Advisory [CVE-2026-53382] fix NULL pointer dereference in vidtv_mux_push_si

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: fix NULL pointer dereference in vidtv_mux_push_si syzbot reported a general protection fault in vidtv_psi_ts_psi_write_into [1]. vidtv_mux_get_pid_ctx() can return NULL, but vidtv_mux_push_si() does not check for this before dereferencing the returned pointer to access the continuity counter.

This leads to a general protection fault when accessing a near-NULL address. The root cause is that vidtv_mux_pid_ctx_init() does not check the return value of vidtv_mux_create_pid_ctx_once() for PMT section PIDs.

If the allocation fails, the PID context is never created, but init returns success. The subsequent vidtv_mux_push_si() call then gets NULL from vidtv_mux_get_pid_ctx() and crashes.

This vulnerability occurs because the `vidtv_mux_push_si()` function does not properly handle a NULL return value from `vidtv_mux_get_pid_ctx()`, which can happen if a PID context fails to allocate during initialization.

An attacker could potentially trigger this NULL pointer dereference, leading to a general protection fault and causing a system crash, resulting in a denial of service. Red Hat severity: not rated.

Weakness: CWE-476. Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected.