diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2012-12-04 18:25:10 -0500 |
|---|---|---|
| committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2014-02-10 16:11:01 -0500 |
| commit | dd17b5298be2e182556ef25ce9108343089e77e5 (patch) | |
| tree | 6a3fa2330f4bbb6f6793ec6d69b64a87692b3a35 /fs | |
| parent | cbdfb1a8b4d54cfe3ee17d0dba60f41ac87ce068 (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: Paul Gortmaker <paul.gortmaker@windriver.com>
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 28d586a5e77e..3800e7680037 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2607,11 +2607,16 @@ 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; } @@ -2659,6 +2664,8 @@ 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++]); @@ -2708,6 +2715,8 @@ 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(8); /* verifier */ savep = p; |