From: Teng Qi <starmiku1207184332@xxxxxxxxx>
input_alloc_absinfo() may cause the kernel to sleep by calling kcalloc() with
the GFP_KERNEL flag. It may be called by input_event() holding spinlock through
the following call path:
input_event(), 433
input_handle_event(), 399
input_get_disposition(), 294
input_handle_abs_event(), 232
input_abs_set_val(), Clang suggests it calls input_alloc_absinfo()
unconditionally
input_alloc_absinfo(), 483
kcalloc(..., GFP_KERNEL)
This call path can potentially trigger a sleep-in-atomic bug. To prevent this
potential bug, we modify input_alloc_absinfo() to use the GFP_ATOMIC flag
instead of the GFP_KERNEL flag.
The possible bug is detected by a static code analysis tool.
Signed-off-by: Teng Qi <starmiku1207184332@xxxxxxxxx>
---
drivers/input/input.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 37e876d45eb9..eefc4c85a693 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -480,7 +480,7 @@ void input_alloc_absinfo(struct input_dev *dev)
if (dev->absinfo)
return;
- dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_KERNEL);
+ dev->absinfo = kcalloc(ABS_CNT, sizeof(*dev->absinfo), GFP_ATOMIC);
if (!dev->absinfo) {
dev_err(dev->dev.parent ?: &dev->dev,
"%s: unable to allocate memory\n", __func__);
--
2.25.1
