linux-stable/rust/bindings/bindings_helper.h
Boqun Feng b3d8aa84bb rust: allocator: Prevent mis-aligned allocation
Currently the rust allocator simply passes the size of the type Layout
to krealloc(), and in theory the alignment requirement from the type
Layout may be larger than the guarantee provided by SLAB, which means
the allocated object is mis-aligned.

Fix this by adjusting the allocation size to the nearest power of two,
which SLAB always guarantees a size-aligned allocation. And because Rust
guarantees that the original size must be a multiple of alignment and
the alignment must be a power of two, then the alignment requirement is
satisfied.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Co-developed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Signed-off-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Cc: stable@vger.kernel.org # v6.1+
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 247b365dc8 ("rust: add `kernel` crate")
Link: https://github.com/Rust-for-Linux/linux/issues/974
Link: https://lore.kernel.org/r/20230730012905.643822-2-boqun.feng@gmail.com
[ Applied rewording of comment as discussed in the mailing list. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-04 17:10:31 +02:00

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C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Header that contains the code (mostly headers) for which Rust bindings
* will be automatically generated by `bindgen`.
*
* Sorted alphabetically.
*/
#include <linux/errname.h>
#include <linux/slab.h>
#include <linux/refcount.h>
#include <linux/wait.h>
#include <linux/sched.h>
/* `bindgen` gets confused at certain things. */
const size_t BINDINGS_ARCH_SLAB_MINALIGN = ARCH_SLAB_MINALIGN;
const gfp_t BINDINGS_GFP_KERNEL = GFP_KERNEL;
const gfp_t BINDINGS___GFP_ZERO = __GFP_ZERO;