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Description: Fix parsing of lines longer than 2047 characters
If a line in /etc/hosts.{allow,deny} is longer than BUFLEN-1 (2047)
characters then len will be set to 1 at the end of the xgets() loop.
.
At the next iteration, fgets will be passed a buffer of length 1, so it
will only be able to read an empty string (the buffer must always have
space for the trailing NUL).
.
strlen(3) on the empty string will return 0, so len will not be modified
anymore and the last step will repeat forever.
.
To reproduce:
perl -e 'print "#sshd: " . ("127.0.0.1, " x 210) . "\n"' > hosts.deny
tcpdmatch -d test localhost
Author: Marco d'Itri <md@linux.it>
Bug-Debian: http://bugs.debian.org/596261
--- a/misc.c
+++ b/misc.c
@@ -45,6 +45,8 @@ FILE *fp;
}
ptr += got;
len -= got;
+ if (len == 1)
+ return(start);
ptr[0] = 0;
}
return (ptr > start ? start : 0);
--- a/hosts_access.c
+++ b/hosts_access.c
@@ -165,7 +165,9 @@ struct request_info *request;
while (match == NO && xgets(sv_list, sizeof(sv_list), fp) != 0) {
if (sv_list[strlen(sv_list) - 1] != '\n') {
tcpd_warn("missing newline or line too long");
- continue;
+ tcpd_warn("all the subsequent rules will be ignored");
+ match = ERR;
+ break;
}
if (sv_list[0] == '#' || sv_list[strspn(sv_list, " \t\r\n")] == 0)
continue;
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