| Message ID | 20211012101521.32087-1-srinivas.kandagatla@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | soundwire: bus: stop dereferencing invalid slave pointer | expand |
On 10/12/21 5:15 AM, Srinivas Kandagatla wrote: > Slave pointer is invalid after end of list iteration, using this > would result in below Memory abort. > > Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 > ... > Call trace: > __dev_printk+0x34/0x7c > _dev_warn+0x6c/0x90 > sdw_bus_exit_clk_stop+0x194/0x1d0 > swrm_runtime_resume+0x13c/0x238 > pm_generic_runtime_resume+0x2c/0x48 > __rpm_callback+0x44/0x150 > rpm_callback+0x6c/0x78 > rpm_resume+0x314/0x558 > rpm_resume+0x378/0x558 > rpm_resume+0x378/0x558 > __pm_runtime_resume+0x3c/0x88 > > Use bus->dev instead to print this error message. > > Fixes: b50bb8ba369cd ("soundwire: bus: handle -ENODATA errors in clock stop/start sequences") > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Nice catch, even if the 'slave' pointer was valid it makes no sense to use this device for a bus-level operation. Using the bus->dev is the right thing to do. Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > --- > drivers/soundwire/bus.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c > index 1b115734a8f6..67369e941d0d 100644 > --- a/drivers/soundwire/bus.c > +++ b/drivers/soundwire/bus.c > @@ -1110,7 +1110,7 @@ int sdw_bus_exit_clk_stop(struct sdw_bus *bus) > if (!simple_clk_stop) { > ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM); > if (ret < 0) > - dev_warn(&slave->dev, "clock stop deprepare wait failed:%d\n", ret); > + dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret); > } > > list_for_each_entry(slave, &bus->slaves, node) { >
On 12-10-21, 11:15, Srinivas Kandagatla wrote: > Slave pointer is invalid after end of list iteration, using this > would result in below Memory abort. Applied, thanks
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 1b115734a8f6..67369e941d0d 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -1110,7 +1110,7 @@ int sdw_bus_exit_clk_stop(struct sdw_bus *bus) if (!simple_clk_stop) { ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM); if (ret < 0) - dev_warn(&slave->dev, "clock stop deprepare wait failed:%d\n", ret); + dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret); } list_for_each_entry(slave, &bus->slaves, node) {
Slave pointer is invalid after end of list iteration, using this would result in below Memory abort. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 ... Call trace: __dev_printk+0x34/0x7c _dev_warn+0x6c/0x90 sdw_bus_exit_clk_stop+0x194/0x1d0 swrm_runtime_resume+0x13c/0x238 pm_generic_runtime_resume+0x2c/0x48 __rpm_callback+0x44/0x150 rpm_callback+0x6c/0x78 rpm_resume+0x314/0x558 rpm_resume+0x378/0x558 rpm_resume+0x378/0x558 __pm_runtime_resume+0x3c/0x88 Use bus->dev instead to print this error message. Fixes: b50bb8ba369cd ("soundwire: bus: handle -ENODATA errors in clock stop/start sequences") Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> --- drivers/soundwire/bus.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)