Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Input: avoid calling input_set_abs_val() in the event handling core
input_abs_set_val() can nominally call input_alloc_absinfo() which may
allocate memory with GFP_KERNEL flag. This does not happen when
input_abs_set_val() is called by the input core to set current MT slot when
handling a new input event, but it trips certain static analyzers.
Rearrange the code to access the relevant structures directly.
Reported-by: Teng Qi <starmiku1207184332@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Link: https://lore.kernel.org/r/ZFBg379uuHjf+YEM@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
+4
-2
+4
-2
drivers/input/input.c
+4
-2
drivers/input/input.c
···
190
190
unsigned int code, int *pval)
191
191
{
192
192
struct input_mt *mt = dev->mt;
193
+
bool is_new_slot = false;
193
194
bool is_mt_event;
194
195
int *pold;
195
196
···
211
210
pold = &dev->absinfo[code].value;
212
211
} else if (mt) {
213
212
pold = &mt->slots[mt->slot].abs[code - ABS_MT_FIRST];
213
+
is_new_slot = mt->slot != dev->absinfo[ABS_MT_SLOT].value;
214
214
} else {
215
215
/*
216
216
* Bypass filtering for multi-touch events when
···
230
228
}
231
229
232
230
/* Flush pending "slot" event */
233
-
if (is_mt_event && mt && mt->slot != input_abs_get_val(dev, ABS_MT_SLOT)) {
234
-
input_abs_set_val(dev, ABS_MT_SLOT, mt->slot);
231
+
if (is_new_slot) {
232
+
dev->absinfo[ABS_MT_SLOT].value = mt->slot;
235
233
return INPUT_PASS_TO_HANDLERS | INPUT_SLOT;
236
234
}
237
235