From: "J. Bruce Fields" <bfields@xxxxxxxxxx> Commit 3b299709091b "nfsd4: enforce rd_dircount" totally misunderstood rd_dircount; it refers to total non-attribute bytes returned, not number of directory entries returned. Bring the code into agreement with RFC 3530 section 14.2.24. Cc: stable@xxxxxxxxxx Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx> --- fs/nfsd/nfs4xdr.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index f9821ce6658a..e94457c33ad6 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2657,6 +2657,7 @@ nfsd4_encode_dirent(void *ccdv, const char *name, int namlen, struct xdr_stream *xdr = cd->xdr; int start_offset = xdr->buf->len; int cookie_offset; + u32 name_and_cookie; int entry_bytes; __be32 nfserr = nfserr_toosmall; __be64 wire_offset; @@ -2718,7 +2719,14 @@ nfsd4_encode_dirent(void *ccdv, const char *name, int namlen, cd->rd_maxcount -= entry_bytes; if (!cd->rd_dircount) goto fail; - cd->rd_dircount--; + /* + * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so + * let's always let through the first entry, at least: + */ + name_and_cookie = 4 * XDR_QUADLEN(namlen) + 8; + if (name_and_cookie > cd->rd_dircount && cd->cookie_offset) + goto fail; + cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie); cd->cookie_offset = cookie_offset; skip_entry: cd->common.err = nfs_ok; @@ -3321,6 +3329,10 @@ nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4 } maxcount = min_t(int, maxcount-16, bytes_left); + /* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */ + if (!readdir->rd_dircount) + readdir->rd_dircount = INT_MAX; + readdir->xdr = xdr; readdir->rd_maxcount = maxcount; readdir->common.err = 0; -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
