diff mbox series

[v4] net/i40e: fix the core dump risk of wild pointer operation

Message ID 20200518074330.35840-1-wei.zhao1@intel.com (mailing list archive)
State Superseded, archived
Delegated to: xiaolong ye
Headers
Series [v4] net/i40e: fix the core dump risk of wild pointer operation |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK
ci/travis-robot success Travis build: passed

Commit Message

Zhao1, Wei May 18, 2020, 7:43 a.m. UTC 
  In i40e PMD code of function i40e_res_pool_free(), if valid_entry
is freed by "rte_free(valid_entry);" in the code, then the following
code for pool update may still use the wild pointer "valid_entry"
for pool info update. It seems has the risk of core dump for
using wild pointer operation, we should avoid this risk.

Cc: stable@dpdk.org
Fixes: 4861cde46116 ("i40e: new poll mode driver")

Signed-off-by: Wei Zhao <wei.zhao1@intel.com>

---

v2:
update commit log

v3:
set free pointer to NULL

v4:
change code style
---
 drivers/net/i40e/i40e_ethdev.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index 749d85f54..679d59e5d 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -4935,6 +4935,7 @@  i40e_res_pool_free(struct i40e_res_pool_info *pool,
 {
 	struct pool_entry *entry, *next, *prev, *valid_entry = NULL;
 	uint32_t pool_offset;
+	uint16_t len;
 	int insert;
 
 	if (pool == NULL) {
@@ -4973,12 +4974,13 @@  i40e_res_pool_free(struct i40e_res_pool_info *pool,
 	}
 
 	insert = 0;
+	len = valid_entry->len;
 	/* Try to merge with next one*/
 	if (next != NULL) {
 		/* Merge with next one */
-		if (valid_entry->base + valid_entry->len == next->base) {
+		if (valid_entry->base + len == next->base) {
 			next->base = valid_entry->base;
-			next->len += valid_entry->len;
+			next->len += len;
 			rte_free(valid_entry);
 			valid_entry = next;
 			insert = 1;
@@ -4987,14 +4989,16 @@  i40e_res_pool_free(struct i40e_res_pool_info *pool,
 
 	if (prev != NULL) {
 		/* Merge with previous one */
-		if (prev->base + prev->len == valid_entry->base) {
-			prev->len += valid_entry->len;
+		if (prev->base + len == valid_entry->base) {
+			prev->len += len;
 			/* If it merge with next one, remove next node */
 			if (insert == 1) {
 				LIST_REMOVE(valid_entry, next);
 				rte_free(valid_entry);
+				valid_entry = NULL;
 			} else {
 				rte_free(valid_entry);
+				valid_entry = NULL;
 				insert = 1;
 			}
 		}
@@ -5010,8 +5014,8 @@  i40e_res_pool_free(struct i40e_res_pool_info *pool,
 			LIST_INSERT_HEAD(&pool->free_list, valid_entry, next);
 	}
 
-	pool->num_free += valid_entry->len;
-	pool->num_alloc -= valid_entry->len;
+	pool->num_free += len;
+	pool->num_alloc -= len;
 
 	return 0;
 }