Re: [PATCH 1/3] drm/msm: Avoid NULL dereference in msm_disp_state_print_regs()

From: Abhinav Kumar
Date: Mon Oct 14 2024 - 14:53:22 EST




On 10/14/2024 9:36 AM, Douglas Anderson wrote:
If the allocation in msm_disp_state_dump_regs() failed then
`block->state` can be NULL. The msm_disp_state_print_regs() function
_does_ have code to try to handle it with:

if (*reg)
dump_addr = *reg;

...but since "dump_addr" is initialized to NULL the above is actually
a noop. The code then goes on to dereference `dump_addr`.

Make the function print "Registers not stored" when it sees a NULL to
solve this. Since we're touching the code, fix
msm_disp_state_print_regs() not to pointlessly take a double-pointer
and properly mark the pointer as `const`.

Fixes: 98659487b845 ("drm/msm: add support to take dpu snapshot")
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---

drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)


LGTM, thanks for the fix

Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>