Subject: [merged] fork-reorder-permissions-when-violating-number-of-processes-limits.patch removed from -mm tree To: eparis@xxxxxxxxxx,viro@xxxxxxxxxxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Mon, 08 Jul 2013 12:36:05 -0700 The patch titled Subject: fork: reorder permissions when violating number of processes limits has been removed from the -mm tree. Its filename was fork-reorder-permissions-when-violating-number-of-processes-limits.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Eric Paris <eparis@xxxxxxxxxx> Subject: fork: reorder permissions when violating number of processes limits When a task is attempting to violate the RLIMIT_NPROC limit we have a check to see if the task is sufficiently priviledged. The check first looks at CAP_SYS_ADMIN, then CAP_SYS_RESOURCE, then if the task is uid=0. A result is that tasks which are allowed by the uid=0 check are first checked against the security subsystem. This results in the security subsystem auditting a denial for sys_admin and sys_resource and then the task passing the uid=0 check. This patch rearranges the code to first check uid=0, since if we pass that we shouldn't hit the security system at all. We then check sys_resource, since it is the smallest capability which will solve the problem. Lastly we check the fallback everything cap_sysadmin. We don't want to give this capability many places since it is so powerful. This will eliminate many of the false positive/needless denial messages we get when a root task tries to violate the nproc limit. (note that kthreads count against root, so on a sufficiently large machine we can actually get past the default limits before any userspace tasks are launched.) Signed-off-by: Eric Paris <eparis@xxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/fork.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff -puN kernel/fork.c~fork-reorder-permissions-when-violating-number-of-processes-limits kernel/fork.c --- a/kernel/fork.c~fork-reorder-permissions-when-violating-number-of-processes-limits +++ a/kernel/fork.c @@ -1199,8 +1199,8 @@ static struct task_struct *copy_process( retval = -EAGAIN; if (atomic_read(&p->real_cred->user->processes) >= task_rlimit(p, RLIMIT_NPROC)) { - if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) && - p->real_cred->user != INIT_USER) + if (p->real_cred->user != INIT_USER && + !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) goto bad_fork_free; } current->flags &= ~PF_NPROC_EXCEEDED; _ Patches currently in -mm which might be from eparis@xxxxxxxxxx are origin.patch linux-next.patch audit-fix-mq_open-and-mq_unlink-to-add-the-mq-root-as-a-hidden-parent-audit_names-record.patch kernel-auditfilterc-fixing-build-warning.patch kernel-auditfilterc-fix-leak-in-audit_add_rule-error-path.patch audit-fix-decimal-constant-description.patch fanotify-info-leak-in-copy_event_to_user.patch fanotify-fix-races-when-adding-removing-marks.patch fanotify-put-duplicate-code-for-adding-vfsmount-inode-marks-into-an-own-function.patch dnotify-replace-dnotify_mark_mutex-with-mark-mutex-of-dnotify_group.patch inotify-fix-race-when-adding-a-new-watch.patch fsnotify-update-comments-concerning-locking-scheme.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