diff options
author | J. Bruce Fields <bfields@redhat.com> | 2012-12-04 18:25:10 -0500 |
---|---|---|
committer | Xavier Boudet <x-boudet@ti.com> | 2013-01-14 09:38:08 +0100 |
commit | 32dbb3cfea2c40727acbf01d40b53ef1dcd1d6de (patch) | |
tree | 7c906d6b72e21abad8f931fe1d24795a87eeb022 /fs | |
parent | 4d7c6bbe425e4a4ecad6dda6f1745641f40fb788 (diff) |
nfsd4: fix oops on unusual readlike compound
commit d5f50b0c290431c65377c4afa1c764e2c3fe5305 upstream.
If the argument and reply together exceed the maximum payload size, then
a reply with a read-like operation can overlow the rq_pages array.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/nfsd/nfs4xdr.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 283d15e9f46d..967d68eef282 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2920,11 +2920,16 @@ nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr, len = maxcount; v = 0; while (len > 0) { - pn = resp->rqstp->rq_resused++; + pn = resp->rqstp->rq_resused; + if (!resp->rqstp->rq_respages[pn]) { /* ran out of pages */ + maxcount -= len; + break; + } resp->rqstp->rq_vec[v].iov_base = page_address(resp->rqstp->rq_respages[pn]); resp->rqstp->rq_vec[v].iov_len = len < PAGE_SIZE ? len : PAGE_SIZE; + resp->rqstp->rq_resused++; v++; len -= PAGE_SIZE; } @@ -2970,6 +2975,8 @@ nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd return nfserr; if (resp->xbuf->page_len) return nfserr_resource; + if (!resp->rqstp->rq_respages[resp->rqstp->rq_resused]) + return nfserr_resource; page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]); @@ -3019,6 +3026,8 @@ nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4 return nfserr; if (resp->xbuf->page_len) return nfserr_resource; + if (!resp->rqstp->rq_respages[resp->rqstp->rq_resused]) + return nfserr_resource; RESERVE_SPACE(NFS4_VERIFIER_SIZE); savep = p; |