CVE-2024-43824: PCI: endpoint: pci-epf-test: Make use of cached 'epc_features' in pci_epf_test_core_init()

Vulnerability summary

CVE-2024-43824 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 19.3% of scored vulnerabilities.

Timeline

1. 17-08-2024
   PublishedVulnerability first disclosed.
2. 30-10-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-epf-test: Make use of cached 'epc_features' in pci_epf_test_core_init() Instead of getting the epc_features from pci_epc_get_features() API, use the cached pci_epf_test::epc_features value to avoid the NULL check. Since the NULL check is already performed in pci_epf_test_bind(), having one more check in pci_epf_test_core_init() is redundant and it is not possible to hit the NULL pointer dereference. Also with commit a01e7214bef9 ("PCI: endpoint: Remove "core_init_notifier" flag"), 'epc_features' got dereferenced without the NULL check, leading to the following false positive Smatch warning: drivers/pci/endpoint/functions/pci-epf-test.c:784 pci_epf_test_core_init() error: we previously assumed 'epc_features' could be null (see line 747) Thus, remove the redundant NULL check and also use the epc_features:: {msix_capable/msi_capable} flags directly to avoid local variables. [kwilczynski: commit log]

• CWE-476NULL Pointer DereferenceThe product dereferences a pointer that it expects to be valid but is NULL.