kernel_optimize_test/include/linux/bug.h
Masami Hiramatsu e336b40277 kprobes: Prohibit probing on BUG() and WARN() address
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>
2019-09-05 10:15:16 +02:00

85 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_BUG_H
#define _LINUX_BUG_H
#include <asm/bug.h>
#include <linux/compiler.h>
#include <linux/build_bug.h>
enum bug_trap_type {
BUG_TRAP_TYPE_NONE = 0,
BUG_TRAP_TYPE_WARN = 1,
BUG_TRAP_TYPE_BUG = 2,
};
struct pt_regs;
#ifdef __CHECKER__
#define MAYBE_BUILD_BUG_ON(cond) (0)
#else /* __CHECKER__ */
#define MAYBE_BUILD_BUG_ON(cond) \
do { \
if (__builtin_constant_p((cond))) \
BUILD_BUG_ON(cond); \
else \
BUG_ON(cond); \
} while (0)
#endif /* __CHECKER__ */
#ifdef CONFIG_GENERIC_BUG
#include <asm-generic/bug.h>
static inline int is_warning_bug(const struct bug_entry *bug)
{
return bug->flags & BUGFLAG_WARNING;
}
struct bug_entry *find_bug(unsigned long bugaddr);
enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);
/* These are defined by the architecture */
int is_valid_bugaddr(unsigned long addr);
void generic_bug_clear_once(void);
#else /* !CONFIG_GENERIC_BUG */
static inline void *find_bug(unsigned long bugaddr)
{
return NULL;
}
static inline enum bug_trap_type report_bug(unsigned long bug_addr,
struct pt_regs *regs)
{
return BUG_TRAP_TYPE_BUG;
}
static inline void generic_bug_clear_once(void) {}
#endif /* CONFIG_GENERIC_BUG */
/*
* Since detected data corruption should stop operation on the affected
* structures. Return value must be checked and sanely acted on by caller.
*/
static inline __must_check bool check_data_corruption(bool v) { return v; }
#define CHECK_DATA_CORRUPTION(condition, fmt, ...) \
check_data_corruption(({ \
bool corruption = unlikely(condition); \
if (corruption) { \
if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
pr_err(fmt, ##__VA_ARGS__); \
BUG(); \
} else \
WARN(1, fmt, ##__VA_ARGS__); \
} \
corruption; \
}))
#endif /* _LINUX_BUG_H */