fix: Validate return value of get_slice in VolatileMemory functions #251
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kalyazin
requested review from
alexandruag,
bonzini,
jiangliu and
roypat
as code owners
roypat
approved these changes
Aug 29, 2023
An issue was discovered in the default implementations of the
VolatileMemory::{get_atomic_ref, aligned_as_ref, aligned_as_mut,
get_ref, get_array_ref} trait functions, which allows out-of-bounds
memory access if the VolatileMemory::get_slice function returns a
VolatileSlice whose length is less than the function’s count argument.
No implementations of get_slice provided in vm_memory are affected.
Users of custom VolatileMemory implementations may be impacted if the
custom implementation does not adhere to get_slice's documentation.
This commit fixes this issue by inserting a check that verifies that the
VolatileSlice returned by get_slice is of the correct length.
Signed-off-by: Patrick Roy <[email protected]>
roypat
approved these changes
Aug 29, 2023
JonathanWoollett-Light
approved these changes
Aug 29, 2023
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Summary of the PR
An issue was discovered in the default implementations of the VolatileMemory::{get_atomic_ref, aligned_as_ref, aligned_as_mut, get_ref, get_array_ref} trait functions, which allows out-of-bounds memory access if the VolatileMemory::get_slice function returns a VolatileSlice whose length is less than the function’s count argument. No implementations of get_slice provided in vm_memory are affected. Users of custom VolatileMemory implementations may be impacted if the custom implementation does not adhere to get_slice's documentation.
This commit fixes this issue by inserting a check that verifies that the VolatileSlice returned by get_slice is of the correct length.
Requirements
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git commit -s), and the commitmessage has max 60 characters for the summary and max 75 characters for each
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test.
Release" section of CHANGELOG.md (if no such section exists, please create one).
unsafecode is properly documented.