From 2f73f37d66774587a0d5053e365736e10fc98c41 Mon Sep 17 00:00:00 2001 From: Jorge Mora Date: Thu, 25 Jan 2024 07:45:28 -0700 Subject: NFSD: fix LISTXATTRS returning a short list with eof=TRUE If the XDR buffer is not large enough to fit all attributes and the remaining bytes left in the XDR buffer (xdrleft) is equal to the number of bytes for the current attribute, then the loop will prematurely exit without setting eof to FALSE. Also in this case, adding the eof flag to the buffer will make the reply 4 bytes larger than lsxa_maxcount. Need to check if there are enough bytes to fit not only the next attribute name but also the eof as well. Fixes: 23e50fe3a5e6 ("nfsd: implement the xattr functions and en/decode logic") Signed-off-by: Jorge Mora Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever --- fs/nfsd/nfs4xdr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/nfsd') diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 5649076df4b4..840ecd7eaf07 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -5447,7 +5447,8 @@ nfsd4_encode_listxattrs(struct nfsd4_compoundres *resp, __be32 nfserr, slen -= XATTR_USER_PREFIX_LEN; xdrlen = 4 + ((slen + 3) & ~3); - if (xdrlen > xdrleft) { + /* Check if both entry and eof can fit in the XDR buffer */ + if (xdrlen + XDR_UNIT > xdrleft) { if (count == 0) { /* * Can't even fit the first attribute name. -- cgit v1.2.3