Re: [PATCH] PCI/proc: Use file_ns_capable() when checking config space read access

[sashiko-bot@kernel.org]

> 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
> [ ... ]
> As a result, a file descriptor opened by a privileged process and
> passed to an unprivileged one now allows the entire config space to
> be read through procfs, matching sysfs.
> 
> Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260720204145.1500105-1-kwilczynski@kernel.org?part=1