From 535d677beabd4d6e06437c386ae80e41ae34f122 Mon Sep 17 00:00:00 2001 From: Günther Deschner Date: Mon, 9 Oct 2017 18:02:25 +0200 Subject: md-cache: avoid checking the xattr value buffer with string functions. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit xattrs may very well contain binary, non-text data with leading 0 values. Using strcmp for checking empty values is not the appropriate thing to do: In the best case, it might treat a binary xattr value starting with 0 from being cached (and hence also from being reported back with xattr). In the worst case, we might read beyond the end of a data blob that does contain any zero byte. We fix this by checking the length of the data blob and checking the first byte against 0 if the length is one. > Signed-off-by: Guenther Deschner > Pair-Programmed-With: Michael Adam > Change-Id: If723c465a630b8a37b6be58782a2724df7ac6b11 > BUG: 1476324 > Reviewed-on: https://review.gluster.org/17910 > Reviewed-by: Michael Adam > Smoke: Gluster Build System > Reviewed-by: Poornima G > Tested-by: Poornima G > CentOS-regression: Gluster Build System > (cherry picked from commit ab4ffdac9dec1867f2d9b33242179cf2b347319d) Change-Id: If723c465a630b8a37b6be58782a2724df7ac6b11 BUG: 1499892 Signed-off-by: Günther Deschner --- xlators/performance/md-cache/src/md-cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'xlators') diff --git a/xlators/performance/md-cache/src/md-cache.c b/xlators/performance/md-cache/src/md-cache.c index 71fcabab271..364210232cb 100644 --- a/xlators/performance/md-cache/src/md-cache.c +++ b/xlators/performance/md-cache/src/md-cache.c @@ -633,7 +633,7 @@ updatefn(dict_t *dict, char *key, data_t *value, void *data) * not update their cache if the value of a xattr is a 0 byte * data (i.e. ""). */ - if (!strcmp (value->data, "")) + if (value->len == 1 && value->data[0] == '\0') continue; if (dict_set(u->dict, key, value) < 0) { -- cgit