6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> [ Upstream commit 97c75ee5de060d271d80109b0c47cb6008439e5b ] The stateless HEVC decoder saves the instance pointer in the context regardless if the initialization worked or not. This caused a use after free, when the pointer is freed in case of a failure in the deinit function. Only store the instance pointer when the initialization was successful, to solve this issue. Hardware name: Acer Tomato (rev3 - 4) board (DT) pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] lr : vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] sp : ffff80008750bc20 x29: ffff80008750bc20 x28: ffff1299f6d70000 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 x23: ffff80008750bc98 x22: 000000000000a003 x21: ffffd45c4cfae000 x20: 0000000000000010 x19: ffff1299fd668310 x18: 000000000000001a x17: 000000040044ffff x16: ffffd45cb15dc648 x15: 0000000000000000 x14: ffff1299c08da1c0 x13: ffffd45cb1f87a10 x12: ffffd45cb2f5fe80 x11: 0000000000000001 x10: 0000000000001b30 x9 : ffffd45c4d12b488 x8 : 1fffe25339380d81 x7 : 0000000000000001 x6 : ffff1299c9c06c00 x5 : 0000000000000132 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000010 x1 : ffff80008750bc98 x0 : 0000000000000000 Call trace: vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] vpu_dec_deinit+0x1c/0x30 [mtk_vcodec_dec] vdec_hevc_slice_deinit+0x30/0x98 [mtk_vcodec_dec] vdec_if_deinit+0x38/0x68 [mtk_vcodec_dec] mtk_vcodec_dec_release+0x20/0x40 [mtk_vcodec_dec] fops_vcodec_release+0x64/0x118 [mtk_vcodec_dec] v4l2_release+0x7c/0x100 __fput+0x80/0x2d8 __fput_sync+0x58/0x70 __arm64_sys_close+0x40/0x90 invoke_syscall+0x50/0x128 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x38/0xd8 el0t_64_sync_handler+0xc0/0xc8 el0t_64_sync+0x1a8/0x1b0 Code: d503201f f9401660 b900127f b900227f (f9400400) Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> Fixes: 2674486aac7d ("media: mediatek: vcodec: support stateless hevc decoder") Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> Signed-off-by: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../mediatek/vcodec/decoder/vdec/vdec_hevc_req_multi_if.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_hevc_req_multi_if.c b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_hevc_req_multi_if.c index 06ed47df693bf..21836dd6ef85a 100644 --- a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_hevc_req_multi_if.c +++ b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_hevc_req_multi_if.c @@ -869,7 +869,6 @@ static int vdec_hevc_slice_init(struct mtk_vcodec_dec_ctx *ctx) inst->vpu.codec_type = ctx->current_codec; inst->vpu.capture_type = ctx->capture_fourcc; - ctx->drv_handle = inst; err = vpu_dec_init(&inst->vpu); if (err) { mtk_vdec_err(ctx, "vdec_hevc init err=%d", err); @@ -898,6 +897,7 @@ static int vdec_hevc_slice_init(struct mtk_vcodec_dec_ctx *ctx) mtk_vdec_debug(ctx, "lat hevc instance >> %p, codec_type = 0x%x", inst, inst->vpu.codec_type); + ctx->drv_handle = inst; return 0; error_free_inst: kfree(inst); -- 2.43.0