| Message ID | 20190206014733.21094-1-yzhai003@ucr.edu (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | phy: Variable "caldone" in function rockchip_emmc_phy_power() could be uninitialized | expand |
Am Mittwoch, 6. Februar 2019, 02:47:33 CET schrieb Yizhuo: > In function rockchip_emmc_phy_power(), local variable "caldone" > could be uninitialized if function regmap_read() returns -EINVAL. > However, it will be used directly in the later context, which > is potentially unsafe. > > Signed-off-by: Yizhuo <yzhai003@ucr.edu> > --- > drivers/phy/rockchip/phy-rockchip-emmc.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c > b/drivers/phy/rockchip/phy-rockchip-emmc.c index f1b24f18e9b2..ca921ae08309 > 100644 > --- a/drivers/phy/rockchip/phy-rockchip-emmc.c > +++ b/drivers/phy/rockchip/phy-rockchip-emmc.c > @@ -85,11 +85,12 @@ struct rockchip_emmc_phy { > static int rockchip_emmc_phy_power(struct phy *phy, bool on_off) > { > struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); > - unsigned int caldone; > + unsigned int caldone = 0; hmm, this may hide actual uninitialized uses in the future? With the added error handling below, there shouldn't be a case where caldone might be used uninitialized still? Heiko > unsigned int dllrdy; > unsigned int freqsel = PHYCTRL_FREQSEL_200M; > unsigned long rate; > unsigned long timeout; > + int err; > > /* > * Keep phyctrl_pdb and phyctrl_endll low to allow > @@ -164,9 +165,14 @@ static int rockchip_emmc_phy_power(struct phy *phy, > bool on_off) * wait 5us for calpad busy trimming > */ > udelay(5); > - regmap_read(rk_phy->reg_base, > + err = regmap_read(rk_phy->reg_base, > rk_phy->reg_offset + GRF_EMMCPHY_STATUS, > &caldone); > + if (err) { > + pr_err("Failed to read status.\n"); > + return err; > + } > + > caldone = (caldone >> PHYCTRL_CALDONE_SHIFT) & PHYCTRL_CALDONE_MASK; > if (caldone != PHYCTRL_CALDONE_DONE) { > pr_err("rockchip_emmc_phy_power: caldone timeout.\n");
diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c index f1b24f18e9b2..ca921ae08309 100644 --- a/drivers/phy/rockchip/phy-rockchip-emmc.c +++ b/drivers/phy/rockchip/phy-rockchip-emmc.c @@ -85,11 +85,12 @@ struct rockchip_emmc_phy { static int rockchip_emmc_phy_power(struct phy *phy, bool on_off) { struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); - unsigned int caldone; + unsigned int caldone = 0; unsigned int dllrdy; unsigned int freqsel = PHYCTRL_FREQSEL_200M; unsigned long rate; unsigned long timeout; + int err; /* * Keep phyctrl_pdb and phyctrl_endll low to allow @@ -164,9 +165,14 @@ static int rockchip_emmc_phy_power(struct phy *phy, bool on_off) * wait 5us for calpad busy trimming */ udelay(5); - regmap_read(rk_phy->reg_base, + err = regmap_read(rk_phy->reg_base, rk_phy->reg_offset + GRF_EMMCPHY_STATUS, &caldone); + if (err) { + pr_err("Failed to read status.\n"); + return err; + } + caldone = (caldone >> PHYCTRL_CALDONE_SHIFT) & PHYCTRL_CALDONE_MASK; if (caldone != PHYCTRL_CALDONE_DONE) { pr_err("rockchip_emmc_phy_power: caldone timeout.\n");
In function rockchip_emmc_phy_power(), local variable "caldone" could be uninitialized if function regmap_read() returns -EINVAL. However, it will be used directly in the later context, which is potentially unsafe. Signed-off-by: Yizhuo <yzhai003@ucr.edu> --- drivers/phy/rockchip/phy-rockchip-emmc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)