Looks like there are still cases when "space_left - frag1bytes" can legitimately exceed PAGE_SIZE. Ensure that xdr->end always remains within the current encode buffer. Reported-by: Bruce Fields <bfields@xxxxxxxxxxxx> Reported-by: Zorro Lang <zlang@xxxxxxxxxx> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216151 Fixes: 6c254bf3b637 ("SUNRPC: Fix the calculation of xdr->end in xdr_get_next_encode_buffer()") Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- net/sunrpc/xdr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index f87a2d8f23a7..5d2b3e6979fb 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -984,7 +984,7 @@ static noinline __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, p = page_address(*xdr->page_ptr); xdr->p = p + frag2bytes; space_left = xdr->buf->buflen - xdr->buf->len; - if (space_left - nbytes >= PAGE_SIZE) + if (space_left - frag1bytes >= PAGE_SIZE) xdr->end = p + PAGE_SIZE; else xdr->end = p + space_left - frag1bytes;
