utils-std

commit: 04a855e7c02241321787e07ad41870ac484b79f0
parent 7c36b3ccf8480f9c0244f5f4658a9b9b95638286
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Mon,  2 Sep 2024 19:18:42 +0200

cmd/pathchk: Fix off-by-one due to PATH_MAX including terminating NULL

Diffstat:
M
cmd/pathchk.c
9
++++++---
M
test-cmd/pathchk.t
4
++--

2 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/cmd/pathchk.c b/cmd/pathchk.c
@@ -40,7 +40,7 @@ int
 main(int argc, char *argv[])
 {
 	bool opt_P = false, opt_p = false;
-	size_t path_max = PATH_MAX;
+	size_t path_max = PATH_MAX - 1;
 	size_t name_max = NAME_MAX;
 
 	int c = -1;
@@ -53,7 +53,7 @@ main(int argc, char *argv[])
 			break;
 		case 'p':
 			opt_p = true;
-			path_max = _POSIX_PATH_MAX;
+			path_max = _POSIX_PATH_MAX - 1;
 			name_max = _POSIX_NAME_MAX;
 			break;
 		case ':':
@@ -89,6 +89,7 @@ main(int argc, char *argv[])
 			err = 1;
 		}
 
+		// PATH_MAX includes terminating NULL
 		if(len > path_max)
 		{
 			fprintf(stderr,
@@ -108,6 +109,8 @@ main(int argc, char *argv[])
 				fprintf(stderr, "pathchk: Path component starts with an hyphen: %s\n", p);
 				err = 1;
 			}
+
+			// NAME_MAX doesn't includes terminating NULL
 			size_t name_len = strlen(p);
 			if(name_len > name_max)
 			{
@@ -126,7 +129,7 @@ main(int argc, char *argv[])
 			if(access(path, F_OK) < 0 && errno != ENOENT)
 			{
 				fprintf(stderr,
-				        "pathchk: Error checking while checking '%s' against filesystem: %s\n",
+				        "pathchk: Error while checking '%s' against filesystem: %s\n",
 				        path,
 				        strerror(errno));
 				errno = 0;
diff --git a/test-cmd/pathchk.t b/test-cmd/pathchk.t
@@ -24,8 +24,8 @@ Thanks glibc for the broken getconf
   pathchk: Path \([0-9]+ octets\) is over the maximum size \([0-9]+ octets\): s/+ (re)
   [1]
 
-  $ pathchk -p "$(printf "%*s" "${POSIX_PATH_MAX}" | tr ' ' /)"
-  $ pathchk -p "$(printf "s%*s" "${POSIX_PATH_MAX}" | tr ' ' /)"
+  $ pathchk -p "$(printf "%*s" "$(( ${POSIX_PATH_MAX} - 1 ))" | tr ' ' /)"
+  $ pathchk -p "$(printf "s%*s" "$(( ${POSIX_PATH_MAX} - 1 ))" | tr ' ' /)"
   pathchk: Path \([0-9]+ octets\) is over the maximum size \([0-9]+ octets\): s/+ (re)
   [1]