by: syzbot+d7abc36bbbb6d7d40b58@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d7abc36bbbb6d7d40b58
Tested-by: syzbot+d7abc36bbbb6d7d40b58@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20251129041315.1550766-1-wangliang74@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11 15:21:45 +01:00
2026-01-11 15:21:44 +01:00
2022-09-28 09:02:20 +02:00
2025-12-07 06:18:54 +09:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%