[PATCH 6.18 199/396] afs: Fix afs_fs_fetch_data() to subtract transferred from len

[Greg Kroah-Hartman]

6.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells at redhat.com>

commit 222052c6be186f2074b3a4d741d5de200f654c43 upstream.

Fix afs_fs_fetch_data() to subtract subreq->transferred from subreq->len
rather than adding it.

Fixes: f28fc2010d62 ("afs: Eliminate afs_read")
Link: https://sashiko.dev/#/patchset/20260713081022.2186481-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells at redhat.com>
Link: https://patch.msgid.link/20260723113452.566619-3-dhowells@redhat.com
cc: Marc Dionne <marc.dionne at auristor.com>
cc: Jeffrey Altman <jaltman at auristor.com>
cc: linux-afs at lists.infradead.org
cc: stable at kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner at kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 fs/afs/fsclient.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 626e1d37b915..1a3f186a6a11 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -487,7 +487,7 @@ void afs_fs_fetch_data(struct afs_operation *op)
 	bp[2] = htonl(vp->fid.vnode);
 	bp[3] = htonl(vp->fid.unique);
 	bp[4] = htonl(lower_32_bits(subreq->start + subreq->transferred));
-	bp[5] = htonl(lower_32_bits(subreq->len   + subreq->transferred));
+	bp[5] = htonl(lower_32_bits(subreq->len   - subreq->transferred));
 
 	call->fid = vp->fid;
 	trace_afs_make_fs_call(call, &vp->fid);
-- 
2.55.0