From 97826c821ec6724fc359d9b7840dc10af914c641 Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Wed, 13 Nov 2013 16:51:06 +0000
Subject: [PATCH] KEYS: Fix error handling in big_key instantiation
In the big_key_instantiate() function we return 0 if kernel_write() returns us
an error rather than returning an error. This can potentially lead to
dentry_open() giving a BUG when called from big_key_read() with an unset
tmpfile path.
------------[ cut here ]------------
kernel BUG at fs/open.c:798!
...
RIP: 0010:[<ffffffff8119bbd1>] dentry_open+0xd1/0xe0
...
Call Trace:
[<ffffffff812350c5>] big_key_read+0x55/0x100
[<ffffffff81231084>] keyctl_read_key+0xb4/0xe0
[<ffffffff81231e58>] SyS_keyctl+0xf8/0x1d0
[<ffffffff815bb799>] system_call_fastpath+0x16/0x1b
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>
---
security/keys/big_key.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/security/keys/big_key.c b/security/keys/big_key.c
index 2cf5e62d67af..7f44c3207a9b 100644
--- a/security/keys/big_key.c
+++ b/security/keys/big_key.c
@@ -78,6 +78,7 @@ int big_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
written = kernel_write(file, prep->data, prep->datalen, 0);
if (written != datalen) {
+ ret = written;
if (written >= 0)
ret = -ENOMEM;
goto err_fput;
--
2.34.1