2018-11-27 10:33:52

by Pan Bian

[permalink] [raw]
Subject: [PATCH] NFC: netlink: remove unexpected nfc_put_device

The functions nfc_genl_llc_set_params and nfc_genl_llc_sdreq drops the
reference to dev via nfc_put_device on the error branch that no local
device is found. However, the error handling block reads dev's field and
then put dev again. This may result in use-after-free bugs. The patch
removes the unexpected call to nfc_put_device.

Signed-off-by: Pan Bian <[email protected]>
---
net/nfc/netlink.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 376181c..e1f2057 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -1107,7 +1107,6 @@ static int nfc_genl_llc_set_params(struct sk_buff *skb, struct genl_info *info)

local = nfc_llcp_find_local(dev);
if (!local) {
- nfc_put_device(dev);
rc = -ENODEV;
goto exit;
}
@@ -1167,7 +1166,6 @@ static int nfc_genl_llc_sdreq(struct sk_buff *skb, struct genl_info *info)

local = nfc_llcp_find_local(dev);
if (!local) {
- nfc_put_device(dev);
rc = -ENODEV;
goto exit;
}
--
2.7.4