chiark / gitweb /
util_run_program(): fix possible buffer overflow #2
[elogind.git] / libudev / libudev-util-private.c
index fe8f29b3a89007e20b595a73693644e4b18484ca..e0670dbae5dcacb525e89db5e8c9eca5370f612d 100644 (file)
@@ -242,7 +242,8 @@ int util_resolve_subsys_kernel(struct udev *udev, const char *string,
 }
 
 int util_run_program(struct udev *udev, const char *command, char **envp,
-                    char *result, size_t ressize, size_t *reslen)
+                    char *result, size_t ressize, size_t *reslen,
+                    const sigset_t *sigmask)
 {
        int status;
        int outpipe[2] = {-1, -1};
@@ -250,7 +251,7 @@ int util_run_program(struct udev *udev, const char *command, char **envp,
        pid_t pid;
        char arg[UTIL_PATH_SIZE];
        char program[UTIL_PATH_SIZE];
-       char *argv[(sizeof(arg) / 2) + 1];
+       char *argv[((sizeof(arg) + 1) / 2) + 1];
        int devnull;
        int i;
        int err = 0;
@@ -268,10 +269,14 @@ int util_run_program(struct udev *udev, const char *command, char **envp,
                                /* do not separate quotes */
                                pos++;
                                argv[i] = strsep(&pos, "\'");
-                               while (pos != NULL && pos[0] == ' ')
-                                       pos++;
+                               if (pos != NULL)
+                                       while (pos[0] == ' ')
+                                               pos++;
                        } else {
                                argv[i] = strsep(&pos, " ");
+                               if (pos != NULL)
+                                       while (pos[0] == ' ')
+                                               pos++;
                        }
                        dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
                        i++;
@@ -330,6 +335,10 @@ int util_run_program(struct udev *udev, const char *command, char **envp,
                        dup2(errpipe[WRITE_END], STDERR_FILENO);
                        close(errpipe[WRITE_END]);
                }
+
+               if (sigmask)
+                       sigprocmask(SIG_BLOCK, sigmask, NULL);
+
                execve(argv[0], argv, envp);
                if (errno == ENOENT || errno == ENOTDIR) {
                        /* may be on a filesystem which is not mounted right now */