From nobody Sat Feb 7 20:37:54 2026 Received: from mail-lj1-f175.google.com (mail-lj1-f175.google.com [209.85.208.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5FFC38820 for ; Fri, 21 Jun 2024 18:39:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.175 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718995180; cv=none; b=YS3YW7caKrk2F4YrYX6Vg38fyYyLlflZQnh1+7SGzHXJaxIFBEQf/DYDtdXQORv+aIwR+a7vlDeTNB8yCsrrq693jETU1mKoCutYpV6azoLqBEfj62POGWxgV28GPVffuTuhsYF/hhxscYyhdPrZJHB+jsDBsFbxMTPRBVOt/bk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718995180; c=relaxed/simple; bh=vk/96ebJdlrFYsAS4ze4k3Afxi/LqFG7BOkjBpAeEIY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iQ78tm2gmuAj+6Xa1p8jA2qYjwXIkshq1AdGPHAhuaOo5DgkROJdPi/b26zZba7jV3QIX/cjzRpfu/XqD5wlmmIfgH40+8eSjixM3nOOqaqZRL6NX64Plyxupz0065hg0bVsBii6uNwgeEZbEV3fLw8lk7gURUxtp6VECLru/wI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=e0b2f9cf; arc=none smtp.client-ip=209.85.208.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="e0b2f9cf" Received: by mail-lj1-f175.google.com with SMTP id 38308e7fff4ca-2ec0f3b9cfeso24833551fa.0 for ; Fri, 21 Jun 2024 11:39:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1718995176; x=1719599976; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=ofwRrZgwZaii+MzrCdAU3E+RPpHqrKQd5gwF5AP5IBM=; b=e0b2f9cfIvPWCGf5ezi6ldOVZOwcvZtrvCRdV1SCYZ6ROWfYR4gZETsuZTKxZiqY/G lmL1cI6Xc0XJv0xKU0PP32sA8ijWY3FoO7YGYYLA3gMqsmNC+kZVIlEyOaPD8v4Gszwy PcV/xO76bU8Efmp/OyGJqLAtFlmytwZfq4bykP/Or6BDXpzVyZIfuJ6ekXz0obiZnZkM 6D+E+VFQGipcgi/fzIMGJYyBA2lJKlwqQovstwTZ56Qa6srExRJUDlScOckpx7B8zagb JbzI39OaHuyXzo5H/8c0iXEhgk0PzyWJ59UI1fbah3rlA30mMdxAY/iM/kImmDt7rINn k7rw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718995176; x=1719599976; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ofwRrZgwZaii+MzrCdAU3E+RPpHqrKQd5gwF5AP5IBM=; b=aT/NhPz0IKgJxzmBuDsgUXESPZ3djIttbtxZmPvwgueZR/DHse5RyVdxzLgJyIgvUL IOOM7Y5dICTvokMM/UdSV2zEPmc7wu0im0yT6EAGYCgaxaeP549GxbMAO8+uVOhKCCBp 8+z1EJPKUipmnTaNy+C0vcb5rqrEeIg+J+Al43ZZ9YAurfWWyejApLLOx3TLYhh1PvEn gZ3hh8ZTry/6zTpuxlz62vYodFG1NmERNhOhvV6wI/iR216LfgVceQzA48or2Y9Jmz+w qZeFzeZQxfMF7n8Kv+xE4iNhqUNNzYo1dipNlk641hWmaY5VvgLTqz/2yyU1+d4W1yWQ faZw== X-Gm-Message-State: AOJu0YwREn0OlIUMQvVX8tVaOzM1O2p9OR5UPHmeGGnJuWVc293efy5c Z/EDxq3MRTgYZOkjjG7vNc/YU0RYQydkIW8uiTOCaaV9UdAJIpNjI9DR X-Google-Smtp-Source: AGHT+IFst6jGed7IuNe8/zIF6HN4oXgeWh43JaLVtvkJ9zBZZLcLs96R8jDsu9y/SudXgTpx23Qq8g== X-Received: by 2002:a2e:978e:0:b0:2ec:5430:7f6b with SMTP id 38308e7fff4ca-2ec5430dbc1mr2325451fa.49.1718995176102; Fri, 21 Jun 2024 11:39:36 -0700 (PDT) Received: from p183 ([46.53.254.81]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-57d305353f1sm1256384a12.76.2024.06.21.11.39.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Jun 2024 11:39:35 -0700 (PDT) Date: Fri, 21 Jun 2024 21:39:33 +0300 From: Alexey Dobriyan To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Jiri Olsa Subject: [PATCH v2] build-id: require program headers to be right after ELF header Message-ID: References: <0e13fa2e-2d1c-4dac-968e-b1a0c7a05229@p183> <20240621100752.ea87e0868591dd3f49bbd271@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240621100752.ea87e0868591dd3f49bbd271@linux-foundation.org> Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Neither ELF spec not ELF loader require program header to be placed right after ELF header, but build-id code very much assumes such placement: See find_get_page(vma->vm_file->f_mapping, 0); line and checks against PAGE_SIZE.=20 Returns errors for now until someone rewrites build-id parser to be more inline with load_elf_binary(). Signed-off-by: Alexey Dobriyan Acked-by: Andrii Nakryiko Reviewed-by: Jiri Olsa --- lib/buildid.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/lib/buildid.c +++ b/lib/buildid.c @@ -73,6 +73,13 @@ static int get_build_id_32(const void *page_addr, unsign= ed char *build_id, Elf32_Phdr *phdr; int i; =20 + /* + * FIXME + * Neither ELF spec nor ELF loader require that program headers + * start immediately after ELF header. + */ + if (ehdr->e_phoff !=3D sizeof(Elf32_Ehdr)) + return -EINVAL; /* only supports phdr that fits in one page */ if (ehdr->e_phnum > (PAGE_SIZE - sizeof(Elf32_Ehdr)) / sizeof(Elf32_Phdr)) @@ -98,6 +105,13 @@ static int get_build_id_64(const void *page_addr, unsig= ned char *build_id, Elf64_Phdr *phdr; int i; =20 + /* + * FIXME + * Neither ELF spec nor ELF loader require that program headers + * start immediately after ELF header. + */ + if (ehdr->e_phoff !=3D sizeof(Elf64_Ehdr)) + return -EINVAL; /* only supports phdr that fits in one page */ if (ehdr->e_phnum > (PAGE_SIZE - sizeof(Elf64_Ehdr)) / sizeof(Elf64_Phdr))