From nobody Sat Jul 25 06:09:49 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7771F1DDC1D; Fri, 17 Jul 2026 01:31:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784251913; cv=none; b=erF+a/G8Z2dvQyo9paaJeEpEJW0UIwtF8fS5SJbogeL6/ZTW6P65UpLF9fjg0/RXM6s53UUCJaqRQcRHvqbficLBPMA20vsgS2cWMfw8UqeippKCWOugWAfWVLVnHugyFDPuHE/OFxgt3ijLLgdW+arEEzAVFPqzmLzw0EXqOwQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784251913; c=relaxed/simple; bh=AEkH+S3LPeQIBHUnTBylYpth/yV5FHHkS+NT4XWVP9A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jpWVRbhrGXQUQfS6XmfLcER84G0B7zrKsVjMj4Nim9gE71GDRrTG2k89YOm96/LxMRBC6P4xo973jwEcxd1Aab6VWclM1WDHY1k3MaJA5Q1juOWx7veFvAMVsZnAJspMXpUlBeon0v43Deq/pideYZtcnLr2He/YikzWElTNef0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: 448e714a817f11f1aa26b74ffac11d73-20260717 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:35991573-2407-4e0b-b8bd-89724cf05bac,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:e7bac3a,CLOUDID:aedd3a298ffaf126913f01f3b9efaaa4,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:81|82|102|850|865|898,TC:nil,Content:0|1 5|50,EDM:-3,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI :0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 448e714a817f11f1aa26b74ffac11d73-20260717 X-User: yanlonglong@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1057801486; Fri, 17 Jul 2026 09:31:43 +0800 From: longlong yan To: shuah@kernel.org Cc: jkacur@redhat.com, jwyatt@redhat.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, sageofredondo@gmail.com, skhan@linuxfoundation.org, trenn@suse.com, yanlonglong@kylinos.cn Subject: [PATCH v2] cpupower/debug/i386: check mmap return value in main Date: Fri, 17 Jul 2026 09:31:25 +0800 Message-ID: <20260717013125.974-1-yanlonglong@kylinos.cn> X-Mailer: git-send-email 2.47.1.windows.2 In-Reply-To: <592b00fd-d529-4373-a733-d9f53d225540@kernel.org> References: <592b00fd-d529-4373-a733-d9f53d225540@kernel.org> 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 Content-Type: text/plain; charset="utf-8" The return value of mmap() is not checked. On failure mmap() returns MAP_FAILED, not NULL. If mmap() fails, the subsequent for-loop dereferences the invalid pointer (MAP_FAILED), causing a segfault. Add a check for MAP_FAILED after mmap(), consistent with the existing error handling style for open() in the same function. Changes in v2: - Remove trailing whitespace and blank row Fixes: 7fe2f6399a84 ("cpupowerutils - cpufrequtils extended with quite some= features") Signed-off-by: longlong yan --- tools/power/cpupower/debug/i386/dump_psb.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tools/power/cpupower/debug/i386/dump_psb.c b/tools/power/cpupo= wer/debug/i386/dump_psb.c index 6fb81b42ea61..fcbb73b48acb 100644 --- a/tools/power/cpupower/debug/i386/dump_psb.c +++ b/tools/power/cpupower/debug/i386/dump_psb.c @@ -182,6 +182,11 @@ main(int argc, char *argv[]) mem =3D mmap(mem, 0x100000 - 0xc0000, PROT_READ, MAP_SHARED, fd, 0xc0000); close(fd); =20 + if (mem =3D=3D MAP_FAILED) { + printf("Couldn't mmap /dev/mem\n"); + exit(1); + } + for (p =3D mem; p - mem < LEN; p+=3D16) { if (memcmp(p, "AMDK7PNOW!", 10) =3D=3D 0) { decode_psb(p, numpst); --=20 2.43.0