vulkan: Don't use pointer to dropped PhysicalDeviceDriverProperties. #3076
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jimblandy
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jimblandy
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type: bug
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We could avoid those |
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cwfitzgerald
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Oct 6, 2022
Detected by ASAN, but seems impossible to exploit.
Since `ash::vk::definitions::PhysicalDeviceDriverProperties` is
`Copy`, the statement
if let Some(driver) = phd_capabilities.driver { ... }
actually makes `driver` a local copy of the struct. The code uses
`as_ptr` to create a pointer to the `driver_name` field of this local
copy, and then tries to use that pointer outside the `if let`, when
the local copy has gone out of scope. This is UB.
Taking a reference to the properties struct is correct and more
efficient.
Remove a handful of `unsafe` blocks from the Vulkan back end.
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CI is mad |
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Detected by ASAN, but seems impossible to exploit.
Since
ash::vk::definitions::PhysicalDeviceDriverPropertiesisCopy, the statementactually makes
drivera local copy of the struct. The code usesas_ptrto create a pointer to thedriver_namefield of this local copy, and then tries to use that pointer outside theif let, when the local copy has gone out of scope. This is UB.Taking a reference to the properties struct is correct and more efficient.
Checklist
cargo clippy.RUSTFLAGS=--cfg=web_sys_unstable_apis cargo clippy --target wasm32-unknown-unknownif applicable.Connections
Link to the issues addressed by this PR, or dependent PRs in other repositories
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