CVE-2023-53315

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath11k: Fix SKB corruption in REO destination ring

While running traffics for a long time, randomly an RX descriptor filled with value 0 from REO destination ring is received. This descriptor which is invalid causes the wrong SKB (SKB stored in the IDR lookup with buffer id 0) to be fetched which in turn causes SKB memory corruption issue and the same leads to crash after some time.

Changed the start id for idr allocation to 1 and the buffer id 0 is reserved for error validation. Introduced Sanity check to validate the descriptor, before processing the SKB.

Crash Signature :

Unable to handle kernel paging request at virtual address 3f004900 PC points to b15_dma_inv_range+0x30/0x50 LR points to dma_cache_maint_page+0x8c/0x128. The Backtrace obtained is as follows: [<8031716c>] (b15_dma_inv_range) from [<80313a4c>] (dma_cache_maint_page+0x8c/0x128) [<80313a4c>] (dma_cache_maint_page) from [<80313b90>] (__dma_page_dev_to_cpu+0x28/0xcc) [<80313b90>] (__dma_page_dev_to_cpu) from [<7fb5dd68>] (ath11k_dp_process_rx+0x1e8/0x4a4 [ath11k]) [<7fb5dd68>] (ath11k_dp_process_rx [ath11k]) from [<7fb53c20>] (ath11k_dp_service_srng+0xb0/0x2ac [ath11k]) [<7fb53c20>] (ath11k_dp_service_srng [ath11k]) from [<7f67bba4>] (ath11k_pci_ext_grp_napi_poll+0x1c/0x78 [ath11k_pci]) [<7f67bba4>] (ath11k_pci_ext_grp_napi_poll [ath11k_pci]) from [<807d5cf4>] (__napi_poll+0x28/0xb8) [<807d5cf4>] (__napi_poll) from [<807d5f28>] (net_rx_action+0xf0/0x280) [<807d5f28>] (net_rx_action) from [<80302148>] (__do_softirq+0xd0/0x280) [<80302148>] (__do_softirq) from [<80320408>] (irq_exit+0x74/0xd4) [<80320408>] (irq_exit) from [<803638a4>] (__handle_domain_irq+0x90/0xb4) [<803638a4>] (__handle_domain_irq) from [<805bedec>] (gic_handle_irq+0x58/0x90) [<805bedec>] (gic_handle_irq) from [<80301a78>] (__irq_svc+0x58/0x8c)

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1

Weakness

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/068fd06148fbf0af95bb08dc77cff34ee679fdbc
• https://git.kernel.org/stable/c/3d3f8fe01a01d94a17fe1ae0d2e894049a972717
• https://git.kernel.org/stable/c/67459491f78146bcf7d93596e5b709d063dff5d8
• https://git.kernel.org/stable/c/866921dc06b94df91acfcf9359b57da943ed99b3
• https://git.kernel.org/stable/c/f9fff67d2d7ca6fa8066132003a3deef654c55b1