[PATCH 4.9 17/77] target/iscsi: avoid NULL dereference in CHAP auth error path

4.9-stable review patch. If anyone has any objections, please let me know. -- From: David Disseldorp commit ce512d79d0466a604793addb6b769d12ee326822 upstream. If chap_server_compute_md5() fails early, e.g. via CHAP_N mismatch, then crypto_free_shash() is called

[PATCH 4.9 17/77] target/iscsi: avoid NULL dereference in CHAP auth error path

4.9-stable review patch. If anyone has any objections, please let me know. -- From: David Disseldorp commit ce512d79d0466a604793addb6b769d12ee326822 upstream. If chap_server_compute_md5() fails early, e.g. via CHAP_N mismatch, then crypto_free_shash() is called with a NULL