From 659b957f20c78fd470083c80af5e79eedfb39e5b Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Fri, 7 Jul 2017 22:37:24 +0530 Subject: kprobes: Rename [arch_]function_offset_within_entry() to [arch_]kprobe_on_func_entry() Rename function_offset_within_entry() to scope it to kprobe namespace by using kprobe_ prefix, and to also simplify it. Suggested-by: Ingo Molnar Suggested-by: Masami Hiramatsu Signed-off-by: Naveen N. Rao Cc: Ananth N Mavinakayanahalli Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/3aa6c7e2e4fb6e00f3c24fa306496a66edb558ea.1499443367.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- kernel/kprobes.c | 8 ++++---- kernel/trace/trace_kprobe.c | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 6756d750b31b..a519219169fd 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1888,12 +1888,12 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) } NOKPROBE_SYMBOL(pre_handler_kretprobe); -bool __weak arch_function_offset_within_entry(unsigned long offset) +bool __weak arch_kprobe_on_func_entry(unsigned long offset) { return !offset; } -bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset) +bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset) { kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset); @@ -1901,7 +1901,7 @@ bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym, unsign return false; if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset) || - !arch_function_offset_within_entry(offset)) + !arch_kprobe_on_func_entry(offset)) return false; return true; @@ -1914,7 +1914,7 @@ int register_kretprobe(struct kretprobe *rp) int i; void *addr; - if (!function_offset_within_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset)) + if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset)) return -EINVAL; if (kretprobe_blacklist_size) { diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index b53c8d369163..2c5221819be5 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -720,7 +720,7 @@ static int create_trace_kprobe(int argc, char **argv) return ret; } if (offset && is_return && - !function_offset_within_entry(NULL, symbol, offset)) { + !kprobe_on_func_entry(NULL, symbol, offset)) { pr_info("Given offset is not valid for return probe.\n"); return -EINVAL; } -- cgit v1.2.3-59-g8ed1b From 0f73ff80b751b39ff539a550e65c5bd131ff0316 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Fri, 7 Jul 2017 22:37:25 +0530 Subject: kprobes: Simplify register_jprobes() Re-factor jprobe registration functions as the current version is getting too unwieldy. Move the actual jprobe registration to register_jprobe() and re-organize code accordingly. Suggested-by: Ingo Molnar Signed-off-by: Naveen N. Rao Cc: Ananth N Mavinakayanahalli Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/089cae4bfe73767f765291ee0e6fb0c3d240e5f1.1499443367.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- kernel/kprobes.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/kernel/kprobes.c b/kernel/kprobes.c index a519219169fd..db3cd3e60bdd 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1771,24 +1771,13 @@ unsigned long __weak arch_deref_entry_point(void *entry) int register_jprobes(struct jprobe **jps, int num) { - struct jprobe *jp; int ret = 0, i; if (num <= 0) return -EINVAL; + for (i = 0; i < num; i++) { - unsigned long addr, offset; - jp = jps[i]; - addr = arch_deref_entry_point(jp->entry); - - /* Verify probepoint is a function entry point */ - if (kallsyms_lookup_size_offset(addr, NULL, &offset) && - offset == 0) { - jp->kp.pre_handler = setjmp_pre_handler; - jp->kp.break_handler = longjmp_break_handler; - ret = register_kprobe(&jp->kp); - } else - ret = -EINVAL; + ret = register_jprobe(jps[i]); if (ret < 0) { if (i > 0) @@ -1796,13 +1785,26 @@ int register_jprobes(struct jprobe **jps, int num) break; } } + return ret; } EXPORT_SYMBOL_GPL(register_jprobes); int register_jprobe(struct jprobe *jp) { - return register_jprobes(&jp, 1); + unsigned long addr, offset; + struct kprobe *kp = &jp->kp; + + /* Verify probepoint is a function entry point */ + addr = arch_deref_entry_point(jp->entry); + + if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0) { + kp->pre_handler = setjmp_pre_handler; + kp->break_handler = longjmp_break_handler; + return register_kprobe(kp); + } + + return -EINVAL; } EXPORT_SYMBOL_GPL(register_jprobe); -- cgit v1.2.3-59-g8ed1b From dbf580623d5fee785218d1a47a2bcdf36d85c0e9 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Fri, 7 Jul 2017 22:37:26 +0530 Subject: kprobes: Ensure that jprobe probepoints are at function entry Similar to commit 90ec5e89e393c ("kretprobes: Ensure probe location is at function entry"), ensure that the jprobe probepoint is at function entry. Signed-off-by: Naveen N. Rao Cc: Ananth N Mavinakayanahalli Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/a4525af6c5a42df385efa31251246cf7cca73598.1499443367.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- kernel/kprobes.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/kprobes.c b/kernel/kprobes.c index db3cd3e60bdd..a1606a4224e1 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1795,10 +1795,14 @@ int register_jprobe(struct jprobe *jp) unsigned long addr, offset; struct kprobe *kp = &jp->kp; - /* Verify probepoint is a function entry point */ + /* + * Verify probepoint as well as the jprobe handler are + * valid function entry points. + */ addr = arch_deref_entry_point(jp->entry); - if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0) { + if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0 && + kprobe_on_func_entry(kp->addr, kp->symbol_name, kp->offset)) { kp->pre_handler = setjmp_pre_handler; kp->break_handler = longjmp_break_handler; return register_kprobe(kp); -- cgit v1.2.3-59-g8ed1b