This is a note to let you know that I've just added the patch titled security: let security modules use PTRACE_MODE_* with bitmasks to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: security-let-security-modules-use-ptrace_mode_-with-bitmasks.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3dfb7d8cdbc7ea0c2970450e60818bb3eefbad69 Mon Sep 17 00:00:00 2001 From: Jann Horn <jann@xxxxxxxxx> Date: Wed, 20 Jan 2016 15:00:01 -0800 Subject: security: let security modules use PTRACE_MODE_* with bitmasks From: Jann Horn <jann@xxxxxxxxx> commit 3dfb7d8cdbc7ea0c2970450e60818bb3eefbad69 upstream. 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@xxxxxxxxx> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> Acked-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: James Morris <james.l.morris@xxxxxxxxxx> Cc: "Serge E. Hallyn" <serge.hallyn@xxxxxxxxxx> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Cc: Willy Tarreau <w@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- security/smack/smack_lsm.c | 8 +++----- security/yama/yama_lsm.c | 4 ++-- 2 files changed, 5 insertions(+), 7 deletions(-) --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -398,12 +398,10 @@ static int smk_copy_relabel(struct list_ */ 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; } --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -281,7 +281,7 @@ static int yama_ptrace_access_check(stru 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(stru } } - 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); Patches currently in stable-queue which might be from jann@xxxxxxxxx are queue-4.4/seccomp-always-propagate-no_new_privs-on-tsync.patch queue-4.4/security-let-security-modules-use-ptrace_mode_-with-bitmasks.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html