The patch titled userns: allow killing tasks in your own or child userns has been removed from the -mm tree. Its filename was userns-allow-killing-tasks-in-your-own-or-child-userns.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: userns: allow killing tasks in your own or child userns From: "Serge E. Hallyn" <serge@xxxxxxxxxx> Changelog: Dec 8: Fixed bug in my check_kill_permission pointed out by Eric Biederman. Dec 13: Apply Eric's suggestion to pass target task into kill_ok_by_cred() for clarity Dec 31: address comment by Eric Biederman: don't need cred/tcred in check_kill_permission. Jan 1: use const cred struct. Jan 11: Per Bastian Blank's advice, clean up kill_ok_by_cred(). Feb 16: kill_ok_by_cred: fix bad parentheses Feb 23: per akpm, let compiler inline kill_ok_by_cred Signed-off-by: Serge E. Hallyn <serge.hallyn@xxxxxxxxxxxxx> Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxx> Acked-by: David Howells <dhowells@xxxxxxxxxx> Cc: James Morris <jmorris@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/signal.c | 30 ++++++++++++++++++++++-------- 1 file changed, 22 insertions(+), 8 deletions(-) diff -puN kernel/signal.c~userns-allow-killing-tasks-in-your-own-or-child-userns kernel/signal.c --- a/kernel/signal.c~userns-allow-killing-tasks-in-your-own-or-child-userns +++ a/kernel/signal.c @@ -636,13 +636,33 @@ static inline bool si_fromuser(const str } /* + * called with RCU read lock from check_kill_permission() + */ +static int kill_ok_by_cred(struct task_struct *t) +{ + const struct cred *cred = current_cred(); + const struct cred *tcred = __task_cred(t); + + if (cred->user->user_ns == tcred->user->user_ns && + (cred->euid == tcred->suid || + cred->euid == tcred->uid || + cred->uid == tcred->suid || + cred->uid == tcred->uid)) + return 1; + + if (ns_capable(tcred->user->user_ns, CAP_KILL)) + return 1; + + return 0; +} + +/* * Bad permissions for sending the signal * - the caller must hold the RCU read lock */ static int check_kill_permission(int sig, struct siginfo *info, struct task_struct *t) { - const struct cred *cred, *tcred; struct pid *sid; int error; @@ -656,14 +676,8 @@ static int check_kill_permission(int sig if (error) return error; - cred = current_cred(); - tcred = __task_cred(t); if (!same_thread_group(current, t) && - (cred->euid ^ tcred->suid) && - (cred->euid ^ tcred->uid) && - (cred->uid ^ tcred->suid) && - (cred->uid ^ tcred->uid) && - !capable(CAP_KILL)) { + !kill_ok_by_cred(t)) { switch (sig) { case SIGCONT: sid = task_session(t); _ Patches currently in -mm which might be from serge@xxxxxxxxxx are origin.patch lib-hexdumpc-make-hex2bin-return-the-updated-src-address.patch fs-binfmt_miscc-use-kernels-hex_to_bin-method.patch fs-binfmt_miscc-use-kernels-hex_to_bin-method-fix.patch fs-binfmt_miscc-use-kernels-hex_to_bin-method-fix-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html