From 73266fc1df2f94cf72b3beba3eee3b88ed0b0664 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 22 Apr 2010 05:05:45 +0200 Subject: [PATCH] hw-breakpoints: Tag ptrace breakpoint as exclude_kernel Tag ptrace breakpoints with the exclude_kernel attribute set. This will make it easier to set generic policies on breakpoints, when it comes to ensure nobody unpriviliged try to breakpoint on the kernel. Signed-off-by: Frederic Weisbecker Acked-by: Paul Mundt Cc: Will Deacon Cc: Mahesh Salgaonkar Cc: K. Prasad Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Ingo Molnar --- arch/sh/kernel/ptrace_32.c | 2 +- arch/x86/kernel/ptrace.c | 2 +- include/linux/hw_breakpoint.h | 6 ++++++ 3 files changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c index 7759a9a93211..d4104ce9fe53 100644 --- a/arch/sh/kernel/ptrace_32.c +++ b/arch/sh/kernel/ptrace_32.c @@ -85,7 +85,7 @@ static int set_single_step(struct task_struct *tsk, unsigned long addr) bp = thread->ptrace_bps[0]; if (!bp) { - hw_breakpoint_init(&attr); + ptrace_breakpoint_init(&attr); attr.bp_addr = addr; attr.bp_len = HW_BREAKPOINT_LEN_2; diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 055be0afd330..70c4872cd8aa 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -688,7 +688,7 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr, struct perf_event_attr attr; if (!t->ptrace_bps[nr]) { - hw_breakpoint_init(&attr); + ptrace_breakpoint_init(&attr); /* * Put stub len and type to register (reserve) an inactive but * correct bp diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h index c70d27af03f9..a0aa5a9cfb0e 100644 --- a/include/linux/hw_breakpoint.h +++ b/include/linux/hw_breakpoint.h @@ -34,6 +34,12 @@ static inline void hw_breakpoint_init(struct perf_event_attr *attr) attr->sample_period = 1; } +static inline void ptrace_breakpoint_init(struct perf_event_attr *attr) +{ + hw_breakpoint_init(attr); + attr->exclude_kernel = 1; +} + static inline unsigned long hw_breakpoint_addr(struct perf_event *bp) { return bp->attr.bp_addr; -- 2.30.2