Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
atm: clip: Fix memory leak of struct clip_vcc.
ioctl(ATMARP_MKIP) allocates struct clip_vcc and set it to vcc->user_back.
The code assumes that vcc_destroy_socket() passes NULL skb to vcc->push() when the socket is close()d, and then clip_push() frees clip_vcc.
However, ioctl(ATMARPD_CTRL) sets NULL to vcc->push() in atm_init_atmarp(), resulting in memory leak.
Let’s serialise two ioctl() by lock_sock() and check vcc->push() in atm_init_atmarp() to prevent memleak.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- kernel-uek @ 5.4.17 (+15 more)
In the Linux kernel, the following vulnerability has been resolved:
atm: clip: Fix memory leak of struct clip_vcc.
ioctl(ATMARP_MKIP) allocates struct clip_vcc and set it to vcc->user_back.
The code assumes that vcc_destroy_socket() passes NULL skb to vcc->push() when the socket is close()d, and then clip_push() frees clip_vcc.
However, ioctl(ATMARPD_CTRL) sets NULL to vcc->push() in atm_init_atmarp(), resulting in memory leak.
Let’s serialise two ioctl() by lock_sock() and check vcc->push() in atm_init_atmarp() to prevent memleak.