2 Commits

Author	SHA1	Message	Date
Boqun Feng	f0618c305b	rust: allocator: Prevent mis-aligned allocation ... commit b3d8aa84bbfe9b58ccc5332cacf8ea17200af310 upstream. 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: 247b365dc8dc ("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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>	2023-08-11 12:08:18 +02:00
Miguel Ojeda	8326ac05ee	rust: add bindings crate ... This crate contains the bindings to the C side of the kernel. Calling C (in general, FFI) is assumed to be unsafe in Rust and, in many cases, this is accurate. For instance, virtually all C functions that take a pointer are unsafe since, typically, it will be dereferenced at some point (and in most cases there is no way for the callee to check its validity beforehand). Since one of the goals of using Rust in the kernel is precisely to avoid unsafe code in "leaf" kernel modules (e.g. drivers), these bindings should not be used directly by them. Instead, these bindings need to be wrapped into safe abstractions. These abstractions provide a safe API that kernel modules can use. In this way, unsafe code in kernel modules is minimized. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com> Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com> Co-developed-by: Finn Behrens <me@kloenk.de> Signed-off-by: Finn Behrens <me@kloenk.de> Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com> Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com> Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com> Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Co-developed-by: Maciej Falkowski <m.falkowski@samsung.com> Signed-off-by: Maciej Falkowski <m.falkowski@samsung.com> Co-developed-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>	2022-09-28 08:58:00 +02:00