first pass at updating head branch to be to be the same as the SAMBA_2_0 branch

[kai/samba.git] / source3 / client / smbumount.c

diff --git a/source3/client/smbumount.c b/source3/client/smbumount.c
index bc8999d765e1a0880a2c1b5a9691f7710eedeeaf..dacf4ab67d08b28dab7e73a24c2c6300333801f2 100644 (file)
--- a/source3/client/smbumount.c
+++ b/source3/client/smbumount.c
@@ -23,20 +23,24 @@
 #undef SMB_IOC_GETMOUNTUID
 #define        SMB_IOC_GETMOUNTUID             _IOR('u', 1, __kernel_uid_t)
 
-static char *progname;
+#ifndef O_NOFOLLOW
+#define O_NOFOLLOW     0400000
+#endif
 
 static void
 usage(void)
 {
-        printf("usage: %s mount-point\n", progname);
+        printf("usage: smbumount mountpoint\n");
 }
 
 static int
 umount_ok(const char *mount_point)
 {
-        int fid = open(mount_point, O_RDONLY, 0);
+       /* we set O_NOFOLLOW to prevent users playing games with symlinks to
+          umount filesystems they don't own */
+        int fid = open(mount_point, O_RDONLY|O_NOFOLLOW, 0);
         __kernel_uid_t mount_uid;
-
+       
         if (fid == -1) {
                 fprintf(stderr, "Could not open %s: %s\n",
                         mount_point, strerror(errno));
@@ -49,7 +53,7 @@ umount_ok(const char *mount_point)
                 return -1;
         }
 
-        if (   (getuid() != 0)
+        if ((getuid() != 0)
             && (mount_uid != getuid())) {
                 fprintf(stderr, "You are not allowed to umount %s\n",
                         mount_point);
@@ -63,15 +67,14 @@ umount_ok(const char *mount_point)
 /* Make a canonical pathname from PATH.  Returns a freshly malloced string.
    It is up the *caller* to ensure that the PATH is sensible.  i.e.
    canonicalize ("/dev/fd0/.") returns "/dev/fd0" even though ``/dev/fd0/.''
-   is not a legal pathname for ``/dev/fd0.''  Anything we cannot parse
+   is not a legal pathname for ``/dev/fd0''  Anything we cannot parse
    we return unmodified.   */
-char *
+static char *
 canonicalize (char *path)
 {
        char *canonical = malloc (PATH_MAX + 1);
 
-       if (strlen(path) > PATH_MAX)
-       {
+       if (strlen(path) > PATH_MAX) {
                fprintf(stderr, "Mount point string too long\n");
                return NULL;
        }
@@ -91,22 +94,18 @@ int
 main(int argc, char *argv[])
 {
         int fd;
-
         char* mount_point;
-
         struct mntent *mnt;
         FILE* mtab;
         FILE* new_mtab;
 
-        progname = argv[0];
-
         if (argc != 2) {
                 usage();
                 exit(1);
         }
 
         if (geteuid() != 0) {
-                fprintf(stderr, "%s must be installed suid root\n", progname);
+                fprintf(stderr, "smbumount must be installed suid root\n");
                 exit(1);
         }