[PATCH 02/10] nfsd: fix potential lease memory leak in nfs4_setlease

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



It's unlikely to ever occur, but if there were already a lease set on
the file then we could end up getting back a different pointer on a
successful setlease attempt than the one we allocated. If that happens,
the one we allocated could leak.

In practice, I don't think this will happen due to the fact that we only
try to set up the lease once per nfs4_file, but this error handling is a
bit more correct given the current lease API.

Cc: J. Bruce Fields <bfields@xxxxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
---
 fs/nfsd/nfs4state.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index fd5ff4b17292..29fac18d9102 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3774,7 +3774,7 @@ static struct file_lock *nfs4_alloc_init_lease(struct nfs4_file *fp, int flag)
 static int nfs4_setlease(struct nfs4_delegation *dp)
 {
 	struct nfs4_file *fp = dp->dl_stid.sc_file;
-	struct file_lock *fl;
+	struct file_lock *fl, *ret;
 	struct file *filp;
 	int status = 0;
 
@@ -3788,11 +3788,14 @@ static int nfs4_setlease(struct nfs4_delegation *dp)
 		return -EBADF;
 	}
 	fl->fl_file = filp;
-	status = vfs_setlease(filp, fl->fl_type, &fl);
+	ret = fl;
+	status = vfs_setlease(filp, fl->fl_type, &ret);
 	if (status) {
 		locks_free_lock(fl);
 		goto out_fput;
 	}
+	if (ret != fl)
+		locks_free_lock(fl);
 	spin_lock(&state_lock);
 	spin_lock(&fp->fi_lock);
 	/* Did the lease get broken before we took the lock? */
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]
  Powered by Linux