Ksawlii/kernel_samsung_a53x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

mptcp: fix lockless access in subflow ULP diag

Browse source 
commit b8adb69a7d29c2d33eb327bca66476fb6066516b upstream.

Since the introduction of the subflow ULP diag interface, the
dump callback accessed all the subflow data with lockless.

We need either to annotate all the read and write operation accordingly,
or acquire the subflow socket lock. Let's do latter, even if slower, to
avoid a diffstat havoc.

Fixes: 5147dfb50832 ("mptcp: allow dumping subflow context to userspace")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Paolo Abeni 2024-02-15 19:25:30 +01:00 • committed by Ksawlii
parent e878a862fb
commit 92f22dbef1
3 changed files with 7 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
include/net/tcp.h
View file

@ -2235,7 +2235,7 @@ struct tcp_ulp_ops {
/* cleanup ulp */
void (*release)(struct sock *sk);
/* diagnostic */
int (*get_info)(const struct sock *sk, struct sk_buff *skb);
int (*get_info)(struct sock *sk, struct sk_buff *skb);
size_t (*get_info_size)(const struct sock *sk);
/* clone ulp */
void (*clone)(const struct request_sock *req, struct sock *newsk,

6
net/mptcp/diag.c
View file

@ -13,17 +13,19 @@
#include <uapi/linux/mptcp.h>
#include "protocol.h"
static int subflow_get_info(const struct sock *sk, struct sk_buff *skb)
static int subflow_get_info(struct sock *sk, struct sk_buff *skb)
{
struct mptcp_subflow_context *sf;
struct nlattr *start;
u32 flags = 0;
bool slow;
int err;
start = nla_nest_start_noflag(skb, INET_ULP_INFO_MPTCP);
if (!start)
return -EMSGSIZE;
slow = lock_sock_fast(sk);
rcu_read_lock();
sf = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
if (!sf) {
@ -69,11 +71,13 @@ static int subflow_get_info(const struct sock *sk, struct sk_buff *skb)
}
rcu_read_unlock();
unlock_sock_fast(sk, slow);
nla_nest_end(skb, start);
return 0;
nla_failure:
rcu_read_unlock();
unlock_sock_fast(sk, slow);
nla_nest_cancel(skb, start);
return err;
}

2
net/tls/tls_main.c
View file

@ -800,7 +800,7 @@ static void tls_update(struct sock *sk, struct proto *p,
}
}
static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
static int tls_get_info(struct sock *sk, struct sk_buff *skb)
{
u16 version, cipher_type;
struct tls_context *ctx;