tcb_(un)convert: Check for UID == 0 before performing.

Signed-off-by: Björn Esser <[email protected]>
openwall · Dec 22, 2024 · 237815f · 237815f
1 parent b6ce07b
commit 237815f
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Showing 4 changed files with 20 additions and 2 deletions.
diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,11 @@
+2024-12-22  Björn Esser  <besser82 at fedoraproject.org>
+
+	tcb_(un)convert: Check for UID == 0 before performing.
+	* progs/Makefile: Install tcb_(un)convert with standard
+	executable permissions.
+	* progs/tcb_convert.c (main): Check for UID == 0.
+	* progs/tcb_unconvert.c (main): Likewise.
+
 2024-12-20  Björn Esser  <besser82 at fedoraproject.org>
 
 	libnss_tcb: Disallow potentially-malicious user names in getspnam(3).

diff --git a/progs/Makefile b/progs/Makefile
@@ -30,8 +30,8 @@ install: install-common
 install-common:
 	$(MKDIR) -p -m 755 $(DESTDIR)$(SBINDIR)
 	$(MKDIR) -p -m 755 $(DESTDIR)$(MANDIR)/man8
-	$(INSTALL) -m 700 $(CONVERT) $(DESTDIR)$(SBINDIR)/
-	$(INSTALL) -m 700 $(UNCONVERT) $(DESTDIR)$(SBINDIR)/
+	$(INSTALL) -m 755 $(CONVERT) $(DESTDIR)$(SBINDIR)/
+	$(INSTALL) -m 755 $(UNCONVERT) $(DESTDIR)$(SBINDIR)/
 	$(INSTALL) -m 644 $(CONVERT).8 $(DESTDIR)$(MANDIR)/man8/
 	$(INSTALL) -m 644 $(UNCONVERT).8 $(DESTDIR)$(MANDIR)/man8/
 

diff --git a/progs/tcb_convert.c b/progs/tcb_convert.c
@@ -265,6 +265,11 @@ int main(void)
 {
 	int status;
 
+	if (getuid()) {
+		fprintf(stderr, "Only root can do this!\n");
+		return 1;
+	}
+
 	if (lckpwdf()) {
 		perror("lckpwdf");
 		return 1;

diff --git a/progs/tcb_unconvert.c b/progs/tcb_unconvert.c
@@ -222,6 +222,11 @@ int main(void)
 	gid_t sysgid;
 	int status;
 
+	if (getuid()) {
+		fprintf(stderr, "Only root can do this!\n");
+		return 1;
+	}
+
 	gr = getgrnam("sys");
 	if (!gr) {
 		fprintf(stderr, "\"sys\" group not found.\n");