| Message ID | 20190115033716.18380-1-ebiggers@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | KEYS: user: Align the payload buffer | expand |
Hi, On Mon, Jan 14, 2019 at 07:37:16PM -0800, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > 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@iki.fi> > Fixes: 2aa349f6e37c ("[PATCH] Keys: Export user-defined keyring operations") > Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities") > Cc: stable@vger.kernel.org > Signed-off-by: Eric Biggers <ebiggers@google.com> Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi> This fixes the "unaligned access" dmesg spam on SPARC when using ext4 encryption. Thanks, A. > --- > include/keys/user-type.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/keys/user-type.h b/include/keys/user-type.h > index e098cbe27db54..12babe9915944 100644 > --- 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; > -- > 2.20.1 >
On Mon, Jan 14, 2019 at 07:37:16PM -0800, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > 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@iki.fi> > Fixes: 2aa349f6e37c ("[PATCH] Keys: Export user-defined keyring operations") > Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities") > Cc: stable@vger.kernel.org > Signed-off-by: Eric Biggers <ebiggers@google.com> > --- > include/keys/user-type.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/keys/user-type.h b/include/keys/user-type.h > index e098cbe27db54..12babe9915944 100644 > --- 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; > -- > 2.20.1 > Ping. David, are you planning to apply this? - Eric
On Thu, Feb 07, 2019 at 03:35:09PM -0800, Eric Biggers wrote: > On Mon, Jan 14, 2019 at 07:37:16PM -0800, Eric Biggers wrote: > > From: Eric Biggers <ebiggers@google.com> > > > > 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@iki.fi> > > Fixes: 2aa349f6e37c ("[PATCH] Keys: Export user-defined keyring operations") > > Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities") > > Cc: stable@vger.kernel.org > > Signed-off-by: Eric Biggers <ebiggers@google.com> > > --- > > include/keys/user-type.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/include/keys/user-type.h b/include/keys/user-type.h > > index e098cbe27db54..12babe9915944 100644 > > --- 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; > > -- > > 2.20.1 > > > > Ping. David, are you planning to apply this? > > - Eric Ping.
Sent on to James. David
diff --git a/include/keys/user-type.h b/include/keys/user-type.h index e098cbe27db54..12babe9915944 100644 --- 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;