From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9A8311632E7; Wed, 27 May 2026 20:10:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779912604; cv=none; b=CS0kcwavPRJv6DZ/8yvH/rRL1TUM+Hx9H9XRVILFSatv3oa/Uhq4w/vcXxH+MZLM65KQQYFR0hicC2e2WlQmlbjItzF/gTv513JOxUuLXOoZ4LY+0UXhVmCEA/7KstWR5MLWZtph84jorkGMv5XcirbLtPy+A7DCssSlcrrgtXg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779912604; c=relaxed/simple; bh=z3v5geP4eAKTBlJkF++zavVX2Gcyuvmfdpk74NxFxho=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ITQdk9nzDg2ZD0z4KTyzszMij56ksQoI9Ht2Mq2mcdA5lhuSbk0+tag4TrPCcl+OQ8A55ha2YbIJ56hgFQ6mJZFFAGel5hF/zdkKgopHD7kF2P2Nb9bYSzvpEQai3CMJVsGEEy+1m+5qaExBBLOL6bMxclc09/OOZveVLiyRFmg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hlG7Bzvw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hlG7Bzvw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 448A31F000E9; Wed, 27 May 2026 20:09:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779912603; bh=H5Z4ARx03OBFgTDhNknOHWXfPOP7tDx5AxIk0S8sS74=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=hlG7BzvwVlbl+7oOOM9vAEreMs4Sk8Uxd+lGROE2dNwYE6UiMrJd9lKXeTXX1tvJa g8EMREXiBinKdu+Er2yJauBXSH/mmIGLI2getLX2MUkZJVtiasfl9H0gBM6dSF4M/n CsFiVxLTvMyJi0QRnM0Z4z5VmfHCJcDeO0oP9MDt86jNRBoZsLz9UphDJoV1oOWl8b hs7cXBBdAP3p7pRmRjyvbjh25iaavwd7txqzilOrJ+DheFF1uQefOnY3Yi2UUIahLQ hqQEvQi3qzUomo7O7dRoQo20T3M40xV/YZ/eILqicZ+ESZ9W2SQXiXyIy9Q5zQ5JXp U4s2I7aT1ifKA== Date: Wed, 27 May 2026 16:09:57 -0400 From: Steven Rostedt To: Jens Remus Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org, Josh Poimboeuf , Indu Bhagat , Peter Zijlstra , Dylan Hatch , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Mathieu Desnoyers , Kees Cook , Sam James , bpf@vger.kernel.org, linux-mm@kvack.org, Namhyung Kim , Andrii Nakryiko , "Jose E. Marchesi" , Beau Belgrave , Florian Weimer , "Carlos O'Donell" , Masami Hiramatsu , Jiri Olsa , Arnaldo Carvalho de Melo , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich , "Steven Rostedt (Google)" Subject: Re: [PATCH v16 02/20] unwind_user/sframe: Add support for reading .sframe headers Message-ID: <20260527160957.1d3751b1@fedora> In-Reply-To: <20260521142546.3908498-3-jremus@linux.ibm.com> References: <20260521142546.3908498-1-jremus@linux.ibm.com> <20260521142546.3908498-3-jremus@linux.ibm.com> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 21 May 2026 16:25:28 +0200 Jens Remus wrote: > +static int sframe_read_header(struct sframe_section *sec) > +{ > + unsigned long header_end, fdes_start, fdes_end, fres_start, fres_end; > + struct sframe_header shdr; > + unsigned int num_fdes; > + > + if (copy_from_user(&shdr, (void __user *)sec->sframe_start, sizeof(shdr))) { > + dbg("header usercopy failed\n"); > + return -EFAULT; > + } > + > + if (shdr.preamble.magic != SFRAME_MAGIC || > + shdr.preamble.version != SFRAME_VERSION_3 || > + !(shdr.preamble.flags & SFRAME_F_FDE_SORTED) || > + !(shdr.preamble.flags & SFRAME_F_FDE_FUNC_START_PCREL) || > + shdr.auxhdr_len) { > + dbg("bad/unsupported sframe header\n"); > + return -EINVAL; > + } > + > + if (!shdr.num_fdes || !shdr.num_fres) { > + dbg("no fde/fre entries\n"); > + return -EINVAL; > + } > + > + header_end = sec->sframe_start + SFRAME_HEADER_SIZE(shdr); > + if (header_end >= sec->sframe_end) { > + dbg("header doesn't fit in section\n"); > + return -EINVAL; > + } > + > + num_fdes = shdr.num_fdes; > + fdes_start = header_end + shdr.fdes_off; > + fdes_end = fdes_start + (num_fdes * sizeof(struct sframe_fde_v3)); > + > + fres_start = header_end + shdr.fres_off; > + fres_end = fres_start + shdr.fre_len; > + > + if (fres_start < fdes_end || fres_end > sec->sframe_end) { > + dbg("inconsistent fde/fre offsets\n"); > + return -EINVAL; > + } I really think we should also test if fres_start >= fres_end. Because if fres_start is near sec->sframe_end and on 32bit archs fre_len makes fres_end overflow, this doesn't catch it. Even if it doesn't cause issues later, I rather have it caught here. -- Steve > + > + sec->num_fdes = num_fdes; > + sec->fdes_start = fdes_start; > + sec->fres_start = fres_start; > + sec->fres_end = fres_end; > + > + sec->ra_off = shdr.cfa_fixed_ra_offset; > + sec->fp_off = shdr.cfa_fixed_fp_offset; > + > + return 0; > +}