Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: net: vlan: fix underflow for the real_dev refcnt Inject error before dev_hold(real_dev) in register_vlan_dev(), and execute the following testcase: ip link add dev dummy1 type dummy ip link add name dummy1.100 link dummy1 type vlan id 100 ip link del dev dummy1 When the dummy netdevice is removed, we will get a WARNING as following: ======================================================================= refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 2 PID: 0 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 and an endless loop of: ======================================================================= unregister_netdevice: waiting for dummy1 to become free. Usage count = -1073741824 That is because dev_put(real_dev) in vlan_dev_free() be called without dev_hold(real_dev) in register_vlan_dev(). It makes the refcnt of real_dev underflow. Move the dev_hold(real_dev) to vlan_dev_init() which is the call-back of ndo_init(). That makes dev_hold() and dev_put() for vlan's real_dev symmetrical.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 700602b662d7eaa816b1a3cb0abe7a85de358fd4 before 5e44178864b38dd70b877985abd7d86fdb95f27d; affected e04a7a84bb77f9cdf4475340fe931389bc72331c before 6e800ee43218a56acc93676bbb3d93b74779e555; affected 21032425c36ff85f16e72ca92193a8c401e4acd5 before f7fc72a508cf115c273a7a29350069def1041890; affected 563bcbae3ba233c275c244bfce2efe12938f5363 before 01d9cc2dea3fde3bad6d27f464eff463496e2b00; affected fca96b3f852a1b369b7b2844ce357cd689879934; affected 5.14.19 before 5.15 |
| Linux / Linux | affected 5.4.160 before 5.4.163; affected 5.10.80 before 5.10.83; affected 5.15.3 before 5.15.6 |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/5e44178864b38dd70b877985abd7d86fdb95f27d
- https://git.kernel.org/stable/c/6e800ee43218a56acc93676bbb3d93b74779e555
- https://git.kernel.org/stable/c/f7fc72a508cf115c273a7a29350069def1041890
- https://git.kernel.org/stable/c/01d9cc2dea3fde3bad6d27f464eff463496e2b00
ADP enrichment
No English description supplied.
No references supplied.
No English description supplied.