4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Biggers <ebiggers@xxxxxxxxxx>
commit cc1780fc42c76c705dd07ea123f1143dc5057630 upstream.
Align the payload of "user" and "logon" keys so that users of the
keyrings service can access it as a struct that requires more than
2-byte alignment. fscrypt currently does this which results in the read
of fscrypt_key::size being misaligned as it needs 4-byte alignment.
Align to __alignof__(u64) rather than __alignof__(long) since in the
future it's conceivable that people would use structs beginning with
u64, which on some platforms would require more than 'long' alignment.
Reported-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
Fixes: 2aa349f6e37c ("[PATCH] Keys: Export user-defined keyring operations")
Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Tested-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: James Morris <james.morris@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/keys/user-type.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/keys/user-type.h
+++ b/include/keys/user-type.h
@@ -31,7 +31,7 @@
struct user_key_payload {
struct rcu_head rcu; /* RCU destructor */
unsigned short datalen; /* length of this data */
- char data[0]; /* actual data */
+ char data[0] __aligned(__alignof__(u64)); /* actual data */
};
extern struct key_type key_type_user;
