This is a note to let you know that I've just added the patch titled
ceph: fix memory leak in ceph_readdir when note_last_dentry returns error
to the 5.16-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:
ceph-fix-memory-leak-in-ceph_readdir-when-note_last_.patch
and it can be found in the queue-5.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1133bac425a3877b5860d4edfcd0109587396a54
Author: Xiubo Li <xiubli@xxxxxxxxxx>
Date: Sat Mar 5 19:52:59 2022 +0800
ceph: fix memory leak in ceph_readdir when note_last_dentry returns error
[ Upstream commit f639d9867eea647005dc824e0e24f39ffc50d4e4 ]
Reset the last_readdir at the same time, and add a comment explaining
why we don't free last_readdir when dir_emit returns false.
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 133dbd9338e7..d91fa53e12b3 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -478,8 +478,11 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
2 : (fpos_off(rde->offset) + 1);
err = note_last_dentry(dfi, rde->name, rde->name_len,
next_offset);
- if (err)
+ if (err) {
+ ceph_mdsc_put_request(dfi->last_readdir);
+ dfi->last_readdir = NULL;
return err;
+ }
} else if (req->r_reply_info.dir_end) {
dfi->next_offset = 2;
/* keep last name */
@@ -520,6 +523,12 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
if (!dir_emit(ctx, rde->name, rde->name_len,
ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
le32_to_cpu(rde->inode.in->mode) >> 12)) {
+ /*
+ * NOTE: Here no need to put the 'dfi->last_readdir',
+ * because when dir_emit stops us it's most likely
+ * doesn't have enough memory, etc. So for next readdir
+ * it will continue.
+ */
dout("filldir stopping us...\n");
return 0;
}
