[S390] uaccess: implement strict user copy checks

[sfrench/cifs-2.6.git] / arch / s390 / Kconfig.debug

diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug
index 2283933a9a93eef48b2de37aefe944540af03ff4..45e0c6199f36d6484df7adc657527c02c7974a4e 100644 (file)
--- a/arch/s390/Kconfig.debug
+++ b/arch/s390/Kconfig.debug
@@ -6,4 +6,17 @@ config TRACE_IRQFLAGS_SUPPORT
 
 source "lib/Kconfig.debug"
 
+config DEBUG_STRICT_USER_COPY_CHECKS
+       bool "Strict user copy size checks"
+       ---help---
+         Enabling this option turns a certain set of sanity checks for user
+         copy operations into compile time warnings.
+
+         The copy_from_user() etc checks are there to help test if there
+         are sufficient security checks on the length argument of
+         the copy operation, by having gcc prove that the argument is
+         within bounds.
+
+         If unsure, or if you run an older (pre 4.4) gcc, say N.
+
 endmenu