cifs: Replace wrtPending with a real reference count
Currently, cifs_close() tries to wait until all I/O is complete and then
frees the file private data. If I/O does not completely in a reasonable
amount of time it frees the structure anyway, leaving a potential use-
after-free situation.
This patch changes the wrtPending counter to a complete reference count and
lets the last user free the structure.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 6941c22..7dfe084 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -607,7 +607,7 @@
return get_cifs_acl_by_path(cifs_sb, path, pacllen);
pntsd = get_cifs_acl_by_fid(cifs_sb, open_file->netfid, pacllen);
- atomic_dec(&open_file->wrtPending);
+ cifsFileInfo_put(open_file);
return pntsd;
}
@@ -665,7 +665,7 @@
return set_cifs_acl_by_path(cifs_sb, path, pnntsd, acllen);
rc = set_cifs_acl_by_fid(cifs_sb, open_file->netfid, pnntsd, acllen);
- atomic_dec(&open_file->wrtPending);
+ cifsFileInfo_put(open_file);
return rc;
}