kmemdup can return a null pointer so need to check for it, otherwise the null key will be dereferenced later in tipc_crypto_key_xmit as can be seen in the trace [1]. Cc: tipc-discussion@lists.sourceforge.net Cc: stable@vger.kernel.org # 5.15, 5.14, 5.10 [1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58 Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org> Acked-by: Ying Xue <ying.xue@windriver.com> Acked-by: Jon Maloy <jmaloy@redhat.com> Link: https://lore.kernel.org/r/20211115160143.5099-1-tadeusz.struk@linaro.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>