[PATCH AUTOSEL 5.15 03/23] PCI: tegra194: Fix possible array out of bounds access
From: Sasha Levin <sashal@kernel.org>
Date: 2023-07-24 01:26:29
Also in:
linux-pci, linux-tegra, lkml
Subsystem:
pci native host bridge and endpoint drivers, pci subsystem, the rest · Maintainers:
Lorenzo Pieralisi, Krzysztof Wilczyński, Manivannan Sadhasivam, Bjorn Helgaas, Linus Torvalds
From: Sumit Gupta <sumitg@nvidia.com> [ Upstream commit 205b3d02d57ce6dce96f6d2b9c230f56a9bf9817 ] Add check to fix the possible array out of bounds violation by making speed equal to GEN1_CORE_CLK_FREQ when its value is more than the size of "pcie_gen_freq" array. This array has size of four but possible speed (CLS) values are from "0 to 0xF". So, "speed - 1" values are "-1 to 0xE". Suggested-by: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Sumit Gupta <sumitg@nvidia.com> Link: https://lore.kernel.org/lkml/72b9168b-d4d6-4312-32ea-69358df2f2d0@nvidia.com/ (local) Acked-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Signed-off-by: Thierry Reding <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/pci/controller/dwc/pcie-tegra194.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index bdd84765e6460..765abe0732282 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c@@ -239,6 +239,7 @@ #define EP_STATE_ENABLED 1 static const unsigned int pcie_gen_freq[] = { + GEN1_CORE_CLK_FREQ, /* PCI_EXP_LNKSTA_CLS == 0; undefined */ GEN1_CORE_CLK_FREQ, GEN2_CORE_CLK_FREQ, GEN3_CORE_CLK_FREQ,
@@ -452,7 +453,11 @@ static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg) speed = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKSTA) & PCI_EXP_LNKSTA_CLS; - clk_set_rate(pcie->core_clk, pcie_gen_freq[speed - 1]); + + if (speed >= ARRAY_SIZE(pcie_gen_freq)) + speed = 0; + + clk_set_rate(pcie->core_clk, pcie_gen_freq[speed]); /* If EP doesn't advertise L1SS, just return */ val = dw_pcie_readl_dbi(pci, pcie->cfg_link_cap_l1sub);
@@ -989,7 +994,11 @@ static int tegra_pcie_dw_start_link(struct dw_pcie *pci) speed = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKSTA) & PCI_EXP_LNKSTA_CLS; - clk_set_rate(pcie->core_clk, pcie_gen_freq[speed - 1]); + + if (speed >= ARRAY_SIZE(pcie_gen_freq)) + speed = 0; + + clk_set_rate(pcie->core_clk, pcie_gen_freq[speed]); tegra_pcie_enable_interrupts(pp);
--
2.39.2