cmdutils: remove the current working directory from the DLL search path on win32

Reviewed-by: Matt Oliver <protogonoi@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 3bf142c77337814458ed8e036796934032d9837f)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

6 files changed, 22 insertions, 0 deletions

diff --git a/cmdutils.c b/cmdutils.c
index 3543edd0cb..bb4f49a7ba 100644
--- a/cmdutils.c
+++ b/cmdutils.c
@@ -106,6 +106,15 @@ static void log_callback_report(void *ptr, int level, const char *fmt, va_list v
     }
 }
 
+void init_dynload(void)
+{
+#ifdef _WIN32
+    /* Calling SetDllDirectory with the empty string (but not NULL) removes the
+     * current working directory from the DLL search path as a security pre-caution. */
+    SetDllDirectory("");
+#endif
+}
+
 static void (*program_exit)(int ret);
 
 void register_exit(void (*cb)(int ret))
diff --git a/cmdutils.h b/cmdutils.h
index 7f3db2af1a..e5ea45bfb0 100644
--- a/cmdutils.h
+++ b/cmdutils.h
@@ -62,6 +62,11 @@ void register_exit(void (*cb)(int ret));
 void exit_program(int ret) av_noreturn;
 
 /**
+ * Initialize dynamic library loading
+ */
+void init_dynload(void);
+
+/**
  * Initialize the cmdutils option system, in particular
  * allocate the *_opts contexts.
  */
diff --git a/ffmpeg.c b/ffmpeg.c
index 602cbfa45d..2887e91d1a 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -4118,6 +4118,8 @@ int main(int argc, char **argv)
     int ret;
     int64_t ti;
 
+    init_dynload();
+
     register_exit(ffmpeg_cleanup);
 
     setvbuf(stderr,NULL,_IONBF,0); /* win32 runtime needs this */
diff --git a/ffplay.c b/ffplay.c
index 17327b036b..76d8fc8f2f 100644
--- a/ffplay.c
+++ b/ffplay.c
@@ -3684,6 +3684,8 @@ int main(int argc, char **argv)
     VideoState *is;
     char dummy_videodriver[] = "SDL_VIDEODRIVER=dummy";
 
+    init_dynload();
+
     av_log_set_flags(AV_LOG_SKIP_REPEATED);
     parse_loglevel(argc, argv, options);
 
diff --git a/ffprobe.c b/ffprobe.c
index 3e5324e36b..ed8babf784 100644
--- a/ffprobe.c
+++ b/ffprobe.c
@@ -3142,6 +3142,8 @@ int main(int argc, char **argv)
     char *w_name = NULL, *w_args = NULL;
     int ret, i;
 
+    init_dynload();
+
     av_log_set_flags(AV_LOG_SKIP_REPEATED);
     register_exit(ffprobe_cleanup);
 
diff --git a/ffserver.c b/ffserver.c
index 8b6e441513..822e729441 100644
--- a/ffserver.c
+++ b/ffserver.c
@@ -3817,6 +3817,8 @@ int main(int argc, char **argv)
     struct sigaction sigact = { { 0 } };
     int ret = 0;
 
+    init_dynload();
+
     config.filename = av_strdup("/etc/ffserver.conf");
 
     parse_loglevel(argc, argv, options);