LU-9245 utils: fix string copy handling within lgss_sk

Strings are not copied correctly when the fsname or nodemap field of
a shared key is replaced. Instead of being zero-terminated, the new
string may overlap the original if it is smaller.

Fixed by using the buffer length instead of the string length in
strncpy().

Change-Id: I17bb5aa0ca7c25b2545c17c6f23e69045730a547
Test-Parameters: trivial
Signed-off-by: Chris Hanna <hannac@iu.edu>
Reviewed-on: https://review.whamcloud.com/26165
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Kit Westneat <kit.westneat@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>

diff --git a/lustre/utils/gss/lgss_sk.c b/lustre/utils/gss/lgss_sk.c
index f7254d2..15ff3fc 100644 (file)
--- a/lustre/utils/gss/lgss_sk.c
+++ b/lustre/utils/gss/lgss_sk.c
@@ -550,7 +550,7 @@ int main(int argc, char **argv)
                generate_prime = type & SK_TYPE_CLIENT;
 
                strncpy(config->skc_nodemap, SK_DEFAULT_NODEMAP,
                generate_prime = type & SK_TYPE_CLIENT;
 
                strncpy(config->skc_nodemap, SK_DEFAULT_NODEMAP,

-                       strlen(SK_DEFAULT_NODEMAP));
+                       sizeof(config->skc_nodemap) - 1);

 
                if (!datafile)
                        datafile = "/dev/random";
 
                if (!datafile)
                        datafile = "/dev/random";


@@ -567,9 +567,11 @@ int main(int argc, char **argv)
        if (prime_bits != -1)
                config->skc_prime_bits = prime_bits;
        if (fsname)
        if (prime_bits != -1)
                config->skc_prime_bits = prime_bits;
        if (fsname)

-               strncpy(config->skc_fsname, fsname, strlen(fsname));
+               strncpy(config->skc_fsname, fsname,
+                       sizeof(config->skc_fsname) - 1);

        if (nodemap)
        if (nodemap)

-               strncpy(config->skc_nodemap, nodemap, strlen(nodemap));
+               strncpy(config->skc_nodemap, nodemap,
+                       sizeof(config->skc_nodemap) - 1);

        if (mgsnids && parse_mgsnids(mgsnids, config))
                goto error;
        if (sk_validate_config(config)) {
        if (mgsnids && parse_mgsnids(mgsnids, config))
                goto error;
        if (sk_validate_config(config)) {