diff mbox series

[v3,1/2] ceph: skip copying the data extends the file EOF

Message ID 20240319002925.1228063-2-xiubli@redhat.com
State New
Headers show
Series [v3,1/2] ceph: skip copying the data extends the file EOF | expand

Commit Message

Xiubo Li March 19, 2024, 12:29 a.m. UTC 
From: Xiubo Li <xiubli@redhat.com>

If hits the EOF it will revise the return value to the i_size
instead of the real length read, but it will advance the offset
of iovc, then for the next try it may be incorrectly skipped.

This will just skip advancing the iovc's offset more than i_size.

URL: https://patchwork.kernel.org/project/ceph-devel/list/?series=819323
Reported-by: Frank Hsiao 蕭法宣 <frankhsiao@qnap.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Tested-by: Frank Hsiao 蕭法宣 <frankhsiao@qnap.com>
---
 fs/ceph/file.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)
diff mbox series

Patch

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 24a003eaa5e0..c35878427985 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1200,7 +1200,12 @@  ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 		}
 
 		idx = 0;
-		left = ret > 0 ? ret : 0;
+		if (ret <= 0)
+			left = 0;
+		else if (off + ret > i_size)
+			left = i_size - off;
+		else
+			left = ret;
 		while (left > 0) {
 			size_t plen, copied;
 
@@ -1229,15 +1234,13 @@  ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 	}
 
 	if (ret > 0) {
-		if (off > *ki_pos) {
-			if (off >= i_size) {
-				*retry_op = CHECK_EOF;
-				ret = i_size - *ki_pos;
-				*ki_pos = i_size;
-			} else {
-				ret = off - *ki_pos;
-				*ki_pos = off;
-			}
+		if (off >= i_size) {
+			*retry_op = CHECK_EOF;
+			ret = i_size - *ki_pos;
+			*ki_pos = i_size;
+		} else {
+			ret = off - *ki_pos;
+			*ki_pos = off;
 		}
 
 		if (last_objver)