From 637247403abff8c963bc7be8002b3f49ea604563 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 17 Apr 2014 17:18:49 +0900 Subject: [PATCH] kprobes: Show blacklist entries via debugfs Show blacklist entries (function names with the address range) via /sys/kernel/debug/kprobes/blacklist. Note that at this point the blacklist supports only in vmlinux, not module. So the list is fixed and not updated. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Anil S Keshavamurthy Cc: David S. Miller Link: http://lkml.kernel.org/r/20140417081849.26341.11609.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar --- kernel/kprobes.c | 61 +++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 53 insertions(+), 8 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index a21b4e67fd97..3214289df5a7 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2249,6 +2249,46 @@ static const struct file_operations debugfs_kprobes_operations = { .release = seq_release, }; +/* kprobes/blacklist -- shows which functions can not be probed */ +static void *kprobe_blacklist_seq_start(struct seq_file *m, loff_t *pos) +{ + return seq_list_start(&kprobe_blacklist, *pos); +} + +static void *kprobe_blacklist_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &kprobe_blacklist, pos); +} + +static int kprobe_blacklist_seq_show(struct seq_file *m, void *v) +{ + struct kprobe_blacklist_entry *ent = + list_entry(v, struct kprobe_blacklist_entry, list); + + seq_printf(m, "0x%p-0x%p\t%ps\n", (void *)ent->start_addr, + (void *)ent->end_addr, (void *)ent->start_addr); + return 0; +} + +static const struct seq_operations kprobe_blacklist_seq_ops = { + .start = kprobe_blacklist_seq_start, + .next = kprobe_blacklist_seq_next, + .stop = kprobe_seq_stop, /* Reuse void function */ + .show = kprobe_blacklist_seq_show, +}; + +static int kprobe_blacklist_open(struct inode *inode, struct file *filp) +{ + return seq_open(filp, &kprobe_blacklist_seq_ops); +} + +static const struct file_operations debugfs_kprobe_blacklist_ops = { + .open = kprobe_blacklist_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + static void arm_all_kprobes(void) { struct hlist_head *head; @@ -2372,19 +2412,24 @@ static int __init debugfs_kprobe_init(void) file = debugfs_create_file("list", 0444, dir, NULL, &debugfs_kprobes_operations); - if (!file) { - debugfs_remove(dir); - return -ENOMEM; - } + if (!file) + goto error; file = debugfs_create_file("enabled", 0600, dir, &value, &fops_kp); - if (!file) { - debugfs_remove(dir); - return -ENOMEM; - } + if (!file) + goto error; + + file = debugfs_create_file("blacklist", 0444, dir, NULL, + &debugfs_kprobe_blacklist_ops); + if (!file) + goto error; return 0; + +error: + debugfs_remove(dir); + return -ENOMEM; } late_initcall(debugfs_kprobe_init); -- 2.30.2