From 354a6e707e29cb0c007176ee5b8db8be7bd2dee0 Mon Sep 17 00:00:00 2001 From: Jeremy Cline Date: Mon, 9 Oct 2023 16:00:54 -0400 Subject: [PATCH] nfc: nci: assert requested protocol is valid The protocol is used in a bit mask to determine if the protocol is supported. Assert the provided protocol is less than the maximum defined so it doesn't potentially perform a shift-out-of-bounds and provide a clearer error for undefined protocols vs unsupported ones. Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation") Reported-and-tested-by: syzbot+0839b78e119aae1fec78@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0839b78e119aae1fec78 Signed-off-by: Jeremy Cline Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20231009200054.82557-1-jeremy@jcline.org Signed-off-by: Paolo Abeni --- net/nfc/nci/core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c index fff755d..6c9592d 100644 --- a/net/nfc/nci/core.c +++ b/net/nfc/nci/core.c @@ -909,6 +909,11 @@ static int nci_activate_target(struct nfc_dev *nfc_dev, return -EINVAL; } + if (protocol >= NFC_PROTO_MAX) { + pr_err("the requested nfc protocol is invalid\n"); + return -EINVAL; + } + if (!(nci_target->supported_protocols & (1 << protocol))) { pr_err("target does not support the requested protocol 0x%x\n", protocol); -- 2.7.4