Re: [syzbot] KMSAN: kernel-infoleak in iowarrior_read

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Subject: KMSAN: kernel-infoleak in iowarrior_read
Author: djahchankoike@xxxxxxxxx

#syz test

iowarrior_callback may send uninitialized data if memcpy fails
copying data from urb to read_queue, check if memcpy is successful
before waking waiting readers.

Signed-off-by: Diogo Jahchan Koike <djahchankoike@xxxxxxxxx>
---
 drivers/usb/misc/iowarrior.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index 6d28467ce352..6f5cd6251d76 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -201,8 +201,9 @@ static void iowarrior_callback(struct urb *urb)
 
 	/* +1 for serial number */
 	offset = intr_idx * (dev->report_size + 1);
-	memcpy(dev->read_queue + offset, urb->transfer_buffer,
-	       dev->report_size);
+	if (!memcpy(dev->read_queue + offset, urb->transfer_buffer,
+	       dev->report_size))
+		goto exit;
 	*(dev->read_queue + offset + (dev->report_size)) = dev->serial_number++;
 
 	atomic_set(&dev->intr_idx, aux_idx);
-- 
2.43.0