diff options
| -rw-r--r-- | mount/mount.c | 33 | ||||
| -rw-r--r-- | mount/umount.c | 22 | 
2 files changed, 36 insertions, 19 deletions
| diff --git a/mount/mount.c b/mount/mount.c index f92b23cb..23f27d67 100644 --- a/mount/mount.c +++ b/mount/mount.c @@ -80,8 +80,8 @@ static int list_with_volumelabel = 0;   */  static int mounttype = 0; -/* True if ruid != euid.  */ -static int suid = 0; +/* True if (ruid != euid) or (0 != ruid), i.e. only "user" mounts permitted.  */ +static int restricted = 1;  /* Contains the fd to read the passphrase from, if any. */  static int pfd = -1; @@ -774,12 +774,12 @@ guess_fstype_and_mount(const char *spec, const char *node, const char **types,  }  /* - * suid_check() + * restricted_check()   *	Die if the user is not allowed to do this.   */  static void -suid_check(const char *spec, const char *node, int *flags, char **user) { -  if (suid) { +restricted_check(const char *spec, const char *node, int *flags, char **user) { +  if (restricted) {        /*         * MS_OWNER: Allow owners to mount when fstab contains         * the owner option.  Note that this should never be used @@ -1109,7 +1109,7 @@ try_mount_one (const char *spec0, const char *node0, const char *types0,    if (mount_all && (flags & MS_NOAUTO))        goto out; -  suid_check(spec, node, &flags, &user); +  restricted_check(spec, node, &flags, &user);    /* The "mount -f" checks for for existing record in /etc/mtab (with     * regular non-fake mount this is usually done by kernel) @@ -1190,7 +1190,7 @@ mount_retry:    /* Mount failed, complain, but don't die.  */    if (types == 0) { -    if (suid) +    if (restricted)        error (_("mount: I could not determine the filesystem type, "  	       "and none was specified"));      else @@ -2027,11 +2027,20 @@ main(int argc, char *argv[]) {  		return print_all (types);  	} -	if (getuid () != geteuid ()) { -		suid = 1; -		if (types || options || readwrite || nomtab || mount_all || -		    fake || mounttype || (argc + specseen) != 1) -			die (EX_USAGE, _("mount: only root can do that")); +	{ +		const uid_t ruid = getuid(); +		const uid_t euid = geteuid(); + +		/* if we're really root and aren't running setuid */ +		if (((uid_t)0 == ruid) && (ruid == euid)) { +			restricted = 0; +		} +	} + +	if (restricted && +	    (types || options || readwrite || nomtab || mount_all || +	     fake || mounttype || (argc + specseen) != 1)) { +		die (EX_USAGE, _("mount: only root can do that"));  	}  	atexit(unlock_mtab); diff --git a/mount/umount.c b/mount/umount.c index 00745aed..738d05c3 100644 --- a/mount/umount.c +++ b/mount/umount.c @@ -74,8 +74,8 @@ int nomtab = 0;  /* Call losetup -d for each unmounted loop device. */  int delloop = 0; -/* True if ruid != euid.  */ -int suid = 0; +/* True if (ruid != euid) or (0 != ruid), i.e. only "user" umounts permitted. */ +int restricted = 1;  /* Last error message */  int complained_err = 0; @@ -477,7 +477,7 @@ umount_file (char *arg) {  	if (!mc && verbose)  		printf(_("Could not find %s in mtab\n"), file); -	if (suid) { +	if (restricted) {  		char *mtab_user = NULL;  		if (!mc) @@ -640,10 +640,18 @@ main (int argc, char *argv[]) {  			usage (stderr, 1);  		} -	if (getuid () != geteuid ()) { -		suid = 1; -		if (all || types || nomtab || force || remount) -			die (2, _("umount: only root can do that")); +	{ +		const uid_t ruid = getuid(); +		const uid_t euid = geteuid(); + +		/* if we're really root and aren't running setuid */ +		if (((uid_t)0 == ruid) && (ruid == euid)) { +			restricted = 0; +		} +	} + +	if (restricted && (all || types || nomtab || force || remount)) { +		die (2, _("umount: only root can do that"));  	}  	argc -= optind; | 
