From f438d914b220051d4cbc65cbc5d98e163c85c93b Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 16 Oct 2007 01:27:49 -0700 Subject: kprobes: support kretprobe blacklist Introduce architecture dependent kretprobe blacklists to prohibit users from inserting return probes on the function in which kprobes can be inserted but kretprobes can not. This patch also removes "__kprobes" mark from "__switch_to" on x86_64 and registers "__switch_to" to the blacklist on x86-64, because that mark is to prohibit user from inserting only kretprobe. Signed-off-by: Masami Hiramatsu Cc: Prasanna S Panchamukhi Acked-by: Ananth N Mavinakayanahalli Cc: Anil S Keshavamurthy Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kprobes.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'kernel/kprobes.c') diff --git a/kernel/kprobes.c b/kernel/kprobes.c index f9798ff7899f..e3a5d817ac9b 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -716,6 +716,18 @@ int __kprobes register_kretprobe(struct kretprobe *rp) int ret = 0; struct kretprobe_instance *inst; int i; + void *addr = rp->kp.addr; + + if (kretprobe_blacklist_size) { + if (addr == NULL) + kprobe_lookup_name(rp->kp.symbol_name, addr); + addr += rp->kp.offset; + + for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { + if (kretprobe_blacklist[i].addr == addr) + return -EINVAL; + } + } rp->kp.pre_handler = pre_handler_kretprobe; rp->kp.post_handler = NULL; @@ -794,6 +806,17 @@ static int __init init_kprobes(void) INIT_HLIST_HEAD(&kretprobe_inst_table[i]); } + if (kretprobe_blacklist_size) { + /* lookup the function address from its name */ + for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { + kprobe_lookup_name(kretprobe_blacklist[i].name, + kretprobe_blacklist[i].addr); + if (!kretprobe_blacklist[i].addr) + printk("kretprobe: lookup failed: %s\n", + kretprobe_blacklist[i].name); + } + } + /* By default, kprobes are enabled */ kprobe_enabled = true; -- cgit v1.2.1