4.19-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 8c3c447b3cec27cf6f77080f4d157d53b64e9555 ]
This avoids an indirect call per {send,recv}msg syscall in the common (IPv6 or IPv4 socket) case.
Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: 86a7e0b69bd5 ("net: prevent rewrite of msg_name in sock_sendmsg()") Signed-off-by: Sasha Levin sashal@kernel.org --- net/socket.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/net/socket.c b/net/socket.c index db9d908198f21..dc4d4ecd6cea2 100644 --- a/net/socket.c +++ b/net/socket.c @@ -90,6 +90,7 @@ #include <linux/slab.h> #include <linux/xattr.h> #include <linux/nospec.h> +#include <linux/indirect_call_wrapper.h>
#include <linux/uaccess.h> #include <asm/unistd.h> @@ -108,6 +109,13 @@ #include <net/busy_poll.h> #include <linux/errqueue.h>
+/* proto_ops for ipv4 and ipv6 use the same {recv,send}msg function */ +#if IS_ENABLED(CONFIG_INET) +#define INDIRECT_CALL_INET4(f, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__) +#else +#define INDIRECT_CALL_INET4(f, f1, ...) f(__VA_ARGS__) +#endif + #ifdef CONFIG_NET_RX_BUSY_POLL unsigned int sysctl_net_busy_read __read_mostly; unsigned int sysctl_net_busy_poll __read_mostly; @@ -645,10 +653,12 @@ EXPORT_SYMBOL(__sock_tx_timestamp); * Sends @msg through @sock, passing through LSM. * Returns the number of bytes sent, or an error code. */ - +INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *, + size_t)); static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg) { - int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg)); + int ret = INDIRECT_CALL_INET4(sock->ops->sendmsg, inet_sendmsg, sock, + msg, msg_data_left(msg)); BUG_ON(ret == -EIOCBQUEUED); return ret; } @@ -852,11 +862,13 @@ EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops); * Receives @msg from @sock, passing through LSM. Returns the total number * of bytes received, or an error. */ - +INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *, + size_t , int )); static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg, int flags) { - return sock->ops->recvmsg(sock, msg, msg_data_left(msg), flags); + return INDIRECT_CALL_INET4(sock->ops->recvmsg, inet_recvmsg, sock, msg, + msg_data_left(msg), flags); }
int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)