fix(api): Check if pointer is aligned before reading #5449
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✅ No documentation updates required. |
syrusakbary
approved these changes
Mar 3, 2025
charmitro
reviewed
Mar 3, 2025
Comment on lines
+109
to
+113
| let buf_ptr = out.as_mut_ptr() as *mut u8; | ||
| if !buf_ptr.is_aligned() { | ||
| return Err(MemoryAccessError::UnalignedPointer); | ||
| } | ||
| let buf = unsafe { slice::from_raw_parts_mut(buf_ptr, mem::size_of::<T>()) }; |
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Isn't .is_aligned() always going to return true due to this?
MaybeUninit is guaranteed to have the same size, alignment, and ABI as T:
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Depends... These guarantees only hold as long as we don't have unsafe code, and we do have a lot of unsafe code near the syscall boundaries. Still, @xdoardo would know better.
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But also, since we're casting to *mut u8... Let's add a test?
Arshia001
requested changes
Mar 3, 2025
Comment on lines
+109
to
+113
| let buf_ptr = out.as_mut_ptr() as *mut u8; | ||
| if !buf_ptr.is_aligned() { | ||
| return Err(MemoryAccessError::UnalignedPointer); | ||
| } | ||
| let buf = unsafe { slice::from_raw_parts_mut(buf_ptr, mem::size_of::<T>()) }; |
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But also, since we're casting to *mut u8... Let's add a test?
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As per title. Fixes #5444