CVE-2026-93206
In the Linux kernel, the following vulnerability has been resolved: PCI/proc: Use file_ns_capable() when checking config space read access proc_bus_pci_read() decides how much of the config space is readable based on capable(CAP_SYS_ADMIN), which checks the credentials of the task calling read(), not the credentials of the process that opened the file. The sysfs equivalent, pci_read_config(), has checked the credentials of the opening process since commit de139a339395 ("pci: check caps from sysfs file open to read device dependent config space"), so a privileged process can open the config space file and pass the file descriptor to an unprivileged process (for example, a process running a KVM guest with an assigned device), which can then read the entire config space. The check was subsequently routed through the LSM framework in commit 47970b1b2aa6 ("pci: use security_capable() when checking capablities during config space read") and converted to the dedicated helper in commit ab0fa82b2df9 ("pci-sysfs: use proper file capability helper function"). Thus, the two interfaces check the same capability against different credentials. Checking the credentials of the task calling read() m
脆弱性の種類
In the Linux kernel, the following vulnerability has been resolved: PCI/proc: Use file_ns_capable() when checking config space read access proc_bus_pci_read() decides how much of the config space is readable based on capable(CAP_SYS_ADMIN), which checks the credentials of the task calling read(), not the credentials of the process that opened the file. The sysfs equivalent, pci_read_config(), has checked the credentials of the opening process since commit de139a339395 ("pci: check caps from sysfs file open to read device dependent config space"), so a privileged process can open the config space file and pass the file descriptor to an unprivileged process (for example, a process running a KVM guest with an assigned device), which can then read the entire config space. The check was subsequently routed through the LSM framework in commit 47970b1b2aa6 ("pci: use security_capable() when checking capablities during config space read") and converted to the dedicated helper in commit ab0fa82b2df9 ("pci-sysfs: use proper file capability helper function"). Thus, the two interfaces check the same capability against different credentials. Checking the credentials of the task calling read() m
参考情報
- https://git.kernel.org/stable/c/53407535d49ec034e476121020b5c878f0d92e18
- https://git.kernel.org/stable/c/5c7ab4ca66f0880cffc3735555ea719dd5253726
- https://git.kernel.org/stable/c/6351e94076329dab517ea94c115e15c4d8459381
- https://git.kernel.org/stable/c/77272b7fd0e472086fd626a1fcd11da625822cc2
- https://git.kernel.org/stable/c/8a3a54aa3e65ed76f8560a387243a7738ae0cb1c
- https://git.kernel.org/stable/c/c2d4174f492458ecdcdef309243624999612d526