Re: [PATCH v2] nfsd: Avoid strlen conflict in nfsd4_encode_components_esc()

[Nathan Chancellor <nathan@kernel.org>]

On Mon, Sep 29, 2025 at 09:05:15AM -0400, Chuck Lever wrote:
> On 9/28/25 4:29 PM, NeilBrown wrote:
> > On Mon, 29 Sep 2025, Nathan Chancellor wrote:
...
> >> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> >> index ea91bad4eee2..9fe8a413f688 100644
> >> --- a/fs/nfsd/nfs4xdr.c
> >> +++ b/fs/nfsd/nfs4xdr.c
> >> @@ -2640,11 +2640,9 @@ static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
> >>  	__be32 *p;
> >>  	__be32 pathlen;
> >>  	int pathlen_offset;
> >> -	int strlen, count=0;
> >> +	int str_len, count=0;
> >>  	char *str, *end, *next;
> >>  
> >> -	dprintk("nfsd4_encode_components(%s)\n", components);
> >> -
> >>  	pathlen_offset = xdr->buf->len;
> >>  	p = xdr_reserve_space(xdr, 4);
> >>  	if (!p)
> >> @@ -2670,9 +2668,9 @@ static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
> >>  			for (; *end && (*end != sep); end++)
> >>  				/* find sep or end of string */;
> >>  
> >> -		strlen = end - str;
> >> -		if (strlen) {
> >> -			if (xdr_stream_encode_opaque(xdr, str, strlen) < 0)
> >> +		str_len = end - str;
> >> +		if (str_len) {
> >> +			if (xdr_stream_encode_opaque(xdr, str, str_len) < 0)
> >>  				return nfserr_resource;
> > 
> > I probably should have said something earlier, and this is definitely
> > bike-shedding material, but .... "str_len" is not a whole lot nicer than
> > "strlen" (or "i") ...
> > 
> > 
> >    if (end > str) {
> > 	if (xdr_stream_encode_opaque(xdr, str, end - str) < 0)
> > 
> > ??
> 
> "len" is actually the typical variable name used in such cases. But I
> didn't want to bug Nathan for a resend.

If "len" is truly preferred, I do not mind sending a v3 with such a
change. I had only kept "str" in the name because there is also
"pathlen" in this function.

Cheers,
Nathan