On 14/12/2022 02:05, Ilya Dryomov wrote:
On Tue, Dec 13, 2022 at 1:11 PM <xiubli@xxxxxxxxxx> wrote:
From: Xiubo Li <xiubli@xxxxxxxxxx>
When ceph releasing the file_lock it will try to get the inode pointer
from the fl->fl_file, which the memory could already be released by
another thread in filp_close(). Because in VFS layer the fl->fl_file
doesn't increase the file's reference counter.
Will switch to use ceph dedicate lock info to track the inode.
And in ceph_fl_release_lock() we should skip all the operations if
the fl->fl_u.ceph_fl.fl_inode is not set, which should come from
the request file_lock. And we will set fl->fl_u.ceph_fl.fl_inode when
inserting it to the inode lock list, which is when copying the lock.
Cc: stable@xxxxxxxxxxxxxxx
Cc: Jeff Layton <jlayton@xxxxxxxxxx>
URL: https://tracker.ceph.com/issues/57986
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
---
fs/ceph/locks.c | 20 ++++++++++++++++++--
include/linux/fs.h | 3 +++
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c
index b191426bf880..cf78608a3f9a 100644
--- a/fs/ceph/locks.c
+++ b/fs/ceph/locks.c
@@ -34,18 +34,34 @@ static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
{
struct inode *inode = file_inode(dst->fl_file);
atomic_inc(&ceph_inode(inode)->i_filelock_ref);
+ dst->fl_u.ceph.fl_inode = igrab(inode);
}
+/*
+ * Do not use the 'fl->fl_file' in release function, which
+ * is possibly already released by another thread.
+ */
static void ceph_fl_release_lock(struct file_lock *fl)
{
- struct inode *inode = file_inode(fl->fl_file);
- struct ceph_inode_info *ci = ceph_inode(inode);
+ struct inode *inode = fl->fl_u.ceph.fl_inode;
+ struct ceph_inode_info *ci;
+
+ /*
+ * If inode is NULL it should be a request file_lock,
+ * nothing we can do.
+ */
+ if (!inode)
+ return;
+
+ ci = ceph_inode(inode);
if (atomic_dec_and_test(&ci->i_filelock_ref)) {
/* clear error when all locks are released */
spin_lock(&ci->i_ceph_lock);
ci->i_ceph_flags &= ~CEPH_I_ERROR_FILELOCK;
spin_unlock(&ci->i_ceph_lock);
}
+ fl->fl_u.ceph.fl_inode = NULL;
+ iput(inode);
}
static const struct file_lock_operations ceph_fl_lock_ops = {
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7b52fdfb6da0..6106374f5257 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1119,6 +1119,9 @@ struct file_lock {
int state; /* state of grant or error if -ve */
unsigned int debug_id;
} afs;
+ struct {
+ struct inode *fl_inode;
Hi Xiubo,
Nit: I think it could be just "inode", without the prefix which is
already present in the union field name.
Okay, I can fix this in the next version.
Thanks.
- Xiubo
Thanks,
Ilya
