Messages in this thread | | | Date | Fri, 4 Feb 2011 16:05:13 +0000 | From | "Serge E. Hallyn" <> | Subject | Re: CAP_SYSLOG, 2.6.38 and user space |
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Quoting Serge E. Hallyn (serge@hallyn.com): > >From 2d7408541dd3a6e19a4265b028233789be6a40f4 Mon Sep 17 00:00:00 2001 > From: Serge Hallyn <serge@peq.(none)> > Date: Thu, 3 Feb 2011 09:26:15 -0600 > Subject: [PATCH 1/1] cap_syslog: don't refuse cap_sys_admin for now > > At 2.6.39 or 2.6.40, let's add a sysctl which defaults to 0. When > 0, refuse if cap_sys_admin, if 1, then allow. This will allow > users to acknowledge (permanently, if they must, using /etc/sysctl.conf) > that they've seen the syslog message about cap_sys_admin being > deprecated for syslog. > > Signed-off-by: Serge Hallyn <serge@hallyn.com> > --- > kernel/printk.c | 26 ++++++++++++++++---------- > 1 files changed, 16 insertions(+), 10 deletions(-) > > diff --git a/kernel/printk.c b/kernel/printk.c > index 2ddbdc7..bc56386 100644 > --- a/kernel/printk.c > +++ b/kernel/printk.c > @@ -274,12 +274,24 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) > * at open time. > */ > if (type == SYSLOG_ACTION_OPEN || !from_file) { > - if (dmesg_restrict && !capable(CAP_SYSLOG)) > - goto warn; /* switch to return -EPERM after 2.6.39 */ > + if (dmesg_restrict && !capable(CAP_SYSLOG)) { > + /* remove after 2.6.39 */ > + if (capable(CAP_SYS_ADMIN)) > + WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN " > + "but no CAP_SYSLOG (deprecated).\n"); > + else > + return -EPERM; > + } > if ((type != SYSLOG_ACTION_READ_ALL && > type != SYSLOG_ACTION_SIZE_BUFFER) && > - !capable(CAP_SYSLOG)) > - goto warn; /* switch to return -EPERM after 2.6.39 */ > + !capable(CAP_SYSLOG)) { > + /* remove after 2.6.39 */ > + if (capable(CAP_SYS_ADMIN)) > + WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN " > + "but no CAP_SYSLOG (deprecated).\n"); > + else > + return -EPERM; > + } > } > > error = security_syslog(type); > @@ -423,12 +435,6 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) > } > out: > return error; > -warn: > - /* remove after 2.6.39 */ > - if (capable(CAP_SYS_ADMIN)) > - WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN " > - "but no CAP_SYSLOG (deprecated and denied).\n"); > - return -EPERM; > } > > SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len) > -- > 1.7.2.3 >
James, do you mind taking this patch?
thanks, -serge
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