diff mbox series

afs: Annotate struct afs_permits with __counted_by

Message ID 20230915201456.never.529-kees@kernel.org
State New
Headers
Series afs: Annotate struct afs_permits with __counted_by |

Commit Message

Kees Cook Sept. 15, 2023, 8:14 p.m. UTC 
  Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct afs_permits.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 fs/afs/internal.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Kees Cook Sept. 29, 2023, 7:17 p.m. UTC | #1 
On Fri, 15 Sep 2023 13:14:56 -0700, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
> 
> As found with Coccinelle[1], add __counted_by for struct afs_permits.
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] afs: Annotate struct afs_permits with __counted_by
      https://git.kernel.org/kees/c/45faff97751a

Take care,
diff mbox series

Patch

diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 07433a5349ca..469a717467a4 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -705,7 +705,7 @@  struct afs_permits {
 	refcount_t		usage;
 	unsigned short		nr_permits;	/* Number of records */
 	bool			invalidated;	/* Invalidated due to key change */
-	struct afs_permit	permits[];	/* List of permits sorted by key pointer */
+	struct afs_permit	permits[] __counted_by(nr_permits);	/* List of permits sorted by key pointer */
 };
 
 /*