[ndctl PATCH v2 1/3] cxl/region: fix a dereferecnce after NULL check

[Vishal Verma <vishal.l.verma@intel.com>]

A NULL check in region_action() implies that 'decoder' might be NULL, but
later we dereference it during cxl_decoder_foreach(). The NULL check is
valid because it was the filter result being checked, however, while
doing this, the original 'decoder' variable was being clobbered.

Check the filter results independently of the original decoder variable.

Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 cxl/region.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/cxl/region.c b/cxl/region.c
index a30313c..334fcc2 100644
--- a/cxl/region.c
+++ b/cxl/region.c
@@ -686,9 +686,8 @@ static int region_action(int argc, const char **argv, struct cxl_ctx *ctx,
 			continue;
 
 		cxl_decoder_foreach (port, decoder) {
-			decoder = util_cxl_decoder_filter(decoder,
-							  param.root_decoder);
-			if (!decoder)
+			if (!util_cxl_decoder_filter(decoder,
+						     param.root_decoder))
 				continue;
 			rc = decoder_region_action(p, decoder, action, count);
 			if (rc)
-- 
2.37.2