Re: [PATCH -resend 1/6] mISDN: Add support for group membership check

From: Sergei Shtylyov
Date: Wed May 22 2013 - 15:04:21 EST


On 22-05-2013 16:59, Jiri Slaby wrote:

From: Jeff Mahoney <jeffm@xxxxxxxx>

This patch adds a module parameter to allow a group access to the
mISDN devices. Otherwise, unpriviledged users on systems with ISDN
hardware have the ability to dial out, potentially causing expensive

Based on a different implementation by Patrick Koppen <isdn4linux@xxxxxxxxx>

Acked-by: Jeff Mahoney <jeffm@xxxxxxxx>
Cc: Patrick Koppen <isdn4linux@xxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Cc: Karsten Keil <isdn@xxxxxxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
drivers/isdn/mISDN/core.c | 3 +++
drivers/isdn/mISDN/core.h | 1 +
drivers/isdn/mISDN/socket.c | 8 ++++++++
3 files changed, 12 insertions(+)

diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
index e47dcb9..71f4986 100644
--- a/drivers/isdn/mISDN/socket.c
+++ b/drivers/isdn/mISDN/socket.c
@@ -612,6 +612,10 @@ data_sock_create(struct net *net, struct socket *sock, int protocol)
struct sock *sk;

+ if(!capable(CAP_SYS_ADMIN) && (misdn_permitted_gid != current_gid())

Did you run this thru scripts/ There should be space after *if*. Also, () around != are not neccessary...

@@ -694,6 +698,10 @@ base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
struct mISDN_devrename dn;
+ if(!capable(CAP_SYS_ADMIN)

Again, need space after *if*.

+ && (misdn_permitted_gid != current_gid())

Better leave && on a previous line and align the line under !. () again are not necessary.

+ && (!in_group_p(misdn_permitted_gid)))

() around !x are simply not needed -- ! operator has very high priority.

WBR, Sergei

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