From 4773ef33fc6e59bad2e5d19e334de2fa79c27b74 Mon Sep 17 00:00:00 2001
From: Tobias Klauser <tklauser@distanz.ch>
Date: Fri, 18 Sep 2020 21:20:37 -0700
Subject: [PATCH] stackleak: let stack_erasing_sysctl take a kernel pointer
buffer
Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer. Adjust the
signature of stack_erasing_sysctl to match ctl_table.proc_handler which
fixes the following sparse warning:
kernel/stackleak.c:31:50: warning: incorrect type in argument 3 (different address spaces)
kernel/stackleak.c:31:50: expected void *
kernel/stackleak.c:31:50: got void [noderef] __user *buffer
Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/20200907093253.13656-1-tklauser@distanz.ch
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/stackleak.h | 2 +-
kernel/stackleak.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/stackleak.h b/include/linux/stackleak.h
index 3d5c3271a9a8..a59db2f08e76 100644
--- a/include/linux/stackleak.h
+++ b/include/linux/stackleak.h
@@ -25,7 +25,7 @@ static inline void stackleak_task_init(struct task_struct *t)
#ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
int stack_erasing_sysctl(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp, loff_t *ppos);
+ void *buffer, size_t *lenp, loff_t *ppos);
#endif
#else /* !CONFIG_GCC_PLUGIN_STACKLEAK */
diff --git a/kernel/stackleak.c b/kernel/stackleak.c
index a8fc9ae1d03d..ce161a8e8d97 100644
--- a/kernel/stackleak.c
+++ b/kernel/stackleak.c
@@ -20,7 +20,7 @@
static DEFINE_STATIC_KEY_FALSE(stack_erasing_bypass);
int stack_erasing_sysctl(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp, loff_t *ppos)
+ void *buffer, size_t *lenp, loff_t *ppos)
{
int ret = 0;
int state = !static_branch_unlikely(&stack_erasing_bypass);