Commit 4773ef33 authored Sep 18, 2020 by Tobias Klauser Committed by Linus Torvalds Sep 19, 2020

stackleak: let stack_erasing_sysctl take a kernel pointer buffer



Commit 32927393 ("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: 32927393 ("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>

parent 7bb82ac3

include/linux/stackleak.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -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 */

kernel/stackleak.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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);

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