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Gary noticed [1] that the initializer macros as well as the `[Pin]Init` traits cannot support packed struct, since they use operations that require aligned pointers. This means that any code using packed structs and pin-init is unsound. Thus remove the `#[disable_initialized_field_access]` attribute from `init!`, which is the only safe way to create an initializer of a packed struct. In the future, we can add support for packed structs by changing the trait infrastructure to include `UnalignedInit` or hopefully another mechanism. Reported-by: Gary Guo <gary@garyguo.net> Link: https://rust-for-linux.zulipchat.com/#narrow/channel/561532-pin-init/topic/initialized.20field.20accessor.20detection/with/576210658 [1] Fixes: db96c51 ("add references to previously initialized fields") Signed-off-by: Benno Lossin <lossin@kernel.org>
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The commit that this fixes should be the one that introduced this feature instead? Arguably creating reference is the fix, not the fixed commit. |
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Gary noticed [1] that the initializer macros as well as the
[Pin]Inittraits cannot support packed struct, since they use operations that require aligned pointers. This means that any code using packed structs and pin-init is unsound.Thus remove the
#[disable_initialized_field_access]attribute frominit!, which is the only safe way to create an initializer of a packed struct.In the future, we can add support for packed structs by changing the trait infrastructure to include
UnalignedInitor hopefully another mechanism.Reported-by: Gary Guo gary@garyguo.net
Link: https://rust-for-linux.zulipchat.com/#narrow/channel/561532-pin-init/topic/initialized.20field.20accessor.20detection/with/576210658 [1]
Fixes: db96c51 ("add references to previously initialized fields")