[PATCH 4.19 32/93] net/tls: swap sk_write_space on close

From: Greg Kroah-Hartman
Date: Wed Sep 04 2019 - 14:06:17 EST


From: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>

[ Upstream commit 57c722e932cfb82e9820bbaae1b1f7222ea97b52 ]

Now that we swap the original proto and clear the ULP pointer
on close we have to make sure no callback will try to access
the freed state. sk_write_space is not part of sk_prot, remember
to swap it.

Reported-by: syzbot+dcdc9deefaec44785f32@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 95fa145479fb ("bpf: sockmap/tls, close can race with map free")
Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tls/tls_main.c | 1 +
1 file changed, 1 insertion(+)

--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -301,6 +301,7 @@ static void tls_sk_proto_close(struct so
#else
{
#endif
+ sk->sk_write_space = ctx->sk_write_space;
tls_ctx_free(ctx);
ctx = NULL;
}