From 33c9e18b09f4025ae635ef24bab8eab1a686a711 Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Sun, 17 Mar 2013 16:14:58 +0100 Subject: [PATCH] avfiltergraph: check for sws opts being non-NULL before using them. Avoid snprintfing a NULL pointer. CC: libav-stable@libav.org (cherry picked from commit 6e3c13a559e9ff300b5ca60e1d503e594d7f055c) Signed-off-by: Reinhard Tartler --- libavfilter/avfiltergraph.c | 7 ++++++- libavfilter/graphparser.c | 3 ++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/libavfilter/avfiltergraph.c b/libavfilter/avfiltergraph.c index af96807531..b7dce7576f 100644 --- a/libavfilter/avfiltergraph.c +++ b/libavfilter/avfiltergraph.c @@ -23,6 +23,7 @@ #include #include +#include "libavutil/avstring.h" #include "avfilter.h" #include "avfiltergraph.h" #include "internal.h" @@ -163,7 +164,11 @@ static int query_formats(AVFilterGraph *graph, AVClass *log_ctx) /* couldn't merge format lists. auto-insert scale filter */ snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d", scaler_count++); - snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts); + av_strlcpy(scale_args, "0:0", sizeof(scale_args)); + if (graph->scale_sws_opts) { + av_strlcat(scale_args, ":", sizeof(scale_args)); + av_strlcat(scale_args, graph->scale_sws_opts, sizeof(scale_args)); + } if ((ret = avfilter_graph_create_filter(&scale, avfilter_get_by_name("scale"), inst_name, scale_args, NULL, graph)) < 0) return ret; diff --git a/libavfilter/graphparser.c b/libavfilter/graphparser.c index 00fb57ad57..0678cd0b35 100644 --- a/libavfilter/graphparser.c +++ b/libavfilter/graphparser.c @@ -121,7 +121,8 @@ static int create_filter(AVFilterContext **filt_ctx, AVFilterGraph *ctx, int ind return ret; } - if (!strcmp(filt_name, "scale") && args && !strstr(args, "flags")) { + if (!strcmp(filt_name, "scale") && args && !strstr(args, "flags") && + ctx->scale_sws_opts) { snprintf(tmp_args, sizeof(tmp_args), "%s:%s", args, ctx->scale_sws_opts); args = tmp_args;