From: Karel Zak <kzak@redhat.com>
Date: Thu, 2 May 2024 08:07:04 +0000 (+0200)
Subject: wall: check sysconf() returnvalue
X-Git-Tag: v2.42-start~358
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3c92af3a93ca3b308e2017ca04082b81056ce248;p=thirdparty%2Futil-linux.git

wall: check sysconf() returnvalue

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/term-utils/wall.c b/term-utils/wall.c
index 4937bdc80..125fde438 100644
--- a/term-utils/wall.c
+++ b/term-utils/wall.c
@@ -136,10 +136,17 @@ static gid_t get_group_gid(const char *group)
 
 static struct group_workspace *init_group_workspace(const char *group)
 {
-	struct group_workspace *buf = xmalloc(sizeof(struct group_workspace));
+	struct group_workspace *buf;
+	long n;
+
+	n = sysconf(_SC_NGROUPS_MAX);
+	if (n < 0 || n > INT_MAX - 1)
+		return NULL;
+
+	buf = xmalloc(sizeof(struct group_workspace));
+	buf->ngroups = n + 1;	/* room for the primary gid */
 
 	buf->requested_group = get_group_gid(group);
-	buf->ngroups = sysconf(_SC_NGROUPS_MAX) + 1;  /* room for the primary gid */
 	buf->groups = xcalloc(buf->ngroups, sizeof(*buf->groups));
 
 	return buf;