Handle invalid arguments to close()/fclose() better.

[coloredstderr/coloredstderr.git] / src / coloredstderr.c

diff --git a/src/coloredstderr.c b/src/coloredstderr.c
index f005c726446a35231dd6a4ebacce7367e461a27b..b7e71e17871d6f7c7411c4c922d48cfcb2530680 100644 (file)
--- a/src/coloredstderr.c
+++ b/src/coloredstderr.c
@@ -20,6 +20,8 @@
 
 #include <config.h>
 
+#include "compiler.h"
+
 /* Must be loaded before the following headers. */
 #include "ldpreload.h"
 
@@ -33,9 +35,17 @@
 #ifdef HAVE_ERROR_H
 # include <error.h>
 #endif
+#ifdef HAVE_STRUCT__IO_FILE__FILENO
+# include <libio.h>
+#endif
 
 /* Conflicting declaration in glibc. */
 #undef fwrite_unlocked
+/* These functions may be macros when compiling with hardening flags (fortify)
+ * which cause build failures when used in our hook macros below. Observed
+ * with Clang on Debian Wheezy. */
+#undef printf
+#undef fprintf
 
 
 /* Used by various functions, including debug(). */
@@ -51,8 +61,7 @@ static int force_write_to_non_tty;
 
 
 #include "constants.h"
-#include "compiler.h"
-#ifdef DEBUG
+#ifdef WARNING
 # include "debug.h"
 #endif
 
@@ -67,7 +76,7 @@ static int force_write_to_non_tty;
 /* Prevent inlining into hook functions because it may increase the number of
  * spilled registers unnecessarily. As it's not called very often accept the
  * additional call. */
-static int isatty_noinline(int fd) __noinline;
+static int isatty_noinline(int fd) noinline;
 static int isatty_noinline(int fd) {
     int saved_errno = errno;
     int result = isatty(fd);
@@ -137,10 +146,10 @@ static void init_pre_post_string(void) {
 
 /* Don't inline any of the pre/post functions. Keep the hook function as small
  * as possible for speed reasons. */
-static void handle_fd_pre(int fd) __noinline;
-static void handle_fd_post(int fd) __noinline;
-static void handle_file_pre(FILE *stream) __noinline;
-static void handle_file_post(FILE *stream) __noinline;
+static void handle_fd_pre(int fd) noinline;
+static void handle_fd_post(int fd) noinline;
+static void handle_file_pre(FILE *stream) noinline;
+static void handle_file_post(FILE *stream) noinline;
 
 static void handle_fd_pre(int fd) {
     int saved_errno = errno;
@@ -235,6 +244,10 @@ HOOK_FILE2(int, putc_unlocked, stream,
            int, c, FILE *, stream)
 HOOK_FILE1(int, putchar_unlocked, stdout,
            int, c)
+/* glibc defines (_IO_)putc_unlocked() to __overflow() in some cases. */
+#ifdef HAVE_STRUCT__IO_FILE__FILENO
+HOOK_FD2(int, __overflow, f->_fileno, _IO_FILE *, f, int, ch)
+#endif
 
 /* perror(3) */
 HOOK_VOID1(void, perror, STDERR_FILENO,
@@ -242,9 +255,9 @@ HOOK_VOID1(void, perror, STDERR_FILENO,
 
 /* error(3) */
 #ifdef HAVE_ERROR_H
-static void  error_vararg(int status, int errnum,
-                   char const *filename, unsigned int linenum,
-                   char const *format, va_list ap) {
+static void error_vararg(int status, int errnum,
+                         char const *filename, unsigned int linenum,
+                         char const *format, va_list ap) {
     static char const *last_filename;
     static unsigned int last_linenum;
 
@@ -383,14 +396,20 @@ static int (*real_close)(int);
 int close(int fd) {
     DLSYM_FUNCTION(real_close, "close");
 
-    close_fd(fd);
+    if (fd >= 0) {
+        close_fd(fd);
+    }
     return real_close(fd);
 }
 static int (*real_fclose)(FILE *);
 int fclose(FILE *fp) {
+    int fd;
+
     DLSYM_FUNCTION(real_fclose, "fclose");
 
-    close_fd(fileno(fp));
+    if (fp != NULL && (fd = fileno(fp)) >= 0) {
+        close_fd(fd);
+    }
     return real_fclose(fp);
 }
 
@@ -529,9 +548,19 @@ int execv(char const *path, char * const argv[]) {
 }
 
 static int (*real_execvp)(char const *path, char * const argv[]);
-int execvp(char const *path, char * const argv[]) {
+int execvp(char const *file, char * const argv[]) {
     DLSYM_FUNCTION(real_execvp, "execvp");
 
     update_environment();
-    return real_execvp(path, argv);
+    return real_execvp(file, argv);
 }
+
+#ifdef HAVE_EXECVPE
+extern char **environ;
+int execvpe(char const *file, char * const argv[], char * const envp[]) {
+    /* Fake the environment so we can reuse execvp(). */
+    environ = (char **)envp;
+
+    return execvp(file, argv);
+}
+#endif