From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
commit b8ebf250997c5fb253582f42bfe98673801ebebd upstream.
syzbot is reporting uninitialized value at iforce_init_device() [1], for
commit 6ac0aec6b0a6 ("Input: iforce - allow callers supply data buffer
when fetching device IDs") is checking that valid length is shorter than
bytes to read. Since iforce_get_id_packet() stores valid length when
returning 0, the caller needs to check that valid length is longer than or
equals to bytes to read.
Reported-by: syzbot <syzbot+4dd880c1184280378821@xxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Fixes: 6ac0aec6b0a6 ("Input: iforce - allow callers supply data buffer when fetching device IDs")
Link: https://lore.kernel.org/r/531fb432-7396-ad37-ecba-3e42e7f56d5c@xxxxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/input/joystick/iforce/iforce-main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/input/joystick/iforce/iforce-main.c
+++ b/drivers/input/joystick/iforce/iforce-main.c
@@ -273,22 +273,22 @@ int iforce_init_device(struct device *pa
* Get device info.
*/
- if (!iforce_get_id_packet(iforce, 'M', buf, &len) || len < 3)
+ if (!iforce_get_id_packet(iforce, 'M', buf, &len) && len >= 3)
input_dev->id.vendor = get_unaligned_le16(buf + 1);
else
dev_warn(&iforce->dev->dev, "Device does not respond to id packet M\n");
- if (!iforce_get_id_packet(iforce, 'P', buf, &len) || len < 3)
+ if (!iforce_get_id_packet(iforce, 'P', buf, &len) && len >= 3)
input_dev->id.product = get_unaligned_le16(buf + 1);
else
dev_warn(&iforce->dev->dev, "Device does not respond to id packet P\n");
- if (!iforce_get_id_packet(iforce, 'B', buf, &len) || len < 3)
+ if (!iforce_get_id_packet(iforce, 'B', buf, &len) && len >= 3)
iforce->device_memory.end = get_unaligned_le16(buf + 1);
else
dev_warn(&iforce->dev->dev, "Device does not respond to id packet B\n");
- if (!iforce_get_id_packet(iforce, 'N', buf, &len) || len < 2)
+ if (!iforce_get_id_packet(iforce, 'N', buf, &len) && len >= 2)
ff_effects = buf[1];
else
dev_warn(&iforce->dev->dev, "Device does not respond to id packet N\n");
