CVE-2026-53382

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.

Fix both the root cause (add error check in vidtv_mux_pid_ctx_init

for PMT PIDs) and add defensive NULL checks in vidtv_mux_push_si for

all vidtv_mux_get_pid_ctx() calls.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI

KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]

Workqueue: events vidtv_mux_tick

RIP: 0010:vidtv_psi_ts_psi_write_into+0x54a/0xbc0 drivers/media/test-drivers/vidtv/vidtv_psi.c:197

Call Trace:

<TASK>

vidtv_psi_table_header_write_into drivers/media/test-drivers/vidtv/vidtv_psi.c:799 [inline]

vidtv_psi_pmt_write_into+0x3b2/0xa70 drivers/media/test-drivers/vidtv/vidtv_psi.c:1231

vidtv_mux_push_si+0x932/0xe80 drivers/media/test-drivers/vidtv/vidtv_mux.c:196

vidtv_mux_tick+0xe9b/0x1480 drivers/media/test-drivers/vidtv/vidtv_mux.c:408