From: David Disseldorp <ddiss@xxxxxxx> [ Upstream commit 9cef2a7955f2754257a7cddedec16edae7b587d0 ] RFC 2307 states: For CHAP [RFC1994], in the first step, the initiator MUST send: CHAP_A=<A1,A2...> Where A1,A2... are proposed algorithms, in order of preference. ... For the Algorithm, as stated in [RFC1994], one value is required to be implemented: 5 (CHAP with MD5) LIO currently checks for this value by only comparing a single byte in the tokenized Algorithm string, which means that any value starting with a '5' (e.g. "55") is interpreted as "CHAP with MD5". Fix this by comparing the entire tokenized string. Reviewed-by: Lee Duncan <lduncan@xxxxxxxx> Reviewed-by: Mike Christie <mchristi@xxxxxxxxxx> Signed-off-by: David Disseldorp <ddiss@xxxxxxx> Link: https://lore.kernel.org/r/20190912095547.22427-2-ddiss@xxxxxxx Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/target/iscsi/iscsi_target_auth.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c index 51ddca2033e0..8fe9b12a07a4 100644 --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -70,7 +70,7 @@ static int chap_check_algorithm(const char *a_str) if (!token) goto out; - if (!strncmp(token, "5", 1)) { + if (!strcmp(token, "5")) { pr_debug("Selected MD5 Algorithm\n"); kfree(orig); return CHAP_DIGEST_MD5; -- 2.20.1