[PATCH] phy: qcom-qmp: Ensure register indirection arrays initialized

From: Bjorn Andersson
Date: Thu May 14 2020 - 21:37:35 EST


It's possible that struct qmp_phy_cfg->regs references an array that is
smaller than the possible register lookups that is going to be
performed, with the resulting out-of-bounds read resulting in undefined
behavior.

One such example is when during qcom_qmp_phy_com_init() performs a
qphy_setbits() on entry QPHY_PCS_POWER_DOWN_CONTROL (i.e. 17) with
msm8996_ufsphy_regs_layout only being 12 entries long.

Solve this by inflating all "regs_layout" arrays to ensure that any
remaining entries are zero-initialized, as expected by the code.

Fixes: e4d8b05ad5f9 ("phy: qcom-qmp: Use proper PWRDOWN offset for sm8150 USB")
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
drivers/phy/qualcomm/phy-qcom-qmp.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
index 5942167320a3..c4bf5fd26fa0 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
@@ -120,14 +120,16 @@ enum qphy_reg_layout {
QPHY_PCS_LFPS_RXTERM_IRQ_CLEAR,
QPHY_PCS_LFPS_RXTERM_IRQ_STATUS,
QPHY_PCS_POWER_DOWN_CONTROL,
+ /* Keep last to ensure regs_layout arrays are properly initialized */
+ QPHY_LAYOUT_SIZE
};

-static const unsigned int msm8996_ufsphy_regs_layout[] = {
+static const unsigned int msm8996_ufsphy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_START_CTRL] = 0x00,
[QPHY_PCS_READY_STATUS] = 0x168,
};

-static const unsigned int pciephy_regs_layout[] = {
+static const unsigned int pciephy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_COM_SW_RESET] = 0x400,
[QPHY_COM_POWER_DOWN_CONTROL] = 0x404,
[QPHY_COM_START_CONTROL] = 0x408,
@@ -143,7 +145,7 @@ static const unsigned int pciephy_regs_layout[] = {
[QPHY_PCS_STATUS] = 0x174,
};

-static const unsigned int usb3phy_regs_layout[] = {
+static const unsigned int usb3phy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_FLL_CNTRL1] = 0xc0,
[QPHY_FLL_CNTRL2] = 0xc4,
[QPHY_FLL_CNT_VAL_L] = 0xc8,
@@ -157,7 +159,7 @@ static const unsigned int usb3phy_regs_layout[] = {
[QPHY_PCS_LFPS_RXTERM_IRQ_STATUS] = 0x178,
};

-static const unsigned int qmp_v3_usb3phy_regs_layout[] = {
+static const unsigned int qmp_v3_usb3phy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_SW_RESET] = 0x00,
[QPHY_START_CTRL] = 0x08,
[QPHY_PCS_STATUS] = 0x174,
@@ -166,31 +168,31 @@ static const unsigned int qmp_v3_usb3phy_regs_layout[] = {
[QPHY_PCS_LFPS_RXTERM_IRQ_STATUS] = 0x170,
};

-static const unsigned int sdm845_qmp_pciephy_regs_layout[] = {
+static const unsigned int sdm845_qmp_pciephy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_SW_RESET] = 0x00,
[QPHY_START_CTRL] = 0x08,
[QPHY_PCS_STATUS] = 0x174,
};

-static const unsigned int sdm845_qhp_pciephy_regs_layout[] = {
+static const unsigned int sdm845_qhp_pciephy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_SW_RESET] = 0x00,
[QPHY_START_CTRL] = 0x08,
[QPHY_PCS_STATUS] = 0x2ac,
};

-static const unsigned int qmp_v4_usb3phy_regs_layout[] = {
+static const unsigned int qmp_v4_usb3phy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_SW_RESET] = 0x00,
[QPHY_START_CTRL] = 0x44,
[QPHY_PCS_STATUS] = 0x14,
[QPHY_PCS_POWER_DOWN_CONTROL] = 0x40,
};

-static const unsigned int sdm845_ufsphy_regs_layout[] = {
+static const unsigned int sdm845_ufsphy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_START_CTRL] = 0x00,
[QPHY_PCS_READY_STATUS] = 0x160,
};

-static const unsigned int sm8150_ufsphy_regs_layout[] = {
+static const unsigned int sm8150_ufsphy_regs_layout[QPHY_LAYOUT_SIZE] = {
[QPHY_START_CTRL] = QPHY_V4_PCS_UFS_PHY_START,
[QPHY_PCS_READY_STATUS] = QPHY_V4_PCS_UFS_READY_STATUS,
[QPHY_SW_RESET] = QPHY_V4_PCS_UFS_SW_RESET,
--
2.26.2