[PATCH 01/15] afs: Fix key leak in afs_release() and afs_evict_inode()

From: David Howells
Date: Wed May 15 2019 - 12:27:37 EST


Fix afs_release() to go through the cleanup part of the function if
FMODE_WRITE is set rather than exiting through vfs_fsync() (which skips the
cleanup). The cleanup involves discarding the refs on the key used for
file ops and the writeback key record.

Also fix afs_evict_inode() to clean up any left over wb keys attached to
the inode/vnode when it is removed.

Fixes: 5a8132761609 ("afs: Do better accretion of small writes on newly created content")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/afs/file.c | 7 ++++---
fs/afs/inode.c | 1 +
2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/afs/file.c b/fs/afs/file.c
index e8d6619890a9..eee2b5663b92 100644
--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -170,11 +170,12 @@ int afs_release(struct inode *inode, struct file *file)
{
struct afs_vnode *vnode = AFS_FS_I(inode);
struct afs_file *af = file->private_data;
+ int ret;

_enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode);

if ((file->f_mode & FMODE_WRITE))
- return vfs_fsync(file, 0);
+ ret = vfs_fsync(file, 0);

file->private_data = NULL;
if (af->wb)
@@ -182,8 +183,8 @@ int afs_release(struct inode *inode, struct file *file)
key_put(af->key);
kfree(af);
afs_prune_wb_keys(vnode);
- _leave(" = 0");
- return 0;
+ _leave(" = %d", ret);
+ return ret;
}

/*
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index c4652b42d545..f30aa5eacd39 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -573,6 +573,7 @@ void afs_evict_inode(struct inode *inode)
}
#endif

+ afs_prune_wb_keys(vnode);
afs_put_permits(rcu_access_pointer(vnode->permit_cache));
key_put(vnode->silly_key);
vnode->silly_key = NULL;