[PATCH v2] target: fix a missing check of match_int

From: Kangjie Lu
Date: Sat Jan 12 2019 - 00:32:58 EST


When match_int fails, "arg" is left uninitialized and may contain random
value, thus should not be used.
The fix checks if match_int fails, and if so, returns its error code.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
---
drivers/target/target_core_rd.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
index a6e8106abd6f..3b7657b2f2f1 100644
--- a/drivers/target/target_core_rd.c
+++ b/drivers/target/target_core_rd.c
@@ -559,6 +559,7 @@ static ssize_t rd_set_configfs_dev_params(struct se_device *dev,
char *orig, *ptr, *opts;
substring_t args[MAX_OPT_ARGS];
int arg, token;
+ int ret;

opts = kstrdup(page, GFP_KERNEL);
if (!opts)
@@ -573,14 +574,24 @@ static ssize_t rd_set_configfs_dev_params(struct se_device *dev,
token = match_token(ptr, tokens, args);
switch (token) {
case Opt_rd_pages:
- match_int(args, &arg);
+ ret = match_int(args, &arg);
+ if (ret) {
+ kfree(orig);
+ return ret;
+ }
+
rd_dev->rd_page_count = arg;
pr_debug("RAMDISK: Referencing Page"
" Count: %u\n", rd_dev->rd_page_count);
rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
break;
case Opt_rd_nullio:
- match_int(args, &arg);
+ ret = match_int(args, &arg);
+ if (ret) {
+ kfree(orig);
+ return ret;
+ }
+
if (arg != 1)
break;

--
2.17.2 (Apple Git-113)