From: David Howells Date: Mon, 22 Oct 2012 14:05:48 +0000 (+0100) Subject: MODSIGN: Don't use enum-type bitfields in module signature info block X-Git-Tag: v3.7~14^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=12e130b04580532aa099893158aa2776b321ae7f;p=profile%2Fcommon%2Fkernel-common.git MODSIGN: Don't use enum-type bitfields in module signature info block Don't use enum-type bitfields in the module signature info block as we can't be certain how the compiler will handle them. As I understand it, it is arch dependent, and it is possible for the compiler to rearrange them based on endianness and to insert a byte of padding to pad the three enums out to four bytes. Instead use u8 fields for these, which the compiler should emit in the right order without padding. Signed-off-by: David Howells Signed-off-by: Rusty Russell --- diff --git a/kernel/module_signing.c b/kernel/module_signing.c index ea1b1df..f2970bd 100644 --- a/kernel/module_signing.c +++ b/kernel/module_signing.c @@ -27,13 +27,13 @@ * - Information block */ struct module_signature { - enum pkey_algo algo : 8; /* Public-key crypto algorithm */ - enum pkey_hash_algo hash : 8; /* Digest algorithm */ - enum pkey_id_type id_type : 8; /* Key identifier type */ - u8 signer_len; /* Length of signer's name */ - u8 key_id_len; /* Length of key identifier */ - u8 __pad[3]; - __be32 sig_len; /* Length of signature data */ + u8 algo; /* Public-key crypto algorithm [enum pkey_algo] */ + u8 hash; /* Digest algorithm [enum pkey_hash_algo] */ + u8 id_type; /* Key identifier type [enum pkey_id_type] */ + u8 signer_len; /* Length of signer's name */ + u8 key_id_len; /* Length of key identifier */ + u8 __pad[3]; + __be32 sig_len; /* Length of signature data */ }; /*