On Fri, Nov 5, 2021 at 9:08 PM Subbaraman Narayanamurthy <quic_subbaram@xxxxxxxxxxx> wrote: > > On 11/5/21 9:37 AM, Rafael J. Wysocki wrote: > > On Fri, Nov 5, 2021 at 5:19 PM Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote: > >> On 05/11/2021 16:14, Rafael J. Wysocki wrote: > >>> On Fri, Nov 5, 2021 at 12:57 AM Subbaraman Narayanamurthy > >>> <quic_subbaram@xxxxxxxxxxx> wrote: > >>>> of_parse_thermal_zones() parses the thermal-zones node and registers a > >>>> thermal_zone device for each subnode. However, if a thermal zone is > >>>> consuming a thermal sensor and that thermal sensor device hasn't probed > >>>> yet, an attempt to set trip_point_*_temp for that thermal zone device > >>>> can cause a NULL pointer dereference. Fix it. > >>>> > >>>> console:/sys/class/thermal/thermal_zone87 # echo 120000 > trip_point_0_temp > >>>> ... > >>>> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 > >>>> ... > >>>> Call trace: > >>>> of_thermal_set_trip_temp+0x40/0xc4 > >>>> trip_point_temp_store+0xc0/0x1dc > >>>> dev_attr_store+0x38/0x88 > >>>> sysfs_kf_write+0x64/0xc0 > >>>> kernfs_fop_write_iter+0x108/0x1d0 > >>>> vfs_write+0x2f4/0x368 > >>>> ksys_write+0x7c/0xec > >>>> __arm64_sys_write+0x20/0x30 > >>>> el0_svc_common.llvm.7279915941325364641+0xbc/0x1bc > >>>> do_el0_svc+0x28/0xa0 > >>>> el0_svc+0x14/0x24 > >>>> el0_sync_handler+0x88/0xec > >>>> el0_sync+0x1c0/0x200 > >>>> > >>>> While at it, fix the possible NULL pointer dereference in other > >>>> functions as well: of_thermal_get_temp(), of_thermal_set_emul_temp(), > >>>> of_thermal_get_trend(). > >>> Can the subject be more specific, please? > >>> > >>> The issue appears to be limited to the of_thermal_ family of > >>> functions, but the subject doesn't reflect that at all. > >>> > >>>> Suggested-by: David Collins <quic_collinsd@xxxxxxxxxxx> > >>>> Signed-off-by: Subbaraman Narayanamurthy <quic_subbaram@xxxxxxxxxxx> > >>> Daniel, any concerns regarding the code changes below? > >> I've a concern about the root cause but I did not have time to > >> investigate how to fix it nicely. > >> > >> thermal_of is responsible of introducing itself between the thermal core > >> code and the backend. So it defines the ops which in turn call the > >> sensor ops leading us to this problem. > >> > >> So, without a better solution, this fix can be applied until we rethink > >> the thermal_of approach. > >> > >> Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> > > Thanks! > > > > I've queued it up for 5.16-rc as "thermal: Fix NULL pointer > > dereferences in of_thermal_ functions". > > Thanks, Daniel and Rafael. So, I guess I don't need to send v3 with fixing commit subject right? Right.
