mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-05 18:41:58 +09:00
7aecdd4791
[ Upstream commit456d8aa37d] Struct pcie_link_state->downstream is a pointer to the pci_dev of function 0. Previously we retained that pointer when removing function 0, and subsequent ASPM policy changes dereferenced it, resulting in a use-after-free warning from KASAN, e.g.: # echo 1 > /sys/bus/pci/devices/0000:03:00.0/remove # echo powersave > /sys/module/pcie_aspm/parameters/policy BUG: KASAN: slab-use-after-free in pcie_config_aspm_link+0x42d/0x500 Call Trace: kasan_report+0xae/0xe0 pcie_config_aspm_link+0x42d/0x500 pcie_aspm_set_policy+0x8e/0x1a0 param_attr_store+0x162/0x2c0 module_attr_store+0x3e/0x80 PCIe spec r6.0, sec 7.5.3.7, recommends that software program the same ASPM Control value in all functions of multi-function devices. Disable ASPM and free the pcie_link_state when any child function is removed so we can discard the dangling pcie_link_state->downstream pointer and maintain the same ASPM Control configuration for all functions. [bhelgaas: commit log and comment] Debugged-by: Zongquan Qin <qinzongquan@sangfor.com.cn> Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Fixes:b5a0a9b59c("PCI/ASPM: Read and set up L1 substate capabilities") Link: https://lore.kernel.org/r/20230507034057.20970-1-dinghui@sangfor.com.cn Signed-off-by: Ding Hui <dinghui@sangfor.com.cn> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.