diff options
Diffstat (limited to 'mount/mount.c')
-rw-r--r-- | mount/mount.c | 33 |
1 files changed, 21 insertions, 12 deletions
diff --git a/mount/mount.c b/mount/mount.c index f92b23cba..23f27d676 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); |