[PATCH] cleanup udevstart

I just wanted to terminate the snprintf() strings, cause I can see a
overflow with closed eyes after all the audit :)

But then I changed a bit more to bring it in line with the style of the
other files. I replaced the exec_udev() function with the one from
udevd, cause we don't need to read the stdout from udev.

Please have a look if it still works for you too and not
only for usernames with 3 characters :)

diff --git a/udevstart.c b/udevstart.c
index 867919972ad9273e1a60984f7d32e8b99e3fff1a..5c977b5ce65ab0ee92574391d188066814d1329a 100644 (file)
--- a/udevstart.c
+++ b/udevstart.c
@@ -27,7 +27,6 @@
 #include <stdio.h>
 #include <errno.h>
 #include <ctype.h>
-#include <signal.h>
 #include <dirent.h>
 #include <sys/wait.h>
 
@@ -47,133 +46,86 @@ void log_message(int level, const char *format, ...)
 #endif
 
 
-#define MAX_PATHLEN    1024
-#define SYSBLOCK       "/sys/block"
-#define SYSCLASS       "/sys/class"
+#define MAX_PATHLEN            1024
+#define SYSBLOCK               "/sys/block"
+#define SYSCLASS               "/sys/class"
+#define UDEV_BIN               "/sbin/udev"
 
-static int execute_udev(char *path, char *value, int len)
+static void udev_exec(const char *path, const char* subsystem)
 {
-       int retval;
-       int res;
-       int status;
-       int fds[2];
        pid_t pid;
-       int value_set = 0;
-       char buffer[255];
-       char *pos;
-
-       retval = pipe(fds);
-       if (retval != 0) {
-               dbg("pipe failed");
-               return -1;
-       }
+       char action[] = "ACTION=add";
+       char devpath[MAX_PATHLEN];
+       char nosleep[] = "UDEV_NO_SLEEP=1";
+       char *env[] = { action, devpath, nosleep, NULL };
+
+       snprintf(devpath, MAX_PATHLEN, "DEVPATH=%s", path);
+       devpath[MAX_PATHLEN-1] = '\0';
+
        pid = fork();
-       switch(pid) {
+       switch (pid) {
        case 0:
                /* child */
-               close(STDOUT_FILENO);
-
-               /* dup write side of pipe to STDOUT */
-               dup(fds[1]);
-
-               dbg("executing /sbin/udev '%s'", path);
-               retval = execl("/sbin/udev", "/sbin/udev", path, NULL);
-
-               info("execution of '%s' failed", path);
+               execle(UDEV_BIN, "udev", subsystem, NULL, env);
+               dbg("exec of child failed");
                exit(1);
+               break;
        case -1:
-               dbg("fork failed");
-               return -1;
+               dbg("fork of child failed");
+               break;
        default:
-               /* parent reads from fds[0] */
-               close(fds[1]);
-               retval = 0;
-               while (1) {
-                       res = read(fds[0], buffer, sizeof(buffer) - 1);
-                       if (res <= 0)
-                               break;
-                       buffer[res] = '\0';
-                       if (res > len) {
-                               dbg("result len %d too short", len);
-                               retval = -1;
-                       }
-                       if (value_set) {
-                               dbg("result value already set");
-                               retval = -1;
-                       } else {
-                               value_set = 1;
-                               strncpy(value, buffer, len);
-                               pos = value + strlen(value)-1;
-                               if (pos[0] == '\n')
-                                       pos[0] = '\0';
-                               dbg("result is '%s'", value);
-                       }
-               }
-               close(fds[0]);
-               res = wait(&status);
-               if (res < 0) {
-                       dbg("wait failed result %d", res);
-                       retval = -1;
-               }
-
-               if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) {
-                       dbg("exec program status 0x%x", status);
-                       retval = -1;
-               }
+               wait(NULL);
        }
-       return retval;
 }
 
 static int udev_scan(void)
 {
-       char           *devpath;
-       DIR            *dir;
-       struct dirent  *dent;
-       int             retval = -EINVAL;
-       char scratch[200];
+       char *devpath;
+       DIR *dir;
+       struct dirent *dent;
+       int retval = -EINVAL;
 
        devpath = "block";
        dir = opendir(SYSBLOCK);
-       if (dir) {
-               for (dent = readdir(dir); dent; dent = readdir(dir)) {
-                       char            dirname[MAX_PATHLEN];
-                       DIR            *dir2;
-                       struct dirent  *dent2;
-                       if ((strcmp(dent->d_name, ".") == 0)
-                           || (strcmp(dent->d_name, "..") == 0))
+       if (dir != NULL) {
+               for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                       char dirname[MAX_PATHLEN];
+                       DIR *dir2;
+                       struct dirent *dent2;
+
+                       if ((strcmp(dent->d_name, ".") == 0) ||
+                           (strcmp(dent->d_name, "..") == 0))
                                continue;
 
                        snprintf(dirname, MAX_PATHLEN, "/block/%s", dent->d_name);
-
-                       setenv("DEVPATH", dirname, 1);
-                       dbg("udev block, 'DEVPATH' = '%s'", dirname);
-                       execute_udev("block", scratch, sizeof(scratch));
+                       dirname[MAX_PATHLEN-1] = '\0';
+                       udev_exec(dirname, "block");
 
                        snprintf(dirname, MAX_PATHLEN, "%s/%s", SYSBLOCK, dent->d_name);
-
                        dir2 = opendir(dirname);
-                       if (dir2) {
-                               for (dent2 = readdir(dir2); dent2; dent2 = readdir(dir2)) {
-                                       char            dirname2[MAX_PATHLEN];
-                                       DIR            *dir3;
-                                       struct dirent  *dent3;
+                       if (dir2 != NULL) {
+                               for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
+                                       char dirname2[MAX_PATHLEN];
+                                       DIR *dir3;
+                                       struct dirent *dent3;
 
                                        if ((strcmp(dent2->d_name, ".") == 0) ||
                                            (strcmp(dent2->d_name, "..") == 0))
                                                continue;
 
                                        snprintf(dirname2, MAX_PATHLEN, "%s/%s", dirname, dent2->d_name);
+                                       dirname2[MAX_PATHLEN-1] = '\0';
 
                                        dir3 = opendir(dirname2);
-                                       if (dir3) {
-                                               for (dent3 = readdir(dir3); dent3; dent3 = readdir(dir3)) {
+                                       if (dir3 != NULL) {
+                                               for (dent3 = readdir(dir3); dent3 != NULL; dent3 = readdir(dir3)) {
                                                        char filename[MAX_PATHLEN];
 
                                                        if (strcmp(dent3->d_name, "dev") == 0) {
-                                                               snprintf(filename, MAX_PATHLEN, "/block/%s/%s", dent->d_name, dent2->d_name);
-                                                               setenv("DEVPATH", filename, 1);
-                                                               dbg("udev block, 'DEVPATH' = '%s'", filename);
-                                                               execute_udev("block", scratch, sizeof(scratch));
+                                                               snprintf(filename, MAX_PATHLEN, "/block/%s/%s",
+                                                                        dent->d_name, dent2->d_name);
+                                                               filename[MAX_PATHLEN-1] = '\0';
+                                                               udev_exec(filename, "block");
                                                        }
                                                }
                                        }
@@ -184,43 +136,42 @@ static int udev_scan(void)
 
        devpath = "class";
        dir = opendir(SYSCLASS);
-       if (dir) {
-               for (dent = readdir(dir); dent; dent = readdir(dir)) {
-                       char            dirname[MAX_PATHLEN];
-                       DIR            *dir2;
-                       struct dirent  *dent2;
-                       if ((strcmp(dent->d_name, ".") == 0)
-                           || (strcmp(dent->d_name, "..") == 0))
+       if (dir != NULL) {
+               for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                       char dirname[MAX_PATHLEN];
+                       DIR *dir2;
+                       struct dirent *dent2;
+
+                       if ((strcmp(dent->d_name, ".") == 0) ||
+                           (strcmp(dent->d_name, "..") == 0))
                                continue;
 
                        snprintf(dirname, MAX_PATHLEN, "%s/%s", SYSCLASS, dent->d_name);
-
+                       dirname[MAX_PATHLEN] = '\0';
                        dir2 = opendir(dirname);
-                       if (dir2) {
-                               for (dent2 = readdir(dir2); dent2; dent2 = readdir(dir2)) {
-                                       char            dirname2[MAX_PATHLEN];
-                                       DIR            *dir3;
-                                       struct dirent  *dent3;
+                       if (dir2 != NULL) {
+                               for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
+                                       char dirname2[MAX_PATHLEN-1];
+                                       DIR *dir3;
+                                       struct dirent *dent3;
 
-                                       if ((strcmp(dent2->d_name, ".") == 0) || (strcmp(dent2->d_name, "..") == 0))
+                                       if ((strcmp(dent2->d_name, ".") == 0) ||
+                                           (strcmp(dent2->d_name, "..") == 0))
                                                continue;
 
                                        snprintf(dirname2, MAX_PATHLEN, "%s/%s", dirname, dent2->d_name);
+                                       dirname2[MAX_PATHLEN-1] = '\0';
 
                                        dir3 = opendir(dirname2);
-                                       if (dir3) {
-                                               for (dent3 = readdir(dir3); dent3; dent3 = readdir(dir3)) {
-                                                       char
-                                                                       filename[MAX_PATHLEN];
+                                       if (dir3 != NULL) {
+                                               for (dent3 = readdir(dir3); dent3 != NULL; dent3 = readdir(dir3)) {
+                                                       char filename[MAX_PATHLEN];
 
                                                        if (strcmp(dent3->d_name, "dev") == 0) {
-                                                               snprintf
-                                                                   (filename,
-                                                                    MAX_PATHLEN,
-                                                                    "/class/%s/%s", dent->d_name, dent2->d_name);
-                                                               setenv("DEVPATH", filename, 1);
-                                                               dbg("udev '%s', 'DEVPATH' = '%s'", dent->d_name, filename);
-                                                               execute_udev(dent->d_name, scratch, sizeof(scratch));
+                                                               snprintf(filename, MAX_PATHLEN, "/class/%s/%s",
+                                                                        dent->d_name, dent2->d_name);
+                                                               filename[MAX_PATHLEN-1] = '\0';
+                                                               udev_exec(filename, dent->d_name);
                                                        }
                                                }
                                        }
@@ -240,8 +191,5 @@ int main(int argc, char **argv, char **envp)
 {
        init_logging("udevstart");
 
-       setenv("ACTION", "add", 1);
-       setenv("UDEV_NO_SLEEP", "1", 1);
-
        return udev_scan();
 }