diff options
author | Björn Töpel <bjorn.topel@intel.com> | 2019-09-04 13:49:11 +0200 |
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committer | Daniel Borkmann <daniel@iogearbox.net> | 2019-09-05 14:11:52 +0200 |
commit | 9764f4b301c3e7eb3b75eec85b73cad449cdbb0d (patch) | |
tree | 31b08153807248a101bd3d1c5018c3d9b5fd45ab /net/xdp | |
parent | 94a997637c5b562fa0ca44fca1d2cd02ec08236f (diff) | |
download | linux-9764f4b301c3e7eb3b75eec85b73cad449cdbb0d.tar.gz |
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')
-rw-r--r-- | net/xdp/xsk.c | 4 |
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; } |