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authorHeiko Carstens <hca@linux.ibm.com>2023-04-05 15:08:40 +0200
committerVasily Gorbik <gor@linux.ibm.com>2023-04-20 11:36:35 +0200
commit491a78663e039fabc58c892ca8f2c2e08caaf4f8 (patch)
tree2c4ae50cfbe10e680a68e7fc1b19985af60dffa0 /kernel
parents390: select ARCH_USE_SYM_ANNOTATIONS (diff)
downloadlinux-491a78663e039fabc58c892ca8f2c2e08caaf4f8.tar.xz
linux-491a78663e039fabc58c892ca8f2c2e08caaf4f8.zip
stackleak: allow to specify arch specific stackleak poison function
Factor out the code that fills the stack with the stackleak poison value in order to allow architectures to provide a faster implementation. Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20230405130841.1350565-2-hca@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/stackleak.c17
1 files changed, 13 insertions, 4 deletions
diff --git a/kernel/stackleak.c b/kernel/stackleak.c
index c2c33d2202e9..34c9d81eea94 100644
--- a/kernel/stackleak.c
+++ b/kernel/stackleak.c
@@ -70,6 +70,18 @@ late_initcall(stackleak_sysctls_init);
#define skip_erasing() false
#endif /* CONFIG_STACKLEAK_RUNTIME_DISABLE */
+#ifndef __stackleak_poison
+static __always_inline void __stackleak_poison(unsigned long erase_low,
+ unsigned long erase_high,
+ unsigned long poison)
+{
+ while (erase_low < erase_high) {
+ *(unsigned long *)erase_low = poison;
+ erase_low += sizeof(unsigned long);
+ }
+}
+#endif
+
static __always_inline void __stackleak_erase(bool on_task_stack)
{
const unsigned long task_stack_low = stackleak_task_low_bound(current);
@@ -101,10 +113,7 @@ static __always_inline void __stackleak_erase(bool on_task_stack)
else
erase_high = task_stack_high;
- while (erase_low < erase_high) {
- *(unsigned long *)erase_low = STACKLEAK_POISON;
- erase_low += sizeof(unsigned long);
- }
+ __stackleak_poison(erase_low, erase_high, STACKLEAK_POISON);
/* Reset the 'lowest_stack' value for the next syscall */
current->lowest_stack = task_stack_high;