From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 379BB2DB7B9; Thu, 11 Jun 2026 05:59:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.21 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781157597; cv=none; b=I8KnFzsyV7vTDtgvdFZWOSMSuvoYxN/GV8sTIzjshmWp1Qhm6kx9eYrOo9dou22TB3LGAnIwW0st+xPTZ5Whip1jE8lB5vEAcnh5sYdb11xeVZdxFmzaL9a/i0OSyrmh9rw4bnzNMF9D/TOhct/eEjmkGcylXSfxTBYGa39+CZs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781157597; c=relaxed/simple; bh=xIWDsWMDfzSC9s4Hxf2T695OOeCQGjh3p+/FrdCRcZ8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=tijsdrP7RSqLSKuqfxkKeTn0kl7jj5DrZPE4c2GlUykLttDEYnopptHOSp0X0lSYyBC7zY/yODSWsowV5kU6hIj7hPOWJ0VWq5DFC59pgRqwCx3+tYG1xkEGyZrCiLOMDkym/jqoFOzCTikmXK6cbyyX+RHIKwQ2DTaMLjgNKXE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [111.196.245.140]) by APP-01 (Coremail) with SMTP id qwCowACXPdbTTipqvyxFAQ--.9346S4; Thu, 11 Jun 2026 13:59:48 +0800 (CST) From: Pengpeng Hou To: Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers Cc: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, Pengpeng Hou Subject: [PATCH v5 2/3] tracing: Return ERR_PTR() from expr_str() Date: Thu, 11 Jun 2026 13:59:44 +0800 Message-ID: <20260611055945.22348-3-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:qwCowACXPdbTTipqvyxFAQ--.9346S4 X-Coremail-Antispam: 1UD129KBjvJXoWxWr4fXF18tr43KFW3tFyUGFg_yoW5XFyDpF 4kXwnIg3ykJF4Ig343AF48u3W3G393Gr4UGF97uay0yrnxKr48Xa1UWF1UX34SvrW0qrW3 JF4UZrZ8Cr42gFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBl14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l84 ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkF7I0En4kS14v26r126r1DMx AIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_ Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwI xGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWx JwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcV C2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7VUULZ2DUUUUU== X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ expr_str() currently reports all failure cases as NULL, so callers cannot distinguish invalid recursion depth from allocation failure or later string construction errors. Return ERR_PTR()-encoded errors from expr_str() and make parse_unary() and parse_expr() propagate them. Clear expr->name before destroying the hist field so the error pointer is not freed as a string. Signed-off-by: Pengpeng Hou --- kernel/trace/trace_events_hist.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index f778f060e922..082842e64ccd 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1762,11 +1762,11 @@ static char *expr_str(struct hist_field *field, unsigned int level) char *expr __free(kfree) = NULL; if (level > 1) - return NULL; + return ERR_PTR(-EINVAL); expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); if (!expr) - return NULL; + return ERR_PTR(-ENOMEM); if (!field->operands[0]) { expr_field_str(field, expr); @@ -1778,8 +1778,8 @@ static char *expr_str(struct hist_field *field, unsigned int level) strcat(expr, "-("); subexpr = expr_str(field->operands[0], ++level); - if (!subexpr) - return NULL; + if (IS_ERR(subexpr)) + return subexpr; strcat(expr, subexpr); strcat(expr, ")"); @@ -1805,7 +1805,7 @@ static char *expr_str(struct hist_field *field, unsigned int level) strcat(expr, "*"); break; default: - return NULL; + return ERR_PTR(-EINVAL); } expr_field_str(field->operands[1], expr); @@ -2624,6 +2624,11 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, expr->is_signed = operand1->is_signed; expr->operator = FIELD_OP_UNARY_MINUS; expr->name = expr_str(expr, 0); + if (IS_ERR(expr->name)) { + ret = PTR_ERR(expr->name); + expr->name = NULL; + goto free; + } expr->type = kstrdup_const(operand1->type, GFP_KERNEL); if (!expr->type) { ret = -ENOMEM; @@ -2836,6 +2841,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, destroy_hist_field(operand1, 0); expr->name = expr_str(expr, 0); + if (IS_ERR(expr->name)) { + ret = PTR_ERR(expr->name); + expr->name = NULL; + goto free_expr; + } } else { /* The operand sizes should be the same, so just pick one */ expr->size = operand1->size; @@ -2849,6 +2859,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, } expr->name = expr_str(expr, 0); + if (IS_ERR(expr->name)) { + ret = PTR_ERR(expr->name); + expr->name = NULL; + goto free_expr; + } } return expr; -- 2.50.1 (Apple Git-155)