[PATCH 5.13 143/175] ARM: omap2+: hwmod: fix potential NULL pointer access

From: Greg Kroah-Hartman
Date: Tue Aug 10 2021 - 14:06:15 EST


From: Tero Kristo <t-kristo@xxxxxx>

commit b070f9ca78680486927b799cf6126b128a7c2c1b upstream.

omap_hwmod_get_pwrdm() may access a NULL clk_hw pointer in some failure
cases. Add a check for the case and bail out gracely if this happens.

Reported-by: Dan Murphy <dmurphy@xxxxxx>
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v5.10+
Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-omap2/omap_hwmod.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -3776,6 +3776,7 @@ struct powerdomain *omap_hwmod_get_pwrdm
struct omap_hwmod_ocp_if *oi;
struct clockdomain *clkdm;
struct clk_hw_omap *clk;
+ struct clk_hw *hw;

if (!oh)
return NULL;
@@ -3792,7 +3793,14 @@ struct powerdomain *omap_hwmod_get_pwrdm
c = oi->_clk;
}

- clk = to_clk_hw_omap(__clk_get_hw(c));
+ hw = __clk_get_hw(c);
+ if (!hw)
+ return NULL;
+
+ clk = to_clk_hw_omap(hw);
+ if (!clk)
+ return NULL;
+
clkdm = clk->clkdm;
if (!clkdm)
return NULL;