[PATCH 4/14 v3] iwlegacy: Check the return value of pcie_capability_read_*()
From: Saheed O. Bolarinwa <hidden>
Date: 2020-07-13 16:55:32
Also in:
linux-kernel-mentees, linux-pci, lkml, netdev
Subsystem:
intel wireless 3945abg/bg, 4965agn (iwlegacy), the rest · Maintainers:
Stanislaw Gruszka, Linus Torvalds
Possibly related (same subject, not in this thread)
- 2020-07-13 · Re: [PATCH 4/14 v3] iwlegacy: Check the return value of pcie_capability_read_*() · Saheed Bolarinwa <hidden>
- 2020-07-13 · Re: [PATCH 4/14 v3] iwlegacy: Check the return value of pcie_capability_read_*() · Kalle Valo <hidden>
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/intel/iwlegacy/common.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlegacy/common.c b/drivers/net/wireless/intel/iwlegacy/common.c
index 348c17ce72f5..f78e062df572 100644
--- a/drivers/net/wireless/intel/iwlegacy/common.c
+++ b/drivers/net/wireless/intel/iwlegacy/common.c@@ -4286,8 +4286,8 @@ il_apm_init(struct il_priv *il) * power savings, even without L1. */ if (il->cfg->set_l0s) { - pcie_capability_read_word(il->pci_dev, PCI_EXP_LNKCTL, &lctl); - if (lctl & PCI_EXP_LNKCTL_ASPM_L1) { + ret = pcie_capability_read_word(il->pci_dev, PCI_EXP_LNKCTL, &lctl); + if (!ret && (lctl & PCI_EXP_LNKCTL_ASPM_L1)) { /* L1-ASPM enabled; disable(!) L0S */ il_set_bit(il, CSR_GIO_REG, CSR_GIO_REG_VAL_L0S_ENABLED);
--
2.18.2