[Linux-kernel-mentees] [PATCH 3/14 v3] ath9k: Check the return value of pcie_capability_read_*()
From: Saheed O. Bolarinwa <hidden>
Date: 2020-07-13 16:55:28
Also in:
linux-pci, linux-wireless, lkml, netdev
Subsystem:
atheros ath generic utilities, qualcomm atheros ath9k wireless driver, the rest · Maintainers:
Jeff Johnson, Toke Høiland-Jørgensen, Linus Torvalds
From: Bolarinwa Olayemi Saheed <redacted> 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 <redacted> Signed-off-by: Bolarinwa Olayemi Saheed <redacted> --- 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 f3461b193c7a..cff9af3af38d 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);
--
2.18.2
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees