From 9a8ab2bfb678193f326239143290691c965faede Mon Sep 17 00:00:00 2001 From: Bolarinwa Olayemi Saheed Date: Mon, 13 Jul 2020 19:55:26 +0200 Subject: [PATCH] ath9k: Check the return value of pcie_capability_read_*() On failure pcie_capability_read_dword() sets it's last parameter, val to 0. However, with Patch 14/14, it is possible that val is set to ~0 on failure. This would introduce a bug because (x & x) == (~0 & x). This bug can be avoided without changing the function's behaviour if the return value of pcie_capability_read_dword is checked to confirm success. Check the return value of pcie_capability_read_dword() to ensure success. Suggested-by: Bjorn Helgaas Signed-off-by: Bolarinwa Olayemi Saheed Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20200713175529.29715-2-refactormyself@gmail.com --- drivers/net/wireless/ath/ath9k/pci.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c index f3461b1..cff9af3 100644 --- a/drivers/net/wireless/ath/ath9k/pci.c +++ b/drivers/net/wireless/ath/ath9k/pci.c @@ -825,6 +825,7 @@ static void ath_pci_aspm_init(struct ath_common *common) struct pci_dev *pdev = to_pci_dev(sc->dev); struct pci_dev *parent; u16 aspm; + int ret; if (!ah->is_pciexpress) return; @@ -866,8 +867,8 @@ static void ath_pci_aspm_init(struct ath_common *common) if (AR_SREV_9462(ah)) pci_read_config_dword(pdev, 0x70c, &ah->config.aspm_l1_fix); - pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &aspm); - if (aspm & (PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1)) { + ret = pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &aspm); + if (!ret && (aspm & (PCI_EXP_LNKCTL_ASPM_L0S | PCI_EXP_LNKCTL_ASPM_L1))) { ah->aspm_enabled = true; /* Initialize PCIe PM and SERDES registers. */ ath9k_hw_configpcipowersave(ah, false); -- 2.7.4