NFSD: Fix bad checking of space for padding in splice read

Fix commit dc97618ddd (nfsd4: separate splice and readv cases). xdr->end and xdr->p are type of __be32 *, so padding needs one here.

Signed-off-by Kinglong Mee <[email protected]>

---
 fs/nfsd/nfs4xdr.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

fs/nfsd/nfs4xdr.c +2 -5

index 523c666..8a2fbb2 100644
@@ -3067,11 +3067,8 @@ static __be32 nfsd4_encode_splice_read(
 	__be32 nfserr;
 	__be32 *p = xdr->p - 2;
 
-	/*
-	 * Don't inline pages unless we know there's room for eof,
-	 * count, and possible padding:
-	 */
-	if (xdr->end - xdr->p < 3)
+	/* Make sure there will be room for padding if needed */
+	if (xdr->end - xdr->p < 1)
 		return nfserr_resource;
 
 	nfserr = nfsd_splice_read(read->rd_rqstp, file,

Signature · 1 line

1.9.3

Quoted 2 lines · Kinglong Mee

Fix commit dc97618ddd (nfsd4: separate splice and readv cases). xdr->end and xdr->p are type of __be32 *, so padding needs one here.

I agree with the patch, but not the changelog.

The problem here is that xdr->p isn't that those are __be32 *'s, but that xdr->p has already advanced past the eof and the count, right?

Applying with an updated changelog.

--b.

Quoted 27 lines

Signed-off-by Kinglong Mee <[email protected]>

---
 fs/nfsd/nfs4xdr.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

fs/nfsd/nfs4xdr.c +2 -5

index 523c666..8a2fbb2 100644
@@ -3067,11 +3067,8 @@ static __be32 nfsd4_encode_splice_read(
 	__be32 nfserr;
 	__be32 *p = xdr->p - 2;
 
-	/*
-	 * Don't inline pages unless we know there's room for eof,
-	 * count, and possible padding:
-	 */
-	if (xdr->end - xdr->p < 3)
+	/* Make sure there will be room for padding if needed */
+	if (xdr->end - xdr->p < 1)
 		return nfserr_resource;
 
 	nfserr = nfsd_splice_read(read->rd_rqstp, file,

Signature · 1 line

1.9.3