From: Songyang Li leesongyang@outlook.com

mainline inclusion from mainline-v6.10-rc1 commit 29b83a64df3b42c88c0338696feb6fdcd7f1f3b7 category: bugfix bugzilla: 190183 CVE: CVE-2024-40968

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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The standard PCIe configuration read-write interface is used to access the configuration space of the peripheral PCIe devices of the mips processor after the PCIe link surprise down, it can generate kernel panic caused by "Data bus error". So it is necessary to add PCIe link status check for system protection. When the PCIe link is down or in training, assigning a value of 0 to the configuration address can prevent read-write behavior to the configuration space of peripheral PCIe devices, thereby preventing kernel panic.

Signed-off-by: Songyang Li leesongyang@outlook.com Signed-off-by: Thomas Bogendoerfer tsbogend@alpha.franken.de Signed-off-by: Liao Chen liaochen4@huawei.com --- arch/mips/pci/pcie-octeon.c | 6 ++++++ 1 file changed, 6 insertions(+) mode change 100644 => 100755 arch/mips/pci/pcie-octeon.c

diff --git a/arch/mips/pci/pcie-octeon.c b/arch/mips/pci/pcie-octeon.c old mode 100644 new mode 100755 index d919a0d813a1..38de2a9c3cf1 --- a/arch/mips/pci/pcie-octeon.c +++ b/arch/mips/pci/pcie-octeon.c @@ -230,12 +230,18 @@ static inline uint64_t __cvmx_pcie_build_config_addr(int pcie_port, int bus, { union cvmx_pcie_address pcie_addr; union cvmx_pciercx_cfg006 pciercx_cfg006; + union cvmx_pciercx_cfg032 pciercx_cfg032;

pciercx_cfg006.u32 = cvmx_pcie_cfgx_read(pcie_port, CVMX_PCIERCX_CFG006(pcie_port)); if ((bus <= pciercx_cfg006.s.pbnum) && (dev != 0)) return 0;

+ pciercx_cfg032.u32 = + cvmx_pcie_cfgx_read(pcie_port, CVMX_PCIERCX_CFG032(pcie_port)); + if ((pciercx_cfg032.s.dlla == 0) || (pciercx_cfg032.s.lt == 1)) + return 0; + pcie_addr.u64 = 0; pcie_addr.config.upper = 2; pcie_addr.config.io = 1;