diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2017-05-05 20:17:57 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-05-25 13:44:49 (GMT) |
| commit | 51d9c51523ec6927a068ee54280b5a4ff3bf401d (patch) | |
| tree | 830e943dfa89a535594cd821ecc9cbba499ce18d | |
| parent | ea465551af30146efea215da58786ff732da70fb (diff) | |
| download | linux-51d9c51523ec6927a068ee54280b5a4ff3bf401d.tar.xz | |
nfsd: encoders mustn't use unitialized values in error cases
commit f961e3f2acae94b727380c0b74e2d3954d0edf79 upstream.
In error cases, lgp->lg_layout_type may be out of bounds; so we
shouldn't be using it until after the check of nfserr.
This was seen to crash nfsd threads when the server receives a LAYOUTGET
request with a large layout type.
GETDEVICEINFO has the same problem.
Reported-by: Ari Kauppi <Ari.Kauppi@synopsys.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/nfsd/nfs4xdr.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index c2d2895..2ee80e1 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -4081,8 +4081,7 @@ nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getdeviceinfo *gdev) { struct xdr_stream *xdr = &resp->xdr; - const struct nfsd4_layout_ops *ops = - nfsd4_layout_ops[gdev->gd_layout_type]; + const struct nfsd4_layout_ops *ops; u32 starting_len = xdr->buf->len, needed_len; __be32 *p; @@ -4099,6 +4098,7 @@ nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr, /* If maxcount is 0 then just update notifications */ if (gdev->gd_maxcount != 0) { + ops = nfsd4_layout_ops[gdev->gd_layout_type]; nfserr = ops->encode_getdeviceinfo(xdr, gdev); if (nfserr) { /* @@ -4151,8 +4151,7 @@ nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_layoutget *lgp) { struct xdr_stream *xdr = &resp->xdr; - const struct nfsd4_layout_ops *ops = - nfsd4_layout_ops[lgp->lg_layout_type]; + const struct nfsd4_layout_ops *ops; __be32 *p; dprintk("%s: err %d\n", __func__, nfserr); @@ -4175,6 +4174,7 @@ nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr, *p++ = cpu_to_be32(lgp->lg_seg.iomode); *p++ = cpu_to_be32(lgp->lg_layout_type); + ops = nfsd4_layout_ops[lgp->lg_layout_type]; nfserr = ops->encode_layoutget(xdr, lgp); out: kfree(lgp->lg_content); |