The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 47825b1646a6a9eca0f90baa3d4f98947c2add96 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2026010511-molasses-woven-927b@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 47825b1646a6a9eca0f90baa3d4f98947c2add96 Mon Sep 17 00:00:00 2001 From: Nicolas Dufresne nicolas.dufresne@collabora.com Date: Mon, 22 Sep 2025 14:43:39 -0400 Subject: [PATCH] media: verisilicon: Protect G2 HEVC decoder against invalid DPB index

Fix the Hantro G2 HEVC decoder so that we use DPB index 0 whenever a ninvalid index is received from user space. This protects the hardware from doing faulty memory access which then leads to bus errors.

To be noted that when a reference is missing, userspace such as GStreamer passes an invalid DPB index of 255. This issue was found by seeking to a CRA picture using GStreamer. The framework is currently missing the code to skip over RASL pictures placed after the CRA. This situation can also occur while doing live streaming over lossy transport.

Fixes: cb5dd5a0fa518 ("media: hantro: Introduce G2/HEVC decoder") Cc: stable@vger.kernel.org Reviewed-by: Benjamin Gaignard benjamin.gaignard@collabora.com Signed-off-by: Nicolas Dufresne nicolas.dufresne@collabora.com Signed-off-by: Hans Verkuil hverkuil+cisco@kernel.org

diff --git a/drivers/media/platform/verisilicon/hantro_g2_hevc_dec.c b/drivers/media/platform/verisilicon/hantro_g2_hevc_dec.c index f066636e56f9..e8c2e83379de 100644 --- a/drivers/media/platform/verisilicon/hantro_g2_hevc_dec.c +++ b/drivers/media/platform/verisilicon/hantro_g2_hevc_dec.c @@ -283,6 +283,15 @@ static void set_params(struct hantro_ctx *ctx) hantro_reg_write(vpu, &g2_apf_threshold, 8); }

+static u32 get_dpb_index(const struct v4l2_ctrl_hevc_decode_params *decode_params, + const u32 index) +{ + if (index > decode_params->num_active_dpb_entries) + return 0; + + return index; +} + static void set_ref_pic_list(struct hantro_ctx *ctx) { const struct hantro_hevc_dec_ctrls *ctrls = &ctx->hevc_dec.ctrls; @@ -355,8 +364,10 @@ static void set_ref_pic_list(struct hantro_ctx *ctx) list1[j++] = list1[i++];

for (i = 0; i < V4L2_HEVC_DPB_ENTRIES_NUM_MAX; i++) { - hantro_reg_write(vpu, &ref_pic_regs0[i], list0[i]); - hantro_reg_write(vpu, &ref_pic_regs1[i], list1[i]); + hantro_reg_write(vpu, &ref_pic_regs0[i], + get_dpb_index(decode_params, list0[i])); + hantro_reg_write(vpu, &ref_pic_regs1[i], + get_dpb_index(decode_params, list1[i])); } }