From 7bb82ac30c3dd4ecf1485685cbe84d2ba10dddf4 Mon Sep 17 00:00:00 2001
From: Tobias Klauser <tklauser@distanz.ch>
Date: Fri, 18 Sep 2020 21:20:34 -0700
Subject: [PATCH] ftrace: let ftrace_enable_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 ftrace_enable_sysctl to match ctl_table.proc_handler which
fixes the following sparse warning:

kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces)
kernel/trace/ftrace.c:7544:43:    expected void *
kernel/trace/ftrace.c:7544:43:    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/20200907093207.13540-1-tklauser@distanz.ch
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 include/linux/ftrace.h | 3 +--
 kernel/trace/ftrace.c  | 3 +--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index ce2c06f72e863f..e5c2d5cc6e6ad7 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -85,8 +85,7 @@ static inline int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *val
 extern int ftrace_enabled;
 extern int
 ftrace_enable_sysctl(struct ctl_table *table, int write,
-		     void __user *buffer, size_t *lenp,
-		     loff_t *ppos);
+		     void *buffer, size_t *lenp, loff_t *ppos);
 
 struct ftrace_ops;
 
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 275441254bb57b..e9fa580f3083a1 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -7531,8 +7531,7 @@ static bool is_permanent_ops_registered(void)
 
 int
 ftrace_enable_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 = -ENODEV;
 
-- 
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