Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 209 insertions, 0 deletions

diff --git a/kernel/exec_domain.c b/kernel/exec_domain.c
new file mode 100644
index 000000000000..867d6dbeb574
--- /dev/null
+++ b/kernel/exec_domain.c
@@ -0,0 +1,209 @@
+/*
+ * Handling of different ABIs (personalities).
+ *
+ * We group personalities into execution domains which have their
+ * own handlers for kernel entry points, signal mapping, etc...
+ *
+ * 2001-05-06	Complete rewrite,  Christoph Hellwig (hch@infradead.org)
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/personality.h>
+#include <linux/sched.h>
+#include <linux/syscalls.h>
+#include <linux/sysctl.h>
+#include <linux/types.h>
+
+
+static void default_handler(int, struct pt_regs *);
+
+static struct exec_domain *exec_domains = &default_exec_domain;
+static DEFINE_RWLOCK(exec_domains_lock);
+
+
+static u_long ident_map[32] = {
+	0,	1,	2,	3,	4,	5,	6,	7,
+	8,	9,	10,	11,	12,	13,	14,	15,
+	16,	17,	18,	19,	20,	21,	22,	23,
+	24,	25,	26,	27,	28,	29,	30,	31
+};
+
+struct exec_domain default_exec_domain = {
+	.name		= "Linux",		/* name */
+	.handler	= default_handler,	/* lcall7 causes a seg fault. */
+	.pers_low	= 0, 			/* PER_LINUX personality. */
+	.pers_high	= 0,			/* PER_LINUX personality. */
+	.signal_map	= ident_map,		/* Identity map signals. */
+	.signal_invmap	= ident_map,		/*  - both ways. */
+};
+
+
+static void
+default_handler(int segment, struct pt_regs *regp)
+{
+	set_personality(0);
+
+	if (current_thread_info()->exec_domain->handler != default_handler)
+		current_thread_info()->exec_domain->handler(segment, regp);
+	else
+		send_sig(SIGSEGV, current, 1);
+}
+
+static struct exec_domain *
+lookup_exec_domain(u_long personality)
+{
+	struct exec_domain *	ep;
+	u_long			pers = personality(personality);
+		
+	read_lock(&exec_domains_lock);
+	for (ep = exec_domains; ep; ep = ep->next) {
+		if (pers >= ep->pers_low && pers <= ep->pers_high)
+			if (try_module_get(ep->module))
+				goto out;
+	}
+
+#ifdef CONFIG_KMOD
+	read_unlock(&exec_domains_lock);
+	request_module("personality-%ld", pers);
+	read_lock(&exec_domains_lock);
+
+	for (ep = exec_domains; ep; ep = ep->next) {
+		if (pers >= ep->pers_low && pers <= ep->pers_high)
+			if (try_module_get(ep->module))
+				goto out;
+	}
+#endif
+
+	ep = &default_exec_domain;
+out:
+	read_unlock(&exec_domains_lock);
+	return (ep);
+}
+
+int
+register_exec_domain(struct exec_domain *ep)
+{
+	struct exec_domain	*tmp;
+	int			err = -EBUSY;
+
+	if (ep == NULL)
+		return -EINVAL;
+
+	if (ep->next != NULL)
+		return -EBUSY;
+
+	write_lock(&exec_domains_lock);
+	for (tmp = exec_domains; tmp; tmp = tmp->next) {
+		if (tmp == ep)
+			goto out;
+	}
+
+	ep->next = exec_domains;
+	exec_domains = ep;
+	err = 0;
+
+out:
+	write_unlock(&exec_domains_lock);
+	return (err);
+}
+
+int
+unregister_exec_domain(struct exec_domain *ep)
+{
+	struct exec_domain	**epp;
+
+	epp = &exec_domains;
+	write_lock(&exec_domains_lock);
+	for (epp = &exec_domains; *epp; epp = &(*epp)->next) {
+		if (ep == *epp)
+			goto unregister;
+	}
+	write_unlock(&exec_domains_lock);
+	return -EINVAL;
+
+unregister:
+	*epp = ep->next;
+	ep->next = NULL;
+	write_unlock(&exec_domains_lock);
+	return 0;
+}
+
+int
+__set_personality(u_long personality)
+{
+	struct exec_domain	*ep, *oep;
+
+	ep = lookup_exec_domain(personality);
+	if (ep == current_thread_info()->exec_domain) {
+		current->personality = personality;
+		return 0;
+	}
+
+	if (atomic_read(&current->fs->count) != 1) {
+		struct fs_struct *fsp, *ofsp;
+
+		fsp = copy_fs_struct(current->fs);
+		if (fsp == NULL) {
+			module_put(ep->module);
+			return -ENOMEM;
+		}
+
+		task_lock(current);
+		ofsp = current->fs;
+		current->fs = fsp;
+		task_unlock(current);
+
+		put_fs_struct(ofsp);
+	}
+
+	/*
+	 * At that point we are guaranteed to be the sole owner of
+	 * current->fs.
+	 */
+
+	current->personality = personality;
+	oep = current_thread_info()->exec_domain;
+	current_thread_info()->exec_domain = ep;
+	set_fs_altroot();
+
+	module_put(oep->module);
+	return 0;
+}
+
+int
+get_exec_domain_list(char *page)
+{
+	struct exec_domain	*ep;
+	int			len = 0;
+
+	read_lock(&exec_domains_lock);
+	for (ep = exec_domains; ep && len < PAGE_SIZE - 80; ep = ep->next)
+		len += sprintf(page + len, "%d-%d\t%-16s\t[%s]\n",
+			       ep->pers_low, ep->pers_high, ep->name,
+			       module_name(ep->module));
+	read_unlock(&exec_domains_lock);
+	return (len);
+}
+
+asmlinkage long
+sys_personality(u_long personality)
+{
+	u_long old = current->personality;
+
+	if (personality != 0xffffffff) {
+		set_personality(personality);
+		if (current->personality != personality)
+			return -EINVAL;
+	}
+
+	return (long)old;
+}
+
+
+EXPORT_SYMBOL(register_exec_domain);
+EXPORT_SYMBOL(unregister_exec_domain);
+EXPORT_SYMBOL(__set_personality);