On 10/31/21 20:40, syzbot wrote:
Hello,
syzbot found the following issue on:
HEAD commit: 119c85055d86 Merge tag 'powerpc-5.15-6' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1453e1f4b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=6362530af157355b
dashboard link: https://syzkaller.appspot.com/bug?extid=e3fcb9c4f3c2a931dc40
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1128465cb00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1431dfe2b00000
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10f27096b00000
final oops: https://syzkaller.appspot.com/x/report.txt?x=12f27096b00000
console output: https://syzkaller.appspot.com/x/log.txt?x=14f27096b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e3fcb9c4f3c2a931dc40@xxxxxxxxxxxxxxxxxxxxxxxxx
Bluetooth: hci0: unknown advertising packet type: 0x90
Bluetooth: hci0: Dropping invalid advertising data
If packet has invalid length we should check if we won't go beyond
skb->tail on next iteration.
#syz test
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
With regards,
Pavel Skripkin
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 0bca035bf2dc..3e294584aa7c 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -5790,6 +5790,11 @@ static void hci_le_adv_report_evt(struct hci_dev *hdev, struct sk_buff *skb)
}
ptr += sizeof(*ev) + ev->length + 1;
+
+ if (ptr >= (void *) skb_tail_pointer(skb)) {
+ bt_dev_err(hdev, "Malicious advertising data. Stopping processing");
+ break;
+ }
}
hci_dev_unlock(hdev);
