From: Alejandro Colomar <alx@kernel.org>
Date: Wed, 3 Jul 2024 01:21:10 +0000 (+0200)
Subject: lib/: Use READLINKNUL() instead of its pattern
X-Git-Tag: 4.17.0-rc1~40
X-Git-Url: http://git.ipfire.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=f8c7955bbbd086aa086d4b61f3a0b100befe4258;p=thirdparty%2Fshadow.git

lib/: Use READLINKNUL() instead of its pattern

Signed-off-by: Alejandro Colomar <alx@kernel.org>
---

diff --git a/lib/tcbfuncs.c b/lib/tcbfuncs.c
index 3dc2abd70..6971ebe84 100644
--- a/lib/tcbfuncs.c
+++ b/lib/tcbfuncs.c
@@ -19,12 +19,13 @@
 
 #include "defines.h"
 #include "prototypes.h"
+#include "fs/readlink/readlinknul.h"
 #include "getdef.h"
 #include "shadowio.h"
 #include "tcbfuncs.h"
-
 #include "shadowlog_internal.h"
 
+
 #define SHADOWTCB_HASH_BY 1000
 #define SHADOWTCB_LOCK_SUFFIX ".lock"
 
@@ -96,7 +97,6 @@ static /*@null@*/ char *shadowtcb_path_rel_existing (const char *name)
 	char *path, *rval;
 	struct stat st;
 	char link[8192];
-	ssize_t ret;
 
 	if (asprintf (&path, TCB_DIR "/%s", name) == -1) {
 		OUT_OF_MEMORY;
@@ -125,8 +125,7 @@ static /*@null@*/ char *shadowtcb_path_rel_existing (const char *name)
 		free (path);
 		return NULL;
 	}
-	ret = readlink (path, link, sizeof (link) - 1);
-	if (-1 == ret) {
+	if (READLINKNUL(path, link) == -1) {
 		fprintf (shadow_logfd,
 		         _("%s: Cannot read symbolic link %s: %s\n"),
 		         shadow_progname, path, strerror (errno));
@@ -134,14 +133,6 @@ static /*@null@*/ char *shadowtcb_path_rel_existing (const char *name)
 		return NULL;
 	}
 	free (path);
-	if ((size_t)ret >= sizeof(link) - 1) {
-		stpcpy(&link[sizeof(link) - 1], "");
-		fprintf (shadow_logfd,
-		         _("%s: Suspiciously long symlink: %s\n"),
-		         shadow_progname, link);
-		return NULL;
-	}
-	stpcpy(&link[ret], "");
 	rval = strdup (link);
 	if (NULL == rval) {
 		OUT_OF_MEMORY;
diff --git a/lib/user_busy.c b/lib/user_busy.c
index 8e80049e7..43cff5b07 100644
--- a/lib/user_busy.c
+++ b/lib/user_busy.c
@@ -21,6 +21,7 @@
 
 #include "atoi/getnum.h"
 #include "defines.h"
+#include "fs/readlink/readlinknul.h"
 #include "prototypes.h"
 #ifdef ENABLE_SUBIDS
 #include "subordinateio.h"
@@ -93,17 +94,16 @@ static int different_namespace (const char *sname)
 	/* 41: /proc/xxxxxxxxxx/task/xxxxxxxxxx/ns/user + \0 */
 	char     path[41];
 	char     buf[512], buf2[512];
-	ssize_t  llen1, llen2;
 
 	SNPRINTF(path, "/proc/%s/ns/user", sname);
 
-	if ((llen1 = readlink (path, buf, sizeof(buf))) == -1)
+	if (READLINKNUL(path, buf) == -1)
 		return 0;
 
-	if ((llen2 = readlink ("/proc/self/ns/user", buf2, sizeof(buf2))) == -1)
+	if (READLINKNUL("/proc/self/ns/user", buf2) == -1)
 		return 0;
 
-	if (llen1 == llen2 && memcmp (buf, buf2, llen1) == 0)
+	if (strcmp(buf, buf2) == 0)
 		return 0; /* same namespace */
 
 	return 1;