[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1449523512-29200-2-git-send-email-jann@thejh.net>
Date: Mon, 7 Dec 2015 22:25:11 +0100
From: Jann Horn <jann@...jh.net>
To: Andrew Morton <akpm@...ux-foundation.org>,
Kees Cook <keescook@...gle.com>,
Casey Schaufler <casey@...aufler-ca.com>
Cc: Oleg Nesterov <oleg@...hat.com>, Ingo Molnar <mingo@...hat.com>,
James Morris <james.l.morris@...cle.com>,
"Serge E. Hallyn" <serge.hallyn@...ntu.com>,
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
Andy Lutomirski <luto@...nel.org>,
Al Viro <viro@...iv.linux.org.uk>,
"Eric W. Biederman" <ebiederm@...ssion.com>,
Joe Perches <joe@...ches.com>,
Thomas Gleixner <tglx@...utronix.de>,
Michael Kerrisk <mtk.manpages@...il.com>,
linux-kernel@...r.kernel.org, linux-mm@...ck.org,
linux-security-module@...r.kernel.org, linux-api@...r.kernel.org,
security@...nel.org, Willy Tarreau <w@....eu>,
Jann Horn <jann@...jh.net>
Subject: [PATCH 1/2] security: let security modules use PTRACE_MODE_* with bitmasks
It looks like smack and yama weren't aware that the ptrace mode
can have flags ORed into it - PTRACE_MODE_NOAUDIT until now, but
only for /proc/$pid/stat, and with the PTRACE_MODE_*CREDS patch,
all modes have flags ORed into them.
Signed-off-by: Jann Horn <jann@...jh.net>
---
security/smack/smack_lsm.c | 8 +++-----
security/yama/yama_lsm.c | 4 ++--
2 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index ff81026..7c57c7f 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -398,12 +398,10 @@ static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
*/
static inline unsigned int smk_ptrace_mode(unsigned int mode)
{
- switch (mode) {
- case PTRACE_MODE_READ:
- return MAY_READ;
- case PTRACE_MODE_ATTACH:
+ if (mode & PTRACE_MODE_ATTACH)
return MAY_READWRITE;
- }
+ if (mode & PTRACE_MODE_READ)
+ return MAY_READ;
return 0;
}
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index d3c19c9..cb6ed10 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -281,7 +281,7 @@ static int yama_ptrace_access_check(struct task_struct *child,
int rc = 0;
/* require ptrace target be a child of ptracer on attach */
- if (mode == PTRACE_MODE_ATTACH) {
+ if (mode & PTRACE_MODE_ATTACH) {
switch (ptrace_scope) {
case YAMA_SCOPE_DISABLED:
/* No additional restrictions. */
@@ -307,7 +307,7 @@ static int yama_ptrace_access_check(struct task_struct *child,
}
}
- if (rc) {
+ if (rc && (mode & PTRACE_MODE_NOAUDIT) == 0) {
printk_ratelimited(KERN_NOTICE
"ptrace of pid %d was attempted by: %s (pid %d)\n",
child->pid, current->comm, current->pid);
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists