rlimits: switch more rlimit syscalls to do_prlimit

After we added more generic do_prlimit, switch sys_getrlimit to that.
Also switch compat handling, so we can get rid of ugly __user casts
and avoid setting process' address limit to kernel data and back.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

1 files changed, 3 insertions, 14 deletions

diff --git a/kernel/compat.c b/kernel/compat.c
index 5adab05a3172..e167efce8423 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -279,11 +279,6 @@ asmlinkage long compat_sys_setrlimit(unsigned int resource,
                 struct compat_rlimit __user *rlim)
 {
         struct rlimit r;
-        int ret;
-        mm_segment_t old_fs = get_fs ();
-
-        if (resource >= RLIM_NLIMITS)
-                return -EINVAL;
 
         if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
             __get_user(r.rlim_cur, &rlim->rlim_cur) ||
@@ -294,10 +289,7 @@ asmlinkage long compat_sys_setrlimit(unsigned int resource,
                 r.rlim_cur = RLIM_INFINITY;
         if (r.rlim_max == COMPAT_RLIM_INFINITY)
                 r.rlim_max = RLIM_INFINITY;
-        set_fs(KERNEL_DS);
-        ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
-        set_fs(old_fs);
-        return ret;
+        return do_prlimit(current, resource, &r, NULL);
 }
 
 #ifdef COMPAT_RLIM_OLD_INFINITY
@@ -329,16 +321,13 @@ asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
 
 #endif
 
-asmlinkage long compat_sys_getrlimit (unsigned int resource,
+asmlinkage long compat_sys_getrlimit(unsigned int resource,
                 struct compat_rlimit __user *rlim)
 {
         struct rlimit r;
         int ret;
-        mm_segment_t old_fs = get_fs();
 
-        set_fs(KERNEL_DS);
-        ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
-        set_fs(old_fs);
+        ret = do_prlimit(current, resource, NULL, &r);
         if (!ret) {
                 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
                         r.rlim_cur = COMPAT_RLIM_INFINITY;