The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From d9539752d23283db4692384a634034f451261e29 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@xxxxxxxxxxxx>
Date: Tue, 9 Jun 2020 16:11:29 -0700
Subject: [PATCH] net/compat: Add missing sock updates for SCM_RIGHTS
Add missed sock updates to compat path via a new helper, which will be
used more in coming patches. (The net/core/scm.c code is left as-is here
to assist with -stable backports for the compat path.)
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Sargun Dhillon <sargun@xxxxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 48a87cc26c13 ("net: netprio: fd passed in SCM_RIGHTS datagram not set correctly")
Fixes: d84295067fc7 ("net: net_cls: fd passed in SCM_RIGHTS datagram not set correctly")
Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
diff --git a/include/net/sock.h b/include/net/sock.h
index c53cc42b5ab9..2be67f1ee8b1 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -890,6 +890,8 @@ static inline int sk_memalloc_socks(void)
{
return static_branch_unlikely(&memalloc_socks_key);
}
+
+void __receive_sock(struct file *file);
#else
static inline int sk_memalloc_socks(void)
@@ -897,6 +899,8 @@ static inline int sk_memalloc_socks(void)
return 0;
}
+static inline void __receive_sock(struct file *file)
+{ }
#endif
static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
diff --git a/net/compat.c b/net/compat.c
index 5e3041a2c37d..2937b816107d 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -309,6 +309,7 @@ void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm)
break;
}
/* Bump the usage count and install the file. */
+ __receive_sock(fp[i]);
fd_install(new_fd, get_file(fp[i]));
}
diff --git a/net/core/sock.c b/net/core/sock.c
index 6c4acf1f0220..bde394979041 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2840,6 +2840,27 @@ int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *
}
EXPORT_SYMBOL(sock_no_mmap);
+/*
+ * When a file is received (via SCM_RIGHTS, etc), we must bump the
+ * various sock-based usage counts.
+ */
+void __receive_sock(struct file *file)
+{
+ struct socket *sock;
+ int error;
+
+ /*
+ * The resulting value of "error" is ignored here since we only
+ * need to take action when the file is a socket and testing
+ * "sock" for NULL is sufficient.
+ */
+ sock = sock_from_file(file, &error);
+ if (sock) {
+ sock_update_netprioidx(&sock->sk->sk_cgrp_data);
+ sock_update_classid(&sock->sk->sk_cgrp_data);
+ }
+}
+
ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
{
ssize_t res;
