[PATCH v2] ethdev: fix pointer check in GENEVE and RAW flow copy

[Denis Lyulin]

When rte_flow_conv_item_spec() is called from rte_flow_conv_pattern(),
the spec, last and mask pointers are checked separately. If the API
is used incorrectly, the spec pointer may be NULL while last and mask
may be valid pointers. Also call of rte_flow_conv() with
RTE_FLOW_CONV_OP_ITEM_MASK and item->spec == NULL may lead to the
same problem.

In rte_flow_conv_item_spec() for GENVE_OPT and RAW item types the spec
pointer is used even if the function is called to copy last or mask.
It may cause a NULL pointer (spec) dereference.

This commit adds extra check of item->spec and if it is NULL, does not
copy further data relying on it

Fixes: 841a0445442d ("ethdev: fix GENEVE option item conversion")
Cc: michaelba at nvidia.com
Cc: adrien.mazarguil at 6wind.com
Cc: stephen at networkplumber.org
Cc: stable at dpdk.org

Signed-off-by: Denis Lyulin <lyulin.2003 at mail.ru>
---
 lib/ethdev/rte_flow.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
index fe8f43caff..7a51b667cf 100644
--- a/lib/ethdev/rte_flow.c
+++ b/lib/ethdev/rte_flow.c
@@ -672,13 +672,17 @@ rte_flow_conv_item_spec(void *buf, const size_t size,
 			   }),
 			   size > sizeof(*dst.raw) ? sizeof(*dst.raw) : size);
 		off = sizeof(*dst.raw);
-		if (type == RTE_FLOW_CONV_ITEM_SPEC ||
-		    (type == RTE_FLOW_CONV_ITEM_MASK &&
-		     ((spec.raw->length & mask.raw->length) >=
-		      (last.raw->length & mask.raw->length))))
+		if (type == RTE_FLOW_CONV_ITEM_SPEC && spec.raw)
 			tmp = spec.raw->length & mask.raw->length;
-		else
+		else if (type == RTE_FLOW_CONV_ITEM_MASK && spec.raw && last.raw &&
+			 ((spec.raw->length & mask.raw->length) >=
+			  (last.raw->length & mask.raw->length)))
+			tmp = spec.raw->length & mask.raw->length;
+		else if (last.raw)
 			tmp = last.raw->length & mask.raw->length;
+		else
+			tmp = 0;
+
 		if (tmp) {
 			off = RTE_ALIGN_CEIL(off, sizeof(*dst.raw->pattern));
 			if (size >= off + tmp) {
@@ -696,8 +700,8 @@ rte_flow_conv_item_spec(void *buf, const size_t size,
 		spec.geneve_opt = item->spec;
 		src.geneve_opt = data;
 		dst.geneve_opt = buf;
-		tmp = spec.geneve_opt->option_len << 2;
-		if (size > 0 && src.geneve_opt->data) {
+		tmp = spec.geneve_opt ? (spec.geneve_opt->option_len << 2) : 0;
+		if (size > 0 && tmp > 0 && src.geneve_opt->data) {
 			deep_src = (void *)((uintptr_t)(dst.geneve_opt + 1));
 			dst.geneve_opt->data = rte_memcpy(deep_src,
 							  src.geneve_opt->data,
-- 
2.34.1