block: sed-opal: Fix a couple off by one bugs

BugLink: https://bugs.launchpad.net/bugs/1835845
[ Upstream commit ce042c183bcb94eb2919e8036473a1fc203420f9 ]

resp->num is the number of tokens in resp->tok[].  It gets set in
response_parse().  So if n == resp->num then we're reading beyond the
end of the data.

Fixes: 455a7b238cd6 ("block: Add Sed-opal library")
Reviewed-by: Scott Bauer <scott.bauer@intel.com>
Tested-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/block/sed-opal.c b/block/sed-opal.c
index 9ed51d0c6b1d171fc2eab785ef854b64f93721fe..4f5e70d4abc3cd282db163c6614b24c31a4c0fe5 100644 (file)
--- a/block/sed-opal.c
+++ b/block/sed-opal.c
@@ -877,7 +877,7 @@ static size_t response_get_string(const struct parsed_resp *resp, int n,
                return 0;
        }
 
-       if (n > resp->num) {
+       if (n >= resp->num) {
                pr_debug("Response has %d tokens. Can't access %d\n",
                         resp->num, n);
                return 0;
@@ -899,7 +899,7 @@ static u64 response_get_u64(const struct parsed_resp *resp, int n)
                return 0;
        }
 
-       if (n > resp->num) {
+       if (n >= resp->num) {
                pr_debug("Response has %d tokens. Can't access %d\n",
                         resp->num, n);
                return 0;