From mboxrd@z Thu Jan 1 00:00:00 1970 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 76C86C433EF for ; Fri, 19 Nov 2021 21:13:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234733AbhKSVPk (ORCPT ); Fri, 19 Nov 2021 16:15:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:38666 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234002AbhKSVPe (ORCPT ); Fri, 19 Nov 2021 16:15:34 -0500 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0DB6961AFB; Fri, 19 Nov 2021 21:12:29 +0000 (UTC) Date: Fri, 19 Nov 2021 16:12:28 -0500 From: Steven Rostedt To: Linus Torvalds Cc: LKML , Ingo Molnar , Andrew Morton , Kalesh Singh , Kees Cook , Nikita Yushchenko Subject: [GIT PULL] tracing: Histogram fix take two and two more fixes Message-ID: <20211119161228.18322a90@gandalf.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Tracing fixes: - Fix double free in destroy_hist_field - Harden memset() of trace_iterator structure - Do not warn in trace printk check when test buffer fills up Please pull the latest trace-v5.16-6 tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git trace-v5.16-6 Tag SHA1: 61ba32adb5e7d2d6534234bd22bd43a259419187 Head SHA1: 2ef75e9bd2c998f1c6f6f23a3744136105ddefd5 Kalesh Singh (1): tracing/histogram: Fix UAF in destroy_hist_field() Kees Cook (1): tracing: Use memset_startat() to zero struct trace_iterator Nikita Yushchenko (1): tracing: Don't use out-of-sync va_list in event printing ---- kernel/trace/trace.c | 16 +++++++++++++--- kernel/trace/trace_events_hist.c | 41 +++++++++++++++++++++------------------- 2 files changed, 35 insertions(+), 22 deletions(-) --------------------------- diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f9139dc1262c..88de94da596b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3812,6 +3812,18 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, iter->fmt[i] = '\0'; trace_seq_vprintf(&iter->seq, iter->fmt, ap); + /* + * If iter->seq is full, the above call no longer guarantees + * that ap is in sync with fmt processing, and further calls + * to va_arg() can return wrong positional arguments. + * + * Ensure that ap is no longer used in this case. + */ + if (iter->seq.full) { + p = ""; + break; + } + if (star) len = va_arg(ap, int); @@ -6706,9 +6718,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, cnt = PAGE_SIZE - 1; /* reset all but tr, trace, and overruns */ - memset(&iter->seq, 0, - sizeof(struct trace_iterator) - - offsetof(struct trace_iterator, seq)); + memset_startat(iter, 0, seq); cpumask_clear(iter->started); trace_seq_init(&iter->seq); iter->pos = -1; diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 5ea2c9ec54a6..9555b8e1d1e3 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -2576,28 +2576,27 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, /* Split the expression string at the root operator */ if (!sep) - goto free; + return ERR_PTR(-EINVAL); + *sep = '\0'; operand1_str = str; str = sep+1; /* Binary operator requires both operands */ if (*operand1_str == '\0' || *str == '\0') - goto free; + return ERR_PTR(-EINVAL); operand_flags = 0; /* LHS of string is an expression e.g. a+b in a+b+c */ operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); - if (IS_ERR(operand1)) { - ret = PTR_ERR(operand1); - operand1 = NULL; - goto free; - } + if (IS_ERR(operand1)) + return ERR_CAST(operand1); + if (operand1->flags & HIST_FIELD_FL_STRING) { hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); ret = -EINVAL; - goto free; + goto free_op1; } /* RHS of string is another expression e.g. c in a+b+c */ @@ -2605,13 +2604,12 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); if (IS_ERR(operand2)) { ret = PTR_ERR(operand2); - operand2 = NULL; - goto free; + goto free_op1; } if (operand2->flags & HIST_FIELD_FL_STRING) { hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); ret = -EINVAL; - goto free; + goto free_operands; } switch (field_op) { @@ -2629,12 +2627,12 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, break; default: ret = -EINVAL; - goto free; + goto free_operands; } ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); if (ret) - goto free; + goto free_operands; operand_flags = var1 ? var1->flags : operand1->flags; operand2_flags = var2 ? var2->flags : operand2->flags; @@ -2653,12 +2651,13 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, expr = create_hist_field(hist_data, NULL, flags, var_name); if (!expr) { ret = -ENOMEM; - goto free; + goto free_operands; } operand1->read_once = true; operand2->read_once = true; + /* The operands are now owned and free'd by 'expr' */ expr->operands[0] = operand1; expr->operands[1] = operand2; @@ -2669,7 +2668,7 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, if (!divisor) { hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); ret = -EDOM; - goto free; + goto free_expr; } /* @@ -2709,18 +2708,22 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, expr->type = kstrdup_const(operand1->type, GFP_KERNEL); if (!expr->type) { ret = -ENOMEM; - goto free; + goto free_expr; } expr->name = expr_str(expr, 0); } return expr; -free: - destroy_hist_field(operand1, 0); + +free_operands: destroy_hist_field(operand2, 0); - destroy_hist_field(expr, 0); +free_op1: + destroy_hist_field(operand1, 0); + return ERR_PTR(ret); +free_expr: + destroy_hist_field(expr, 0); return ERR_PTR(ret); }