[PATCH v13 09/20] net, arm64: untag user pointers in tcp_zerocopy_receive
From: Andrey Konovalov <hidden>
Date: 2019-03-20 14:54:35
Also in:
bpf, linux-arch, linux-kselftest, linux-media, linux-mm, lkml
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. tcp_zerocopy_receive() uses provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in this function. Signed-off-by: Andrey Konovalov <redacted> --- net/ipv4/tcp.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 6baa6dc1b13b..855a1f68c1ea 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c@@ -1761,6 +1761,8 @@ static int tcp_zerocopy_receive(struct sock *sk, if (address & (PAGE_SIZE - 1) || address != zc->address) return -EINVAL; + address = untagged_addr(address); + if (sk->sk_state == TCP_LISTEN) return -ENOTCONN;
--
2.21.0.225.g810b269d1ac-goog