CVE-2022-50269

In the Linux kernel, the following vulnerability has been resolved:

drm/vkms: Fix memory leak in vkms_init()

A memory leak was reported after the vkms module install failed.

unreferenced object 0xffff88810bc28520 (size 16): comm modprobe, pid 9662, jiffies 4298009455 (age 42.590s) hex dump (first 16 bytes): 01 01 00 64 81 88 ff ff 00 00 dc 0a 81 88 ff ff …d………… backtrace: [<00000000e7561ff8>] kmalloc_trace+0x27/0x60 [<000000000b1954a0>] 0xffffffffc45200a9 [<00000000abbf1da0>] do_one_initcall+0xd0/0x4f0 [<000000001505ee87>] do_init_module+0x1a4/0x680 [<00000000958079ad>] load_module+0x6249/0x7110 [<00000000117e4696>] __do_sys_finit_module+0x140/0x200 [<00000000f74b12d2>] do_syscall_64+0x35/0x80 [<000000008fc6fcde>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

The reason is that the vkms_init() returns without checking the return value of vkms_create(), and if the vkms_create() failed, the config allocated at the beginning of vkms_init() is leaked.

vkms_init() config = kmalloc(…) # config allocated … return vkms_create() # vkms_create failed and config is leaked

Fix this problem by checking return value of vkms_create() and free the config if error happened.

Affected Software

References

• https://git.kernel.org/stable/c/07ab77154d6fd2d67e465ab5ce30083709950f02
• https://git.kernel.org/stable/c/0d0b368b9d104b437e1f4850ae94bdb9a3601e89
• https://git.kernel.org/stable/c/bad13de764888b765ceaa4668893b52bd16653cc
• https://git.kernel.org/stable/c/bebd60ec3bf21062f103e32e6203c6daabdbd51b