In panthor_drv.c:panthor_ioctl_group_create(),
the queue count is validated against the hardcoded maximum:
if (!args->queues.count || args->queues.count > MAX_CS_PER_CSG)
return -EINVAL;
However, if the firmware reports fewer slots than MAX_CS_PER_CSG,
panthor_fw_init_ifaces() will only initialize that smaller number of
stream interfaces.
If unprivileged userspace requests more queues than the firmware reported
(but no more than MAX_CS_PER_CSG), cs_slot_prog_locked() fetches an
uninitialized stream interface and may crash when dereferencing
cs_iface->input->ringbuf_base.
Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Cc: [email protected]
Reported-by: [email protected]
Closes:
https://sashiko.dev/#/patchset/[email protected]?part=1
Signed-off-by: Osama Abdelkader <[email protected]>
---
drivers/gpu/drm/panthor/panthor_sched.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c
b/drivers/gpu/drm/panthor/panthor_sched.c
index 5832dccfc093..64749750e6ee 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -3673,6 +3673,9 @@ int panthor_group_create(struct panthor_file *pfile,
hweight64(group_args->tiler_core_mask) <
group_args->max_tiler_cores)
return -EINVAL;
+ if (group_args->queues.count > sched->cs_slot_count)
+ return -EINVAL;
+
group = kzalloc_obj(*group);
if (!group)
return -ENOMEM;
--
2.43.0
