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| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-06-20 22:35:05 -0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-06-28 17:20:43 -0400 |
| commit | 64bd577ea0021f5903505de061b3b7d8a785ee94 (patch) | |
| tree | 7081480d903325bb82d2384b69cff4579f289de1 /fs/nfs/nfs2xdr.c | |
| parent | c337d3655ce85e12c7c476cb81406521926cacd2 (diff) | |
| download | linux-64bd577ea0021f5903505de061b3b7d8a785ee94.tar.bz2 | |
NFS: Let xdr_read_pages() check for buffer overflows
xdr_read_pages will already do all of the buffer overflow checks that are
currently being open-coded in the various callers. This patch simplifies
the existing code by replacing the open coded checks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/nfs2xdr.c')
| -rw-r--r-- | fs/nfs/nfs2xdr.c | 22 |
1 files changed, 3 insertions, 19 deletions
diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c index db81166182c9..d04f0df7be55 100644 --- a/fs/nfs/nfs2xdr.c +++ b/fs/nfs/nfs2xdr.c @@ -106,19 +106,16 @@ static void print_overflow_msg(const char *func, const struct xdr_stream *xdr) static int decode_nfsdata(struct xdr_stream *xdr, struct nfs_readres *result) { u32 recvd, count; - size_t hdrlen; __be32 *p; p = xdr_inline_decode(xdr, 4); if (unlikely(p == NULL)) goto out_overflow; count = be32_to_cpup(p); - hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base; - recvd = xdr->buf->len - hdrlen; + recvd = xdr_read_pages(xdr, count); if (unlikely(count > recvd)) goto out_cheating; out: - xdr_read_pages(xdr, count); result->eof = 0; /* NFSv2 does not pass EOF flag on the wire. */ result->count = count; return count; @@ -440,7 +437,6 @@ static void encode_path(struct xdr_stream *xdr, struct page **pages, u32 length) static int decode_path(struct xdr_stream *xdr) { u32 length, recvd; - size_t hdrlen; __be32 *p; p = xdr_inline_decode(xdr, 4); @@ -449,12 +445,9 @@ static int decode_path(struct xdr_stream *xdr) length = be32_to_cpup(p); if (unlikely(length >= xdr->buf->page_len || length > NFS_MAXPATHLEN)) goto out_size; - hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base; - recvd = xdr->buf->len - hdrlen; + recvd = xdr_read_pages(xdr, length); if (unlikely(length > recvd)) goto out_cheating; - - xdr_read_pages(xdr, length); xdr_terminate_string(xdr->buf, length); return 0; out_size: @@ -972,16 +965,7 @@ out_overflow: */ static int decode_readdirok(struct xdr_stream *xdr) { - u32 recvd, pglen; - size_t hdrlen; - - pglen = xdr->buf->page_len; - hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base; - recvd = xdr->buf->len - hdrlen; - if (pglen > recvd) - pglen = recvd; - xdr_read_pages(xdr, pglen); - return pglen; + return xdr_read_pages(xdr, xdr->buf->page_len); } static int nfs2_xdr_dec_readdirres(struct rpc_rqst *req, |