Jouni Hogander b8eb718348 net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject
kobject_init_and_add takes reference even when it fails. This has
to be given up by the caller in error handling. Otherwise memory
allocated by kobject_init_and_add is never freed. Originally found
by Syzkaller:

BUG: memory leak
unreferenced object 0xffff8880679f8b08 (size 8):
  comm "netdev_register", pid 269, jiffies 4294693094 (age 12.132s)
  hex dump (first 8 bytes):
    72 78 2d 30 00 36 20 d4                          rx-0.6 .
  backtrace:
    [<000000008c93818e>] __kmalloc_track_caller+0x16e/0x290
    [<000000001f2e4e49>] kvasprintf+0xb1/0x140
    [<000000007f313394>] kvasprintf_const+0x56/0x160
    [<00000000aeca11c8>] kobject_set_name_vargs+0x5b/0x140
    [<0000000073a0367c>] kobject_init_and_add+0xd8/0x170
    [<0000000088838e4b>] net_rx_queue_update_kobjects+0x152/0x560
    [<000000006be5f104>] netdev_register_kobject+0x210/0x380
    [<00000000e31dab9d>] register_netdevice+0xa1b/0xf00
    [<00000000f68b2465>] __tun_chr_ioctl+0x20d5/0x3dd0
    [<000000004c50599f>] tun_chr_ioctl+0x2f/0x40
    [<00000000bbd4c317>] do_vfs_ioctl+0x1c7/0x1510
    [<00000000d4c59e8f>] ksys_ioctl+0x99/0xb0
    [<00000000946aea81>] __x64_sys_ioctl+0x78/0xb0
    [<0000000038d946e5>] do_syscall_64+0x16f/0x580
    [<00000000e0aa5d8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<00000000285b3d1a>] 0xffffffffffffffff

Cc: David Miller <davem@davemloft.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-20 12:09:50 -08:00
2019-11-15 00:13:23 +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
Linux kernel source tree
Readme 8.6 GiB
Languages
C 97.1%
Assembly 1%
Shell 0.6%
Rust 0.4%
Python 0.4%
Other 0.3%