2017-05-05 17:07:05

by Trond Myklebust

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Subject: [PATCH] NFSv4: Fix an rcu lock leak

The intention in the original patch was to release the lock when
we put the inode, however something got screwed up.

Reported-by: Jason Yan <[email protected]>
Fixes: 7b410d9ce460f ("pNFS: Delay getting the layout header in..")
Cc: [email protected] # v4.10+
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/callback_proc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index e7f041447afd..52479f180ea1 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -131,10 +131,11 @@ static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
if (!inode)
continue;
if (!nfs_sb_active(inode->i_sb)) {
- rcu_read_lock();
+ rcu_read_unlock();
spin_unlock(&clp->cl_lock);
iput(inode);
spin_lock(&clp->cl_lock);
+ rcu_read_lock();
goto restart;
}
return inode;
@@ -170,10 +171,11 @@ static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
if (!inode)
continue;
if (!nfs_sb_active(inode->i_sb)) {
- rcu_read_lock();
+ rcu_read_unlock();
spin_unlock(&clp->cl_lock);
iput(inode);
spin_lock(&clp->cl_lock);
+ rcu_read_lock();
goto restart;
}
return inode;
--
2.9.3



2017-05-09 19:59:40

by Christoph Hellwig

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Subject: Re: [PATCH] NFSv4: Fix an rcu lock leak

Looks good,

Reviewed-by: Christoph Hellwig <[email protected]>