From eed1e1afd8d542d9644534c1b712599b5d680007 Mon Sep 17 00:00:00 2001 From: Stephan Mueller Date: Mon, 16 May 2016 02:53:36 +0200 Subject: [PATCH] crypto: user - no parsing of CRYPTO_MSG_GETALG The CRYPTO_MSG_GETALG netlink message type provides a buffer to the kernel to retrieve information from the kernel. The data buffer will not provide any input and will not be read. Hence the nlmsg_parse is not applicable to this netlink message type. This patch fixes the following kernel log message when using this netlink interface: netlink: 208 bytes leftover after parsing attributes in process `XXX'. Patch successfully tested with libkcapi from [1] which uses CRYPTO_MSG_GETALG to obtain cipher-specific information from the kernel. [1] http://www.chronox.de/libkcapi.html Signed-off-by: Stephan Mueller Signed-off-by: Herbert Xu --- crypto/crypto_user.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c index 43fe85f20d57..f71960dea882 100644 --- a/crypto/crypto_user.c +++ b/crypto/crypto_user.c @@ -516,10 +516,12 @@ static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return err; } - err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX, - crypto_policy); - if (err < 0) - return err; + if (type != (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE)) { + err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, + CRYPTOCFGA_MAX, crypto_policy); + if (err < 0) + return err; + } if (link->doit == NULL) return -EINVAL; -- 2.20.1