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e78e274eb2
When built with Control Flow Integrity, function prototypes between
caller and function declaration must match. These mismatches are visible
at compile time with the new -Wcast-function-type-strict in Clang[1].
There were 97 warnings produced by NFS. For example:
fs/nfsd/nfs4xdr.c:2228:17: warning: cast from '__be32 (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)') to 'nfsd4_dec' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, void *)') converts to incompatible function type [-Wcast-function-type-strict]
[OP_ACCESS] = (nfsd4_dec)nfsd4_decode_access,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The enc/dec callbacks were defined as passing "void *" as the second
argument, but were being implicitly cast to a new type. Replace the
argument with union nfsd4_op_u, and perform explicit member selection
in the function body. There are no resulting binary differences.
Changes were made mechanically using the following Coccinelle script,
with minor by-hand fixes for members that didn't already match their
existing argument name:
@find@
identifier func;
type T, opsT;
identifier ops, N;
@@
opsT ops[] = {
[N] = (T) func,
};
@already_void@
identifier find.func;
identifier name;
@@
func(...,
-void
+union nfsd4_op_u
*name)
{
...
}
@proto depends on !already_void@
identifier find.func;
type T;
identifier name;
position p;
@@
func@p(...,
T name
) {
...
}
@script:python get_member@
type_name << proto.T;
member;
@@
coccinelle.member = cocci.make_ident(type_name.split("_", 1)[1].split(' ',1)[0])
@convert@
identifier find.func;
type proto.T;
identifier proto.name;
position proto.p;
identifier get_member.member;
@@
func@p(...,
- T name
+ union nfsd4_op_u *u
) {
+ T name = &u->member;
...
}
@cast@
identifier find.func;
type T, opsT;
identifier ops, N;
@@
opsT ops[] = {
[N] =
- (T)
func,
};
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
|
||
|---|---|---|
| .. | ||
| acl.h | ||
| auth.c | ||
| auth.h | ||
| blocklayout.c | ||
| blocklayoutxdr.c | ||
| blocklayoutxdr.h | ||
| cache.h | ||
| current_stateid.h | ||
| export.c | ||
| export.h | ||
| fault_inject.c | ||
| filecache.c | ||
| filecache.h | ||
| flexfilelayout.c | ||
| flexfilelayoutxdr.c | ||
| flexfilelayoutxdr.h | ||
| idmap.h | ||
| Kconfig | ||
| lockd.c | ||
| Makefile | ||
| netns.h | ||
| nfs2acl.c | ||
| nfs3acl.c | ||
| nfs3proc.c | ||
| nfs3xdr.c | ||
| nfs4acl.c | ||
| nfs4callback.c | ||
| nfs4idmap.c | ||
| nfs4layouts.c | ||
| nfs4proc.c | ||
| nfs4recover.c | ||
| nfs4state.c | ||
| nfs4xdr.c | ||
| nfscache.c | ||
| nfsctl.c | ||
| nfsd.h | ||
| nfsfh.c | ||
| nfsfh.h | ||
| nfsproc.c | ||
| nfssvc.c | ||
| nfsxdr.c | ||
| pnfs.h | ||
| state.h | ||
| stats.c | ||
| stats.h | ||
| trace.c | ||
| trace.h | ||
| vfs.c | ||
| vfs.h | ||
| xdr3.h | ||
| xdr4.h | ||
| xdr4cb.h | ||
| xdr.h | ||