From patchwork Tue May 17 07:36:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugene Syromiatnikov X-Patchwork-Id: 573577 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD1E8C433FE for ; Tue, 17 May 2022 07:36:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241459AbiEQHgp (ORCPT ); Tue, 17 May 2022 03:36:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242296AbiEQHg3 (ORCPT ); Tue, 17 May 2022 03:36:29 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BC1AD1027 for ; Tue, 17 May 2022 00:36:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652772987; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=0xxKQ63UkLF4342r+f5JL5hPNHBH+mdnNusP1wdNqn8=; b=B3j15HsxWOvLQdCN1uurV10ay7SnFtNtLZCKmhFZ3w+REuArZfJR+7c61UafD24bqEfd5z EOHhmP/Mz3GWNgo2ZsBqo1aLD7OOqcD6xDHbKLlCtclCUa3lH4hVd3hdE8bjWGcdzHiuDy vexs/J9KMOujw0zbugL/0n8/q4NFsq4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-252-rN0cl44rNQqwRZrePtyRQg-1; Tue, 17 May 2022 03:36:22 -0400 X-MC-Unique: rN0cl44rNQqwRZrePtyRQg-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E9A19299E75D; Tue, 17 May 2022 07:36:21 +0000 (UTC) Received: from asgard.redhat.com (unknown [10.36.110.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0443E5739A1; Tue, 17 May 2022 07:36:17 +0000 (UTC) Date: Tue, 17 May 2022 09:36:15 +0200 From: Eugene Syromiatnikov To: Jiri Olsa , Masami Hiramatsu , Steven Rostedt , Ingo Molnar , Alexei Starovoitov , Daniel Borkmann Cc: Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Shuah Khan , linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v3 1/4] bpf_trace: check size for overflow in bpf_kprobe_multi_link_attach Message-ID: <9e4171972a3d75e656073e0c25cd4071a6f652e4.1652772731.git.esyr@redhat.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Check that size would not overflow before calculation (and return -EOVERFLOW if it will), to prevent potential out-of-bounds write with the following copy_from_user. Use kvmalloc_array in copy_user_syms to prevent out-of-bounds write into syms (and especially buf) as well. Fixes: 0dcac272540613d4 ("bpf: Add multi kprobe link") Cc: # 5.18 Signed-off-by: Eugene Syromiatnikov --- kernel/trace/bpf_trace.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 7141ca8..9c041be 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2261,11 +2261,11 @@ static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 int err = -ENOMEM; unsigned int i; - syms = kvmalloc(cnt * sizeof(*syms), GFP_KERNEL); + syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL); if (!syms) goto error; - buf = kvmalloc(cnt * KSYM_NAME_LEN, GFP_KERNEL); + buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL); if (!buf) goto error; @@ -2461,7 +2461,8 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr if (!cnt) return -EINVAL; - size = cnt * sizeof(*addrs); + if (check_mul_overflow(cnt, (u32)sizeof(*addrs), &size)) + return -EOVERFLOW; addrs = kvmalloc(size, GFP_KERNEL); if (!addrs) return -ENOMEM; From patchwork Tue May 17 07:36:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugene Syromiatnikov X-Patchwork-Id: 573576 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 845F5C433FE for ; Tue, 17 May 2022 07:37:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241606AbiEQHg7 (ORCPT ); Tue, 17 May 2022 03:36:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241557AbiEQHgu (ORCPT ); Tue, 17 May 2022 03:36:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 089354839F for ; Tue, 17 May 2022 00:36:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652773007; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=pQ8Tbw3YXlfFnImshaS6CSiXIKXl6akxMQXuGl5HlAA=; b=H7jSsizinrG8nZErCw/ytFK20Fk3uOSAT2IHyDT5nRYZp/cDlb+P32jQqxa9JFRXytViAh 1Hap16PZJPyckgYQGkbAILxVl34BM1rAPYTKYhThRRwEJh1H1NBEsL4QVRcRnOqZh32VSz MGM0WqFckrFENZCR4mqZ2R8G2JqJj44= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-556-Mlcp5x2wPqa4VISOC-SGlw-1; Tue, 17 May 2022 03:36:44 -0400 X-MC-Unique: Mlcp5x2wPqa4VISOC-SGlw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 404C9101AA47; Tue, 17 May 2022 07:36:43 +0000 (UTC) Received: from asgard.redhat.com (unknown [10.36.110.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 771137774; Tue, 17 May 2022 07:36:39 +0000 (UTC) Date: Tue, 17 May 2022 09:36:36 +0200 From: Eugene Syromiatnikov To: Jiri Olsa , Masami Hiramatsu , Steven Rostedt , Ingo Molnar , Alexei Starovoitov , Daniel Borkmann Cc: Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Shuah Khan , linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v3 3/4] bpf_trace: handle compat in copy_user_syms Message-ID: <2a56d66cf4b9430982e81233f49d6c54988df056.1652772731.git.esyr@redhat.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org For compat processes, userspace size for syms pointers is different. Provide compat handling for copying array elements from the user space. Fixes: 0dcac272540613d4 ("bpf: Add multi kprobe link") Signed-off-by: Eugene Syromiatnikov --- kernel/trace/bpf_trace.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a93a54f..9d3028a 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2253,6 +2253,24 @@ struct user_syms { char *buf; }; +static inline int get_arr_ptr(unsigned long *p, + unsigned long __user *uaddr, u32 idx) +{ + if (unlikely(in_compat_syscall())) { + compat_uptr_t __user *compat_uaddr = (compat_uptr_t __user *)uaddr; + compat_uptr_t val; + int err; + + err = __get_user(val, compat_uaddr + idx); + if (!err) + *p = val; + + return err; + } else { + return __get_user(*p, uaddr + idx); + } +} + static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt) { unsigned long __user usymbol; @@ -2270,7 +2288,7 @@ static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 goto error; for (p = buf, i = 0; i < cnt; i++) { - if (__get_user(usymbol, usyms + i)) { + if (get_arr_ptr(&usymbol, usyms, i)) { err = -EFAULT; goto error; } From patchwork Tue May 17 07:36:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugene Syromiatnikov X-Patchwork-Id: 573575 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78834C433F5 for ; Tue, 17 May 2022 07:38:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242038AbiEQHit (ORCPT ); Tue, 17 May 2022 03:38:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241783AbiEQHhn (ORCPT ); Tue, 17 May 2022 03:37:43 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 72B4A49251 for ; Tue, 17 May 2022 00:37:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652773022; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Mqoy+gV+cPqf1cM9iO48i7hrZpV+uT4NBe8cPuE9DHk=; b=SwnnjIZcpPHjxUB6/MyNj/MHr3fdxrx1HOzMxLvkf0eBUJpE5r5PYZVBda4uhBLFXoi4YA hCp0vnYqtLXw+0h5HUStoml7T8jAusdVnXs2j+Mv2fKaXDhcXDXXxgDsgrb/Q6HiVNhQFE Oe0i87th5+oYUkxo1U4RRhPuJgD+gh8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-88-cZvUbg2HOE6qVtAgQLSAdg-1; Tue, 17 May 2022 03:36:55 -0400 X-MC-Unique: cZvUbg2HOE6qVtAgQLSAdg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0DF6F299E751; Tue, 17 May 2022 07:36:54 +0000 (UTC) Received: from asgard.redhat.com (unknown [10.36.110.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2B55215687CF; Tue, 17 May 2022 07:36:49 +0000 (UTC) Date: Tue, 17 May 2022 09:36:47 +0200 From: Eugene Syromiatnikov To: Jiri Olsa , Masami Hiramatsu , Steven Rostedt , Ingo Molnar , Alexei Starovoitov , Daniel Borkmann Cc: Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Shuah Khan , linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v3 4/4] bpf_trace: pass array of u64 values in kprobe_multi.addrs Message-ID: <6ef675aeeea442fa8fc168cd1cb4e4e474f65a3f.1652772731.git.esyr@redhat.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org With the interface as defined, it is impossible to pass 64-bit kernel addresses from a 32-bit userspace process in BPF_LINK_TYPE_KPROBE_MULTI, which severly limits the useability of the interface, change the ABI to accept an array of u64 values instead of (kernel? user?) longs. Interestingly, the rest of the libbpf infrastructure uses 64-bit values for kallsyms addresses already, so this patch also eliminates the sym_addr cast in tools/lib/bpf/libbpf.c:resolve_kprobe_multi_cb(). Fixes: 0dcac272540613d4 ("bpf: Add multi kprobe link") Fixes: 5117c26e877352bc ("libbpf: Add bpf_link_create support for multi kprobes") Fixes: ddc6b04989eb0993 ("libbpf: Add bpf_program__attach_kprobe_multi_opts function") Fixes: f7a11eeccb111854 ("selftests/bpf: Add kprobe_multi attach test") Fixes: 9271a0c7ae7a9147 ("selftests/bpf: Add attach test for bpf_program__attach_kprobe_multi_opts") Fixes: 2c6401c966ae1fbe ("selftests/bpf: Add kprobe_multi bpf_cookie test") Signed-off-by: Eugene Syromiatnikov --- kernel/trace/bpf_trace.c | 25 ++++++++++++++++++---- tools/lib/bpf/bpf.h | 2 +- tools/lib/bpf/libbpf.c | 8 +++---- tools/lib/bpf/libbpf.h | 2 +- .../testing/selftests/bpf/prog_tests/bpf_cookie.c | 2 +- .../selftests/bpf/prog_tests/kprobe_multi_test.c | 8 +++---- 6 files changed, 32 insertions(+), 15 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 9d3028a..30a15b3 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2454,7 +2454,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr void __user *ucookies; unsigned long *addrs; u32 flags, cnt, size, cookies_size; - void __user *uaddrs; + u64 __user *uaddrs; u64 *cookies = NULL; void __user *usyms; int err; @@ -2486,9 +2486,26 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr return -ENOMEM; if (uaddrs) { - if (copy_from_user(addrs, uaddrs, size)) { - err = -EFAULT; - goto error; + if (sizeof(*addrs) == sizeof(*uaddrs)) { + if (copy_from_user(addrs, uaddrs, size)) { + err = -EFAULT; + goto error; + } + } else { + u32 i; + u64 addr; + + for (i = 0; i < cnt; i++) { + if (get_user(addr, uaddrs + i)) { + err = -EFAULT; + goto error; + } + if (addr > ULONG_MAX) { + err = -EINVAL; + goto error; + } + addrs[i] = addr; + } } } else { struct user_syms us; diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 2e0d373..da9c6037 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -418,7 +418,7 @@ struct bpf_link_create_opts { __u32 flags; __u32 cnt; const char **syms; - const unsigned long *addrs; + const __u64 *addrs; const __u64 *cookies; } kprobe_multi; struct { diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ef7f302..35fa9c5 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -10737,7 +10737,7 @@ static bool glob_match(const char *str, const char *pat) struct kprobe_multi_resolve { const char *pattern; - unsigned long *addrs; + __u64 *addrs; size_t cap; size_t cnt; }; @@ -10752,12 +10752,12 @@ resolve_kprobe_multi_cb(unsigned long long sym_addr, char sym_type, if (!glob_match(sym_name, res->pattern)) return 0; - err = libbpf_ensure_mem((void **) &res->addrs, &res->cap, sizeof(unsigned long), + err = libbpf_ensure_mem((void **) &res->addrs, &res->cap, sizeof(__u64), res->cnt + 1); if (err) return err; - res->addrs[res->cnt++] = (unsigned long) sym_addr; + res->addrs[res->cnt++] = sym_addr; return 0; } @@ -10772,7 +10772,7 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, }; struct bpf_link *link = NULL; char errmsg[STRERR_BUFSIZE]; - const unsigned long *addrs; + const __u64 *addrs; int err, link_fd, prog_fd; const __u64 *cookies; const char **syms; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 9e9a3fd..76e171d 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -489,7 +489,7 @@ struct bpf_kprobe_multi_opts { /* array of function symbols to attach */ const char **syms; /* array of function addresses to attach */ - const unsigned long *addrs; + const __u64 *addrs; /* array of user-provided values fetchable through bpf_get_attach_cookie */ const __u64 *cookies; /* number of elements in syms/addrs/cookies arrays */ diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c index 83ef55e3..e843840 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c @@ -140,7 +140,7 @@ static void kprobe_multi_link_api_subtest(void) cookies[6] = 7; cookies[7] = 8; - opts.kprobe_multi.addrs = (const unsigned long *) &addrs; + opts.kprobe_multi.addrs = (const __u64 *) &addrs; opts.kprobe_multi.cnt = ARRAY_SIZE(addrs); opts.kprobe_multi.cookies = (const __u64 *) &cookies; prog_fd = bpf_program__fd(skel->progs.test_kprobe); diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index 586dc52..7646112 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -108,7 +108,7 @@ static void test_link_api_addrs(void) GET_ADDR("bpf_fentry_test7", addrs[6]); GET_ADDR("bpf_fentry_test8", addrs[7]); - opts.kprobe_multi.addrs = (const unsigned long*) addrs; + opts.kprobe_multi.addrs = (const __u64 *) addrs; opts.kprobe_multi.cnt = ARRAY_SIZE(addrs); test_link_api(&opts); } @@ -186,7 +186,7 @@ static void test_attach_api_addrs(void) GET_ADDR("bpf_fentry_test7", addrs[6]); GET_ADDR("bpf_fentry_test8", addrs[7]); - opts.addrs = (const unsigned long *) addrs; + opts.addrs = (const __u64 *) addrs; opts.cnt = ARRAY_SIZE(addrs); test_attach_api(NULL, &opts); } @@ -244,7 +244,7 @@ static void test_attach_api_fails(void) goto cleanup; /* fail_2 - both addrs and syms set */ - opts.addrs = (const unsigned long *) addrs; + opts.addrs = (const __u64 *) addrs; opts.syms = syms; opts.cnt = ARRAY_SIZE(syms); opts.cookies = NULL; @@ -258,7 +258,7 @@ static void test_attach_api_fails(void) goto cleanup; /* fail_3 - pattern and addrs set */ - opts.addrs = (const unsigned long *) addrs; + opts.addrs = (const __u64 *) addrs; opts.syms = NULL; opts.cnt = ARRAY_SIZE(syms); opts.cookies = NULL;