UBUNTU: Ubuntu-snapdragon-4.4.0-1077.82

[mirror_ubuntu-artful-kernel.git] / kernel / sys.c

diff --git a/kernel/sys.c b/kernel/sys.c
index 6af9212ab5aab7cef491eb4e40e7c9277c1f2ac0..fae5773643f902024df3918323818105e39356f9 100644 (file)
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1098,6 +1098,21 @@ out:
 
 DECLARE_RWSEM(uts_sem);
 
+#ifdef COMPAT_UTS_MACHINE
+static char compat_uts_machine[__OLD_UTS_LEN+1] = COMPAT_UTS_MACHINE;
+
+static int __init parse_compat_uts_machine(char *arg)
+{
+       strncpy(compat_uts_machine, arg, __OLD_UTS_LEN);
+       compat_uts_machine[__OLD_UTS_LEN] = 0;
+       return 0;
+}
+early_param("compat_uts_machine", parse_compat_uts_machine);
+
+#undef COMPAT_UTS_MACHINE
+#define COMPAT_UTS_MACHINE compat_uts_machine
+#endif
+
 #ifdef COMPAT_UTS_MACHINE
 #define override_architecture(name) \
        (personality(current->personality) == PER_LINUX32 && \
@@ -1853,11 +1868,13 @@ static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data
                user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
        }
 
-       if (prctl_map.exe_fd != (u32)-1)
+       if (prctl_map.exe_fd != (u32)-1) {
                error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
-       down_read(&mm->mmap_sem);
-       if (error)
-               goto out;
+               if (error)
+                       return error;
+       }
+
+       down_write(&mm->mmap_sem);
 
        /*
         * We don't validate if these members are pointing to
@@ -1894,10 +1911,8 @@ static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data
        if (prctl_map.auxv_size)
                memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
 
-       error = 0;
-out:
-       up_read(&mm->mmap_sem);
-       return error;
+       up_write(&mm->mmap_sem);
+       return 0;
 }
 #endif /* CONFIG_CHECKPOINT_RESTORE */
 
@@ -1963,7 +1978,7 @@ static int prctl_set_mm(int opt, unsigned long addr,
 
        error = -EINVAL;
 
-       down_read(&mm->mmap_sem);
+       down_write(&mm->mmap_sem);
        vma = find_vma(mm, addr);
 
        prctl_map.start_code    = mm->start_code;
@@ -2056,7 +2071,7 @@ static int prctl_set_mm(int opt, unsigned long addr,
 
        error = 0;
 out:
-       up_read(&mm->mmap_sem);
+       up_write(&mm->mmap_sem);
        return error;
 }