 f322e26238
			
		
	
	
	f322e26238
	
	
	
		
			
			The first is a long standing bug that causes bogus data to show up in the refcnt field of the module_refcnt tracepoint. It was introduced by a merge conflict resolution back in 2.6.35-rc days. The result should be refcnt = incs - decs, but instead it did refcnt = incs + decs. The second fix is to a bug that was introduced in this merge window that allowed for a tracepoint funcs pointer to be used after it was freed. Moving the location of where the probes are released solved the problem. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAABAgAGBQJTa/GQAAoJEKQekfcNnQGuGGUIAJCkrDZdnliE6f6Ur8aXJoX7 gjkXRMmCjLM/X8yQc1H8YwDbSgaTQNmeyQvBbBZ1hUQBaMf5ft4KuFYMGvQRk3jp ZheQVumSzsQfO+yp5dRmzJ6H2G0BCInxq9VZyufZkCPUGsMyiIc+7+SGHEfjMgmW 9XFWyfSr09thVlGanr+OTLXfwFm7GMD9nohLKXh9dhi/tO/gHq6lI83HK42Y1bWG 4fZWJjO5GgCVbW4RanB6yr9RIe8NESKl37JYsAZX61iAvT8/mqIYGWx0i/DEGN5Q ap3WW5QPALLUlvUVgI9Um0KOrotbmKtnRwPeHYDmSQODwuKj5veiLXxL9XdHPLU= =lt0T -----END PGP SIGNATURE----- Merge tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "This contains two fixes. The first is a long standing bug that causes bogus data to show up in the refcnt field of the module_refcnt tracepoint. It was introduced by a merge conflict resolution back in 2.6.35-rc days. The result should be 'refcnt = incs - decs', but instead it did 'refcnt = incs + decs'. The second fix is to a bug that was introduced in this merge window that allowed for a tracepoint funcs pointer to be used after it was freed. Moving the location of where the probes are released solved the problem" * tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracepoint: Fix use of tracepoint funcs after rcu free trace: module: Maintain a valid user count
		
			
				
	
	
		
			133 lines
		
	
	
	
		
			2.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			133 lines
		
	
	
	
		
			2.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Because linux/module.h has tracepoints in the header, and ftrace.h
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|  * used to include this file, define_trace.h includes linux/module.h
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|  * But we do not want the module.h to override the TRACE_SYSTEM macro
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|  * variable that define_trace.h is processing, so we only set it
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|  * when module events are being processed, which would happen when
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|  * CREATE_TRACE_POINTS is defined.
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|  */
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| #ifdef CREATE_TRACE_POINTS
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| #undef TRACE_SYSTEM
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| #define TRACE_SYSTEM module
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| #endif
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| 
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| #if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ)
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| #define _TRACE_MODULE_H
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| 
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| #include <linux/tracepoint.h>
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| 
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| #ifdef CONFIG_MODULES
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| 
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| struct module;
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| 
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| #define show_module_flags(flags) __print_flags(flags, "",	\
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| 	{ (1UL << TAINT_PROPRIETARY_MODULE),	"P" },		\
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| 	{ (1UL << TAINT_OOT_MODULE),		"O" },		\
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| 	{ (1UL << TAINT_FORCED_MODULE),		"F" },		\
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| 	{ (1UL << TAINT_CRAP),			"C" },		\
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| 	{ (1UL << TAINT_UNSIGNED_MODULE),	"E" })
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| 
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| TRACE_EVENT(module_load,
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| 
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| 	TP_PROTO(struct module *mod),
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| 
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| 	TP_ARGS(mod),
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| 
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| 	TP_STRUCT__entry(
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| 		__field(	unsigned int,	taints		)
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| 		__string(	name,		mod->name	)
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| 	),
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| 
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| 	TP_fast_assign(
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| 		__entry->taints = mod->taints;
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| 		__assign_str(name, mod->name);
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| 	),
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| 
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| 	TP_printk("%s %s", __get_str(name), show_module_flags(__entry->taints))
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| );
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| 
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| TRACE_EVENT(module_free,
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| 
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| 	TP_PROTO(struct module *mod),
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| 
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| 	TP_ARGS(mod),
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| 
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| 	TP_STRUCT__entry(
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| 		__string(	name,		mod->name	)
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| 	),
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| 
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| 	TP_fast_assign(
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| 		__assign_str(name, mod->name);
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| 	),
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| 
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| 	TP_printk("%s", __get_str(name))
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| );
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| 
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| #ifdef CONFIG_MODULE_UNLOAD
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| /* trace_module_get/put are only used if CONFIG_MODULE_UNLOAD is defined */
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| 
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| DECLARE_EVENT_CLASS(module_refcnt,
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| 
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| 	TP_PROTO(struct module *mod, unsigned long ip),
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| 
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| 	TP_ARGS(mod, ip),
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| 
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| 	TP_STRUCT__entry(
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| 		__field(	unsigned long,	ip		)
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| 		__field(	int,		refcnt		)
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| 		__string(	name,		mod->name	)
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| 	),
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| 
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| 	TP_fast_assign(
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| 		__entry->ip	= ip;
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| 		__entry->refcnt	= __this_cpu_read(mod->refptr->incs) - __this_cpu_read(mod->refptr->decs);
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| 		__assign_str(name, mod->name);
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| 	),
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| 
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| 	TP_printk("%s call_site=%pf refcnt=%d",
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| 		  __get_str(name), (void *)__entry->ip, __entry->refcnt)
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| );
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| 
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| DEFINE_EVENT(module_refcnt, module_get,
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| 
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| 	TP_PROTO(struct module *mod, unsigned long ip),
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| 
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| 	TP_ARGS(mod, ip)
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| );
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| 
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| DEFINE_EVENT(module_refcnt, module_put,
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| 
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| 	TP_PROTO(struct module *mod, unsigned long ip),
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| 
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| 	TP_ARGS(mod, ip)
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| );
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| #endif /* CONFIG_MODULE_UNLOAD */
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| 
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| TRACE_EVENT(module_request,
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| 
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| 	TP_PROTO(char *name, bool wait, unsigned long ip),
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| 
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| 	TP_ARGS(name, wait, ip),
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| 
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| 	TP_STRUCT__entry(
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| 		__field(	unsigned long,	ip		)
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| 		__field(	bool,		wait		)
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| 		__string(	name,		name		)
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| 	),
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| 
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| 	TP_fast_assign(
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| 		__entry->ip	= ip;
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| 		__entry->wait	= wait;
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| 		__assign_str(name, name);
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| 	),
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| 
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| 	TP_printk("%s wait=%d call_site=%pf",
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| 		  __get_str(name), (int)__entry->wait, (void *)__entry->ip)
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| );
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| 
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| #endif /* CONFIG_MODULES */
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| 
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| #endif /* _TRACE_MODULE_H */
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| 
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| /* This part must be outside protection */
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| #include <trace/define_trace.h>
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