From: Charlie Sands <sandsch@northvilleschools.net>
To: gregkh@linuxfoundation.org
Cc: Larry.Finger@lwfinger.net, phil@philpotter.co.uk,
linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org,
paskripkin@gmail.com
Subject: [PATCH V2] Fix unsafe memory access by memcmp
Date: Sun, 3 Apr 2022 22:52:07 -0400 [thread overview]
Message-ID: <YkpdVyuQguGzPSNE@sckzor-linux.localdomain> (raw)
This patch fixes sparse warnings about the memcmp function unsafely
accessing userspace memory without first copying it to kernel space.
Signed-off-by: Charlie Sands <sandsch@northvilleschools.net>
---
V2: Fixed checkpatch.pl warning and changed variable name as suggested
by Greg K. H. and improved error checking on the "copy_from_user" function as
suggested by Pavel Skripkin.
drivers/staging/r8188eu/os_dep/ioctl_linux.c | 21 ++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/drivers/staging/r8188eu/os_dep/ioctl_linux.c b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
index 7df213856d66..4b4eec2bde96 100644
--- a/drivers/staging/r8188eu/os_dep/ioctl_linux.c
+++ b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
@@ -3233,23 +3233,28 @@ static int rtw_p2p_get(struct net_device *dev,
struct iw_request_info *info,
union iwreq_data *wrqu, char *extra)
{
- if (!memcmp(wrqu->data.pointer, "status", 6)) {
+ char wrqu_data[9];
+
+ if (copy_from_user(wrqu_data, wrqu->data.pointer, 9) != 0)
+ return 0;
+
+ if (!memcmp(wrqu_data, "status", 6)) {
rtw_p2p_get_status(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "role", 4)) {
+ } else if (!memcmp(wrqu_data, "role", 4)) {
rtw_p2p_get_role(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "peer_ifa", 8)) {
+ } else if (!memcmp(wrqu_data, "peer_ifa", 8)) {
rtw_p2p_get_peer_ifaddr(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "req_cm", 6)) {
+ } else if (!memcmp(wrqu_data, "req_cm", 6)) {
rtw_p2p_get_req_cm(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "peer_deva", 9)) {
+ } else if (!memcmp(wrqu_data, "peer_deva", 9)) {
/* Get the P2P device address when receiving the provision discovery request frame. */
rtw_p2p_get_peer_devaddr(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "group_id", 8)) {
+ } else if (!memcmp(wrqu_data, "group_id", 8)) {
rtw_p2p_get_groupid(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "peer_deva_inv", 9)) {
+ } else if (!memcmp(wrqu_data, "peer_deva_inv", 9)) {
/* Get the P2P device address when receiving the P2P Invitation request frame. */
rtw_p2p_get_peer_devaddr_by_invitation(dev, info, wrqu, extra);
- } else if (!memcmp(wrqu->data.pointer, "op_ch", 5)) {
+ } else if (!memcmp(wrqu_data, "op_ch", 5)) {
rtw_p2p_get_op_ch(dev, info, wrqu, extra);
}
return 0;
--
2.35.1
next reply other threads:[~2022-04-04 2:52 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-04 2:52 Charlie Sands [this message]
2022-04-04 8:02 ` [PATCH V2] Fix unsafe memory access by memcmp Michael Straube
2022-04-04 10:50 ` Dan Carpenter
2022-04-04 11:25 ` Fabio M. De Francesco
2022-04-04 12:03 ` Dan Carpenter
2022-04-04 14:29 ` Fabio M. De Francesco
2022-04-04 14:35 ` Dan Carpenter
2022-04-04 14:47 ` Fabio M. De Francesco
2022-04-04 14:36 ` Greg KH
2022-04-04 16:33 ` Pavel Skripkin
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