forked from mirrors/linux
		
	 e336b40277
			
		
	
	
		e336b40277
		
	
	
	
	
		
			
			Since BUG() and WARN() may use a trap (e.g. UD2 on x86) to get the address where the BUG() has occurred, kprobes can not do single-step out-of-line that instruction. So prohibit probing on such address. Without this fix, if someone put a kprobe on WARN(), the kernel will crash with invalid opcode error instead of outputing warning message, because kernel can not find correct bug address. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S . Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naveen N . Rao <naveen.n.rao@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/156750890133.19112.3393666300746167111.stgit@devnote2 Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
			84 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_BUG_H
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| #define _LINUX_BUG_H
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| 
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| #include <asm/bug.h>
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| #include <linux/compiler.h>
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| #include <linux/build_bug.h>
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| 
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| enum bug_trap_type {
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| 	BUG_TRAP_TYPE_NONE = 0,
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| 	BUG_TRAP_TYPE_WARN = 1,
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| 	BUG_TRAP_TYPE_BUG = 2,
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| };
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| 
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| struct pt_regs;
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| 
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| #ifdef __CHECKER__
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| #define MAYBE_BUILD_BUG_ON(cond) (0)
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| #else /* __CHECKER__ */
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| 
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| #define MAYBE_BUILD_BUG_ON(cond)			\
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| 	do {						\
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| 		if (__builtin_constant_p((cond)))       \
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| 			BUILD_BUG_ON(cond);             \
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| 		else                                    \
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| 			BUG_ON(cond);                   \
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| 	} while (0)
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| 
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| #endif	/* __CHECKER__ */
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| 
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| #ifdef CONFIG_GENERIC_BUG
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| #include <asm-generic/bug.h>
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| 
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| static inline int is_warning_bug(const struct bug_entry *bug)
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| {
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| 	return bug->flags & BUGFLAG_WARNING;
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| }
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| 
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| struct bug_entry *find_bug(unsigned long bugaddr);
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| 
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| enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);
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| 
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| /* These are defined by the architecture */
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| int is_valid_bugaddr(unsigned long addr);
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| 
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| void generic_bug_clear_once(void);
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| 
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| #else	/* !CONFIG_GENERIC_BUG */
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| 
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| static inline void *find_bug(unsigned long bugaddr)
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| {
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| 	return NULL;
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| }
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| 
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| static inline enum bug_trap_type report_bug(unsigned long bug_addr,
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| 					    struct pt_regs *regs)
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| {
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| 	return BUG_TRAP_TYPE_BUG;
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| }
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| 
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| 
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| static inline void generic_bug_clear_once(void) {}
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| 
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| #endif	/* CONFIG_GENERIC_BUG */
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| 
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| /*
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|  * Since detected data corruption should stop operation on the affected
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|  * structures. Return value must be checked and sanely acted on by caller.
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|  */
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| static inline __must_check bool check_data_corruption(bool v) { return v; }
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| #define CHECK_DATA_CORRUPTION(condition, fmt, ...)			 \
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| 	check_data_corruption(({					 \
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| 		bool corruption = unlikely(condition);			 \
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| 		if (corruption) {					 \
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| 			if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
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| 				pr_err(fmt, ##__VA_ARGS__);		 \
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| 				BUG();					 \
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| 			} else						 \
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| 				WARN(1, fmt, ##__VA_ARGS__);		 \
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| 		}							 \
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| 		corruption;						 \
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| 	}))
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| 
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| #endif	/* _LINUX_BUG_H */
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