postgres.git / summary / log / commit / refs

commit    3e1a4c260ef29249f412f2fcaa66c898d8d0bd7c
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Fri Oct 16 15:59:13 2020 +0000
First released in: 14.0, 9.5.24, 9.6.20, 10.15, 11.10, 12.5, 13.1

    Add missing error check in pgcrypto/crypt-md5.c.
    
    In theory, the second px_find_digest call in px_crypt_md5 could fail
    even though the first one succeeded, since resource allocation is
    required.  Don't skip testing for a failure.  (If one did happen,
    the likely result would be a crash rather than clean recovery from
    an OOM failure.)
    
    The code's been like this all along, so back-patch to all supported
    branches.
    
    Daniel Gustafsson
    
    Discussion: https://postgr.es/m/AA8D6FE9-4AB2-41B4-98CB-AE64BA668C03@yesql.se


 contrib/pgcrypto/crypt-md5.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/contrib/pgcrypto/crypt-md5.c b/contrib/pgcrypto/crypt-md5.c
index 6a09d76989f..cb1b97d7786 100644
--- a/contrib/pgcrypto/crypt-md5.c
+++ b/contrib/pgcrypto/crypt-md5.c
@@ -65,11 +65,17 @@ px_crypt_md5(const char *pw, const char *salt, char *passwd, unsigned dstlen)
 	/* get the length of the true salt */
 	sl = ep - sp;
 
-	/* */
+	/* we need two PX_MD objects */
 	err = px_find_digest("md5", &ctx);
 	if (err)
 		return NULL;
 	err = px_find_digest("md5", &ctx1);
+	if (err)
+	{
+		/* this path is possible under low-memory circumstances */
+		px_md_free(ctx);
+		return NULL;
+	}
 
 	/* The password first, since that is what is most unknown */
 	px_md_update(ctx, (const uint8 *) pw, strlen(pw));


[parent: bc63c8704676]