Bug 2256561 (CVE-2023-50711)

Summary: CVE-2023-50711 vmm-sys-util: out of bounds memory accesses
Product: [Other] Security Response Reporter: Rohit Keshri <rkeshri>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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vmm-sys-util is a collection of modules that provides helpers and utilities used by multiple rust-vmm components. Starting in version 0.5.0 and prior to version 0.12.0, an issue in the `FamStructWrapper::deserialize` implementation provided by the crate for `vmm_sys_util::fam::FamStructWrapper` can lead to out of bounds memory accesses. The deserialization does not check that the length stored in the header matches the flexible array length. Mismatch in the lengths might allow out of bounds memory access through Rust-safe methods. The issue was corrected in version 0.12.0 by inserting a check that verifies the lengths of compared flexible arrays are equal for any deserialized header and aborting deserialization otherwise. Moreover, the API was changed so that header length can only be modified through Rust-unsafe code. This ensures that users cannot trigger out-of-bounds memory access from Rust-safe code.
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Bug Depends On: 2256562    
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Description Rohit Keshri 2024-01-03 05:13:17 UTC 
vmm-sys-util is a collection of modules that provides helpers and utilities used by multiple rust-vmm components. Starting in version 0.5.0 and prior to version 0.12.0, an issue in the `FamStructWrapper::deserialize` implementation provided by the crate for `vmm_sys_util::fam::FamStructWrapper` can lead to out of bounds memory accesses. The deserialization does not check that the length stored in the header matches the flexible array length. Mismatch in the lengths might allow out of bounds memory access through Rust-safe methods. The issue was corrected in version 0.12.0 by inserting a check that verifies the lengths of compared flexible arrays are equal for any deserialized header and aborting deserialization otherwise. Moreover, the API was changed so that header length can only be modified through Rust-unsafe code. This ensures that users cannot trigger out-of-bounds memory access from Rust-safe code.

https://github.com/rust-vmm/vmm-sys-util/commit/30172fca2a8e0a38667d934ee56682247e13f167
https://github.com/rust-vmm/vmm-sys-util/security/advisories/GHSA-875g-mfp6-g7f9
Comment 1 Rohit Keshri 2024-01-03 05:17:48 UTC 
Created rust-vmm-sys-util tracking bugs for this issue:

Affects: fedora-all [bug 2256562]