From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Thu, 14 Jul 2022 10:09:53 +0200 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oBtuz-007LaY-Nt for lore@lore.pengutronix.de; Thu, 14 Jul 2022 10:09:53 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oBtux-0000tz-Fw for lore@pengutronix.de; Thu, 14 Jul 2022 10:09:52 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:From:In-Reply-To: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4FD5vh8nO30B2twt67OGh51YqCeDPZLPRd11hUClHEI=; b=ebLgsqN9J/DLkxGXkEtBwRxhQE K61dSEkUgOZN9HNp6Qd+QZt5SIHAVowrYg35bjxlF10qwrShYv9IkQcn6KsqOKjDCej9Q3DbnX09u R44IH6WcByY7BHG8V4/jgteAwK8MnzOnhRS+ECAlYdmirGtn3UEIbPQUZ+IAxuFtQn0rgkUp7y2oC QbU8fe9LiodiVcqbeCVNLnhFPiiYzv3HJ4V5QypwJ2EhghiaClliLZfNkh7c+Dip9k7kop29scPdb Vw6UF1+pGt9YoylgSBkF6+ngljY8GeQdjc3OekoauZ4GRCaWG4N2wEBQTr7D0QINjvAmzuSp3yYdx kQK4Wc4w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oBttd-00CBoj-Rq; Thu, 14 Jul 2022 08:08:29 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oBttZ-00CBln-AB for barebox@lists.infradead.org; Thu, 14 Jul 2022 08:08:26 +0000 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oBttU-0000lB-CZ; Thu, 14 Jul 2022 10:08:20 +0200 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1oBttU-0003fG-45; Thu, 14 Jul 2022 10:08:20 +0200 Date: Thu, 14 Jul 2022 10:08:20 +0200 To: Ahmad Fatoum Cc: barebox@lists.infradead.org Message-ID: <20220714080820.GH23482@pengutronix.de> References: <20220713092047.1588210-1-a.fatoum@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220713092047.1588210-1-a.fatoum@pengutronix.de> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) From: Sascha Hauer X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220714_010825_368865_1917EF63 X-CRM114-Status: GOOD ( 22.57 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-4.1 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH master] ubifs: fix crash building without decompressors X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) On Wed, Jul 13, 2022 at 11:20:47AM +0200, Ahmad Fatoum wrote: > When building barebox with ubifs support, but without decompressors > enabled, we run into a NULL pointer dereference: > > BUG: failure at lib/string.c:249/strncmp()! > BUG! > [<4fd8ea59>] (unwind_backtrace+0x1/0x78) from [<4fd014e5>] (panic+0x1d/0x34) > [<4fd014e5>] (panic+0x1d/0x34) from [<4fd65ed1>] (strncmp+0x2d/0x50) > [<4fd65ed1>] (strncmp+0x2d/0x50) from [<4fd784bb>] (compr_init+0x4b/0x70) > [<4fd784bb>] (compr_init+0x4b/0x70) from [<4fd78915>] (ubifs_compressors_init+0x15/0x40) > [<4fd78915>] (ubifs_compressors_init+0x15/0x40) from [<4fd78e89>] (ubifs_init+0x2d/0x48) > [<4fd78e89>] (ubifs_init+0x2d/0x48) from [<4fd01159>] (start_barebox+0x35/0x6c) > [<4fd01159>] (start_barebox+0x35/0x6c) from [<4fd8c9f3>] (barebox_non_pbl_start+0x127/0x170) > [<4fd8c9f3>] (barebox_non_pbl_start+0x127/0x170) from [<4fd00005>] (__bare_init_start+0x1/0xc) > > This is because the loop in crypto_alloc_comp iterates over all possible > decompressors and then accesses comp->capi_name, which will be NULL for > unusable decompressors. Add a NULL check to handle this gracefully. > A check for alg_name isn't needed because it's already checked in > compr_init. > > Signed-off-by: Ahmad Fatoum > --- > fs/ubifs/ubifs.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Applied, thanks Sascha > > diff --git a/fs/ubifs/ubifs.c b/fs/ubifs/ubifs.c > index e7b434c1960e..0b4f3de773e7 100644 > --- a/fs/ubifs/ubifs.c > +++ b/fs/ubifs/ubifs.c > @@ -125,7 +125,8 @@ static inline struct crypto_comp > i++; > continue; > } > - if (strncmp(alg_name, comp->capi_name, strlen(alg_name)) == 0) { > + if (comp->capi_name && > + strncmp(alg_name, comp->capi_name, strlen(alg_name)) == 0) { > ptr->compressor = i; > return ptr; > } > -- > 2.30.2 > > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |