From 9fd112b1f82b587ffb12fb67dd032f551fdb571a Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Fri, 19 Jan 2024 12:04:59 +0100 Subject: bpf: Store cookies in kprobe_multi bpf_link_info data Storing cookies in kprobe_multi bpf_link_info data. The cookies field is optional and if provided it needs to be an array of __u64 with kprobe_multi.count length. Acked-by: Yafang Shao Signed-off-by: Jiri Olsa Acked-by: Song Liu Link: https://lore.kernel.org/r/20240119110505.400573-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- kernel/trace/bpf_trace.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 7ac6c52b25eb..c98c20abaf99 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2679,6 +2679,7 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { + u64 __user *ucookies = u64_to_user_ptr(info->kprobe_multi.cookies); u64 __user *uaddrs = u64_to_user_ptr(info->kprobe_multi.addrs); struct bpf_kprobe_multi_link *kmulti_link; u32 ucount = info->kprobe_multi.count; @@ -2686,6 +2687,8 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, if (!uaddrs ^ !ucount) return -EINVAL; + if (ucookies && !ucount) + return -EINVAL; kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); info->kprobe_multi.count = kmulti_link->cnt; @@ -2699,6 +2702,18 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, else ucount = kmulti_link->cnt; + if (ucookies) { + if (kmulti_link->cookies) { + if (copy_to_user(ucookies, kmulti_link->cookies, ucount * sizeof(u64))) + return -EFAULT; + } else { + for (i = 0; i < ucount; i++) { + if (put_user(0, ucookies + i)) + return -EFAULT; + } + } + } + if (kallsyms_show_value(current_cred())) { if (copy_to_user(uaddrs, kmulti_link->addrs, ucount * sizeof(u64))) return -EFAULT; -- cgit v1.2.3