diff options
| author | Yang Yingliang <yangyingliang@huawei.com> | 2020-06-16 09:39:21 +0000 |
|---|---|---|
| committer | Shohei Sakamoto <sakamotos@casio.co.jp> | 2020-07-27 14:19:07 +0900 |
| commit | 523edd4cab441457cd8378f5dcd824b228d04f0a (patch) | |
| tree | 4586d4b16baa1e9b32efcb6eac6e908f797c2efd | |
| parent | d7bed8be96e00ffbf05a7a1945e12602deb96005 (diff) | |
| download | exynos-523edd4cab441457cd8378f5dcd824b228d04f0a.tar.gz | |
net: fix memleak in register_netdevice()
[ Upstream commit 814152a89ed52c722ab92e9fbabcac3cb8a39245 ]
I got a memleak report when doing some fuzz test:
unreferenced object 0xffff888112584000 (size 13599):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 32 bytes):
74 61 70 30 00 00 00 00 00 00 00 00 00 00 00 00 tap0............
00 ee d9 19 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000002f60ba65>] __kmalloc_node+0x309/0x3a0
[<0000000075b211ec>] kvmalloc_node+0x7f/0xc0
[<00000000d3a97396>] alloc_netdev_mqs+0x76/0xfc0
[<00000000609c3655>] __tun_chr_ioctl+0x1456/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff888111845cc0 (size 8):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 8 bytes):
74 61 70 30 00 88 ff ff tap0....
backtrace:
[<000000004c159777>] kstrdup+0x35/0x70
[<00000000d8b496ad>] kstrdup_const+0x3d/0x50
[<00000000494e884a>] kvasprintf_const+0xf1/0x180
[<0000000097880a2b>] kobject_set_name_vargs+0x56/0x140
[<000000008fbdfc7b>] dev_set_name+0xab/0xe0
[<000000005b99e3b4>] netdev_register_kobject+0xc0/0x390
[<00000000602704fe>] register_netdevice+0xb61/0x1250
[<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff88811886d800 (size 512):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 32 bytes):
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
ff ff ff ff ff ff ff ff c0 66 3d a3 ff ff ff ff .........f=.....
backtrace:
[<0000000050315800>] device_add+0x61e/0x1950
[<0000000021008dfb>] netdev_register_kobject+0x17e/0x390
[<00000000602704fe>] register_netdevice+0xb61/0x1250
[<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
If call_netdevice_notifiers() failed, then rollback_registered()
calls netdev_unregister_kobject() which holds the kobject. The
reference cannot be put because the netdev won't be add to todo
list, so it will leads a memleak, we need put the reference to
avoid memleak.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/core/dev.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index b6fd0887c0bc..6019d7c674a9 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6839,6 +6839,13 @@ int register_netdevice(struct net_device *dev) rcu_barrier(); dev->reg_state = NETREG_UNREGISTERED; + /* We should put the kobject that hold in + * netdev_unregister_kobject(), otherwise + * the net device cannot be freed when + * driver calls free_netdev(), because the + * kobject is being hold. + */ + kobject_put(&dev->dev.kobj); } /* * Prevent userspace races by waiting until the network |