Commit d3a61f74 authored by Alexander Potapenko's avatar Alexander Potapenko Committed by Linus Torvalds
Browse files

kasan: use error_report_end tracepoint 

Make it possible to trace KASAN error reporting.  A good usecase is
watching for trace events from the userspace to detect and process memory
corruption reports from the kernel.

Link: https://lkml.kernel.org/r/20210121131915.1331302-4-glider@google.com


Signed-off-by: default avatarAlexander Potapenko <glider@google.com>
Suggested-by: default avatarMarco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent f2b84d2e

mm/kasan/report.c

+5 −3
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/module.h>

#include <linux/sched/task_stack.h>

#include <linux/uaccess.h>

#include <trace/events/error_report.h>



#include <asm/sections.h>
@@ -84,8 +85,9 @@ static void start_report(unsigned long *flags) 
	pr_err("==================================================================\n");

}



static void end_report(unsigned long *flags)

static void end_report(unsigned long *flags, unsigned long addr)

{

	trace_error_report_end(ERROR_DETECTOR_KASAN, addr);

	pr_err("==================================================================\n");

	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);

	spin_unlock_irqrestore(&report_lock, *flags);
@@ -355,7 +357,7 @@ void kasan_report_invalid_free(void *object, unsigned long ip) 
	print_address_description(object, tag);

	pr_err("\n");

	print_memory_metadata(object);

	end_report(&flags);

	end_report(&flags, (unsigned long)object);

}



static void __kasan_report(unsigned long addr, size_t size, bool is_write,
@@ -401,7 +403,7 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write, 
		dump_stack();

	}



	end_report(&flags);

	end_report(&flags, addr);

}



bool kasan_report(unsigned long addr, size_t size, bool is_write,