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 picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 79C13C77B60 for ; Wed, 26 Apr 2023 07:56:51 +0000 (UTC) Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 370EE3CBB62 for ; Wed, 26 Apr 2023 09:56:49 +0200 (CEST) Received: from in-3.smtp.seeweb.it (in-3.smtp.seeweb.it [IPv6:2001:4b78:1:20::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id 634123C8DAE for ; Wed, 26 Apr 2023 09:56:37 +0200 (CEST) Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by in-3.smtp.seeweb.it (Postfix) with ESMTPS id 26A4D1A000B0 for ; Wed, 26 Apr 2023 09:56:36 +0200 (CEST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 1B49C21A04; Wed, 26 Apr 2023 07:56:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1682495795; h=from:from:reply-to: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=GNMCwmw3gEWn3DZdtiSw/tddogfaAIQRHkmCZdadb/o=; b=QzagL7ggSMTy0m9zJPYikVXzB+MMjCNm8tiSMe0U/dg2U8IqZEI0OVC5oXcZI1/AVAkhhV uO9B0J0eR/7S5OfRzxKS3VjzUp7+BvhrXTF5zOSjVYxcMspeD6yHczQqvCI7NrSGvOq2gz kqeZEwZK5Amy4rnbubh1+gWIGaXh7TQ= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1682495795; h=from:from:reply-to: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=GNMCwmw3gEWn3DZdtiSw/tddogfaAIQRHkmCZdadb/o=; b=4d0iBQqBKEFH24J0e+GXEaG5gl5z2KUv9Mp/gfn08eRL/RDTFhTwyKehh7zVqLU8q+DNlj fKNuR2X+0J5FgGCg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 0885913421; Wed, 26 Apr 2023 07:56:35 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id OTYJAjPZSGTeBgAAMHmgww (envelope-from ); Wed, 26 Apr 2023 07:56:35 +0000 Date: Wed, 26 Apr 2023 09:57:38 +0200 From: Cyril Hrubis To: Martin Doucha Message-ID: References: <20230421145746.5704-1-mdoucha@suse.cz> <20230421145746.5704-3-mdoucha@suse.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230421145746.5704-3-mdoucha@suse.cz> X-Virus-Scanned: clamav-milter 0.102.4 at in-3.smtp.seeweb.it X-Virus-Status: Clean Subject: Re: [LTP] [PATCH 3/5] KVM: Fix infinite loop in ptr2hex() X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ltp@lists.linux.it, nstange@suse.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Hi! > Contrary to the C standard, (x >> 64) is equivalent to (x >> 0) on x86. As far as I can tell right shift larger than the left operand size are undefined, at least in C99. Other than that the patch looks good. Reviewed-by: Cyril Hrubis > This can cause infinite loop in ptr2hex() if the highest nibble > in the second argument is non-zero. Use temporary variable to avoid > bit-shifting by large values. > > Signed-off-by: Martin Doucha > --- > testcases/kernel/kvm/lib_guest.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/testcases/kernel/kvm/lib_guest.c b/testcases/kernel/kvm/lib_guest.c > index d237293fc..d3b2ac3d5 100644 > --- a/testcases/kernel/kvm/lib_guest.c > +++ b/testcases/kernel/kvm/lib_guest.c > @@ -82,7 +82,7 @@ char *ptr2hex(char *dest, uintptr_t val) > uintptr_t tmp; > char *ret = dest; > > - for (i = 4; val >> i; i += 4) > + for (i = 4, tmp = val >> 4; tmp; i += 4, tmp >>= 4) > ; > > do { > -- > 2.40.0 > > > -- > Mailing list info: https://lists.linux.it/listinfo/ltp -- Cyril Hrubis chrubis@suse.cz -- Mailing list info: https://lists.linux.it/listinfo/ltp