From c77efc1e7884c818ba67ec36b08e220202d9428c Mon Sep 17 00:00:00 2001 From: Kinglong Mee Date: Thu, 14 Jul 2016 12:02:01 +0800 Subject: [PATCH] nfs/blocklayout: Check max uuids and devices before decoding Avoid nfs return uuids/devices larger than maximum. Signed-off-by: Kinglong Mee Signed-off-by: Trond Myklebust --- fs/nfs/blocklayout/dev.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c index 7d9f570e1b52..118252fd1d64 100644 --- a/fs/nfs/blocklayout/dev.c +++ b/fs/nfs/blocklayout/dev.c @@ -65,8 +65,8 @@ nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b) if (!p) return -EIO; b->simple.nr_sigs = be32_to_cpup(p++); - if (!b->simple.nr_sigs) { - dprintk("no signature\n"); + if (!b->simple.nr_sigs || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) { + dprintk("Bad signature count: %d\n", b->simple.nr_sigs); return -EIO; } @@ -105,7 +105,12 @@ nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b) p = xdr_inline_decode(xdr, 4); if (!p) return -EIO; + b->concat.volumes_count = be32_to_cpup(p++); + if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) { + dprintk("Too many volumes: %d\n", b->concat.volumes_count); + return -EIO; + } p = xdr_inline_decode(xdr, b->concat.volumes_count * 4); if (!p) @@ -117,8 +122,13 @@ nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b) p = xdr_inline_decode(xdr, 8 + 4); if (!p) return -EIO; + p = xdr_decode_hyper(p, &b->stripe.chunk_size); b->stripe.volumes_count = be32_to_cpup(p++); + if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) { + dprintk("Too many volumes: %d\n", b->stripe.volumes_count); + return -EIO; + } p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4); if (!p) -- 2.30.2