From nobody Wed Apr 1 20:39:01 2026 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 0262C391E4D for ; Wed, 1 Apr 2026 16:03:23 +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=1775059406; cv=none; b=Y6ek2D9vN+KpPOMG+/EYfnh7lb+ASJAKEk5aZW5YUqSWyETUMmboV/KtQqy75uIUvkJmhP22K6vb66cGTGz3UZrehPK96/ch0Hxg9saAXfiOfqgJ8vTzS6q//0Nnwe7rBpCcadnM+QPGbJ/+TshHSePgSTBTjz5uQgN5ul3fv3s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775059406; c=relaxed/simple; bh=AkbZDcHVBus6FnKmS3PikdcjXcF5U3wrNIONzdt3arc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=OU8lLuQGB0F3E7MMo8DNJ0gpAqx3SoRkmZU0Q+GrGLCTRTF8VKZAWHFcgw+EI+WBwV5W1J2UrTzh2LCM4FBTgJ7Uodhh2pSuiKX+2sdu9OjU3vOI9Mn9t/4FWQlni1sdfK8U9vaMzVxUfWBt2zhxaEoYmu8uu52nMURvB6Hn5jM= 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 [111.196.245.197]) by APP-01 (Coremail) with SMTP id qwCowAC3XWnEQc1p7hThCw--.21092S2; Thu, 02 Apr 2026 00:03:17 +0800 (CST) From: Pengpeng Hou To: maddy@linux.ibm.com Cc: mpe@ellerman.id.au, npiggin@gmail.com, chleroy@kernel.org, srikar@linux.ibm.com, sshegde@linux.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, pengpeng@iscas.ac.cn Subject: [PATCH] powerpc/rtas_flash: bound validate-flash message strings Date: Thu, 2 Apr 2026 00:03:16 +0800 Message-ID: <20260401160316.88567-1-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: qwCowAC3XWnEQc1p7hThCw--.21092S2 X-Coremail-Antispam: 1UD129KBjvJXoW7CFy3WF1furyUJF47Gr4DArb_yoW8JFWfp3 sYkrW7tas8JFWrJF9rtrn3uF4YgayDJFyfWF4qk34kA3W2qFyvgFn5W34xtr4qgF1ktr1r ua1DtF1YgF1Yg37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkK14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26r1j6r4UM28EF7xvwVC2z280aVCY1x0267AKxVW8JV W8Jr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_JF0_Jw1lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lc7CjxVAaw2AFwI0_ Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67 AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIY rxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E14 v26F4j6r4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_ Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7VUbtxhJ UUUUU== X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ Content-Type: text/plain; charset="utf-8" get_validate_flash_msg() appends args_buf->buf to the userspace-visible status message with a plain %s conversion. The firmware validation path copies a full 4096-byte buffer through args_buf->buf, so the status message builder can walk past the end of that fixed buffer looking for a terminator. Limit the appended message to the validated buffer size. Signed-off-by: Pengpeng Hou --- arch/powerpc/kernel/rtas_flash.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/rtas_flash.c b/arch/powerpc/kernel/rtas_fl= ash.c index 583dc16e9d3c..5b3c6f3a11cd 100644 --- a/arch/powerpc/kernel/rtas_flash.c +++ b/arch/powerpc/kernel/rtas_flash.c @@ -455,8 +455,10 @@ static int get_validate_flash_msg(struct rtas_validate= _flash_t *args_buf, n =3D sprintf(msg, "%d\n", args_buf->update_results); if ((args_buf->update_results >=3D VALIDATE_CUR_UNKNOWN) || (args_buf->update_results =3D=3D VALIDATE_TMP_UPDATE)) - n +=3D snprintf(msg + n, msglen - n, "%s\n", - args_buf->buf); + n +=3D snprintf(msg + n, msglen - n, "%.*s\n", + (int)strnlen(args_buf->buf, + args_buf->buf_size), + args_buf->buf); } else { n =3D sprintf(msg, "%d\n", args_buf->status); } --=20 2.50.1 (Apple Git-155)