There is a potential security issue that perf kernel samples may be leaked even though kernel sampling is disabled. For fixing the potential leakage, the idea is to use instruction_pointer_set to set invalid ip address in leaked perf samples in some cases.
But instruction_pointer_set is missing on some architectures. Define instruction_pointer_set for these architectures. Signed-off-by: Jin Yao <[email protected]> --- arch/alpha/include/asm/ptrace.h | 6 ++++++ arch/arc/include/asm/ptrace.h | 6 ++++++ arch/nds32/include/asm/ptrace.h | 7 +++++++ arch/xtensa/include/asm/ptrace.h | 6 ++++++ 4 files changed, 25 insertions(+) diff --git a/arch/alpha/include/asm/ptrace.h b/arch/alpha/include/asm/ptrace.h index df5f317ab3fc..c464d525c110 100644 --- a/arch/alpha/include/asm/ptrace.h +++ b/arch/alpha/include/asm/ptrace.h @@ -25,4 +25,10 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->r0; } +static inline void instruction_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + regs->pc = val; +} + #endif diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h index 2fdb87addadc..8869a6c0fe8c 100644 --- a/arch/arc/include/asm/ptrace.h +++ b/arch/arc/include/asm/ptrace.h @@ -154,6 +154,12 @@ static inline long regs_return_value(struct pt_regs *regs) return (long)regs->r0; } +static inline void instruction_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + regs->ret = val; +} + #endif /* !__ASSEMBLY__ */ #endif /* __ASM_PTRACE_H */ diff --git a/arch/nds32/include/asm/ptrace.h b/arch/nds32/include/asm/ptrace.h index 919ee223620c..19a916bef7f5 100644 --- a/arch/nds32/include/asm/ptrace.h +++ b/arch/nds32/include/asm/ptrace.h @@ -62,6 +62,13 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) { return regs->uregs[0]; } + +static inline void instruction_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + regs->ipc = val; +} + extern void show_regs(struct pt_regs *); /* Avoid circular header include via sched.h */ struct task_struct; diff --git a/arch/xtensa/include/asm/ptrace.h b/arch/xtensa/include/asm/ptrace.h index b109416dc07e..82ab1ba99259 100644 --- a/arch/xtensa/include/asm/ptrace.h +++ b/arch/xtensa/include/asm/ptrace.h @@ -90,6 +90,12 @@ struct pt_regs { # define return_pointer(regs) (MAKE_PC_FROM_RA((regs)->areg[0], \ (regs)->areg[1])) +static inline void instruction_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + regs->pc = val; +} + # ifndef CONFIG_SMP # define profile_pc(regs) instruction_pointer(regs) # else -- 2.17.1
