4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jeremy Cline jeremy@jcline.org
[ Upstream commit 354a6e707e29cb0c007176ee5b8db8be7bd2dee0 ]
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 jeremy@jcline.org Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/20231009200054.82557-1-jeremy@jcline.org Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 66608e6c5b0ec..33723d843e472 100644 --- a/net/nfc/nci/core.c +++ b/net/nfc/nci/core.c @@ -906,6 +906,11 @@ 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);