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authorBjörn Töpel <bjorn.topel@intel.com>2019-09-04 13:49:11 +0200
committerDaniel Borkmann <daniel@iogearbox.net>2019-09-05 14:11:52 +0200
commit9764f4b301c3e7eb3b75eec85b73cad449cdbb0d (patch)
tree31b08153807248a101bd3d1c5018c3d9b5fd45ab /net/xdp/xsk.c
parentxsk: avoid store-tearing when assigning queues (diff)
downloadlinux-dev-9764f4b301c3e7eb3b75eec85b73cad449cdbb0d.tar.xz
linux-dev-9764f4b301c3e7eb3b75eec85b73cad449cdbb0d.zip
xsk: avoid store-tearing when assigning umem
The umem member of struct xdp_sock is read outside of the control mutex, in the mmap implementation, and needs a WRITE_ONCE to avoid potential store-tearing. Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Fixes: 423f38329d26 ("xsk: add umem fill queue support and mmap") Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'net/xdp/xsk.c')
-rw-r--r--net/xdp/xsk.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 271d8d3fb11e..8c9056f06989 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -644,7 +644,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
}
xdp_get_umem(umem_xs->umem);
- xs->umem = umem_xs->umem;
+ WRITE_ONCE(xs->umem, umem_xs->umem);
sockfd_put(sock);
} else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) {
err = -EINVAL;
@@ -751,7 +751,7 @@ static int xsk_setsockopt(struct socket *sock, int level, int optname,
/* Make sure umem is ready before it can be seen by others */
smp_wmb();
- xs->umem = umem;
+ WRITE_ONCE(xs->umem, umem);
mutex_unlock(&xs->mutex);
return 0;
}