From 20aa934ace6917262ff579a73ec018d06a7bad1c Mon Sep 17 00:00:00 2001 From: Christian Hewitt Date: Wed, 24 Jun 2026 06:58:08 +0000 Subject: [PATCH] media: meson: vdec: fix NULL pointer deref in vdec_try_fmt_common When VIDIOC_TRY_FMT is called with an unsupported pixel format on the OUTPUT queue, vdec_try_fmt_common() falls back to V4L2_PIX_FMT_MPEG2. However, if a distro has locally patched MPEG2 support out (as it has been broken for some time) the platform format table does not contain MPEG2 so find_format() returns NULL and the subsequent dereference of fmt_out->max_width triggers a NULL pointer dereference. Fix this by falling back to the first format in the platform's format array instead of hardcoding V4L2_PIX_FMT_MPEG2. This is always valid since every platform defines at least one format. Fixes: 3e7f51bd9607 ("media: meson: add v4l2 m2m video decoder driver") Cc: stable@vger.kernel.org Signed-off-by: Christian Hewitt Reviewed-by: Nicolas Dufresne Signed-off-by: Nicolas Dufresne Signed-off-by: Hans Verkuil --- drivers/staging/media/meson/vdec/vdec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/media/meson/vdec/vdec.c b/drivers/staging/media/meson/vdec/vdec.c index a039d925c0fe..c18bf352b199 100644 --- a/drivers/staging/media/meson/vdec/vdec.c +++ b/drivers/staging/media/meson/vdec/vdec.c @@ -504,8 +504,8 @@ vdec_try_fmt_common(struct amvdec_session *sess, u32 size, case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: fmt_out = find_format(fmts, size, pixmp->pixelformat); if (!fmt_out) { - pixmp->pixelformat = V4L2_PIX_FMT_MPEG2; - fmt_out = find_format(fmts, size, pixmp->pixelformat); + pixmp->pixelformat = fmts[0].pixfmt; + fmt_out = &fmts[0]; } break; case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: