This is a note to let you know that I've just added the patch titled
NFSv4.2: Fix READ_PLUS size calculations
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsv4.2-fix-read_plus-size-calculations.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6928a6168f25e09f01ec7ba8950c91bc38b9576c
Author: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Date: Wed May 31 17:02:54 2023 -0400
NFSv4.2: Fix READ_PLUS size calculations
[ Upstream commit 8d18f6c5bb864d97a730f471c56cdecf313efe64 ]
I bump the decode_read_plus_maxsz to account for hole segments, but I
need to subtract out this increase when calling
rpc_prepare_reply_pages() so the common case of single data segment
replies can be directly placed into the xdr pages without needing to be
shifted around.
Reported-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Fixes: d3b00a802c845 ("NFS: Replace the READ_PLUS decoding code")
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index ef3b150970ff6..75765382cc0e6 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -51,10 +51,16 @@
(1 /* data_content4 */ + \
2 /* data_info4.di_offset */ + \
1 /* data_info4.di_length */)
+#define NFS42_READ_PLUS_HOLE_SEGMENT_SIZE \
+ (1 /* data_content4 */ + \
+ 2 /* data_info4.di_offset */ + \
+ 2 /* data_info4.di_length */)
+#define READ_PLUS_SEGMENT_SIZE_DIFF (NFS42_READ_PLUS_HOLE_SEGMENT_SIZE - \
+ NFS42_READ_PLUS_DATA_SEGMENT_SIZE)
#define decode_read_plus_maxsz (op_decode_hdr_maxsz + \
1 /* rpr_eof */ + \
1 /* rpr_contents count */ + \
- NFS42_READ_PLUS_DATA_SEGMENT_SIZE)
+ NFS42_READ_PLUS_HOLE_SEGMENT_SIZE)
#define encode_seek_maxsz (op_encode_hdr_maxsz + \
encode_stateid_maxsz + \
2 /* offset */ + \
@@ -781,8 +787,8 @@ static void nfs4_xdr_enc_read_plus(struct rpc_rqst *req,
encode_putfh(xdr, args->fh, &hdr);
encode_read_plus(xdr, args, &hdr);
- rpc_prepare_reply_pages(req, args->pages, args->pgbase,
- args->count, hdr.replen);
+ rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->count,
+ hdr.replen - READ_PLUS_SEGMENT_SIZE_DIFF);
encode_nops(&hdr);
}
