From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) (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 85ADB381D9 for ; Mon, 1 Jul 2024 10:17:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719829068; cv=none; b=ZU/kIFTQpGiw3XgwFy1pxXxtCLcZEih+DSl7PV2kVe11srV53wMaG3368MTWEWXrZrNL6rE/Ubw3rV2ErhCPu1WjtDCz0mct12MxUY7TuTOZ1SLakgk95ezawbjdLCsasN3c/z3XK6d2x1ggzqZmD3pn4BKEj0PMYbRljsGX+m8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719829068; c=relaxed/simple; bh=gD5VNciUmya9nnktxztF3YVxZqyKDZW7Eo+EKHt/dOI=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=ZQmfFaMUFYCqPADcc+5s5+t86ZHeZOICZhGzA3bmZmvLJPFrGXP21IzpBpvBV5NEDtH4wqbso4fgakoM5A9UafTKrt6dZ7zGcPiTITnkG1l1s7PrQM6y+7EDICX5hRzlr9FN5vPyaw+lPW9tqIzlDbQzNZ9OFk5nwrdkNRPKQns= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f69.google.com with SMTP id ca18e2360f4ac-7f6218c0d68so321644239f.3 for ; Mon, 01 Jul 2024 03:17:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719829066; x=1720433866; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=brX9ipQBvZqJcUy+uAGuKNo04VrHpo2fWqw9e458zqU=; b=iyiWxS1W16hZvoVzxmgti1OhWHhzbXA6cYKhUSCy993L51trJqibLBNhGhL/z5mY8g 31KTs7xlwLbweHPxjxZMYkRf+zl6nsWF8AF3j5U/aa0KXxwgK3zdtImjc+VFq33pWhtg FpzQwmWv6ee2rteb9++d0q/+YREuDacENdCP8HARpJkFQWl34cLUv3RW+L46Xm8aZCMS WyDLGQCg72LxsD5Vtz6xItpPESIXD7T4rmy8dC2HfMQ1ISyB3gOvwnP+ONMegkmHCWRO m93mcwjhIvx4tN6cwC2W67LrhVvy20Dh+rx8dqUQFEzTYqq5rF+83rMQY/0cDypvEAg/ 4kZA== X-Gm-Message-State: AOJu0YzwJdFgx0ffhmd5Xe7jPNAEd+QC9MoO4zNH7oJI19MaUNlgKFOf gBRoLlLJSBUjrIWx5n+kZ+2QW/C0o0nWApJKEyaZFcbeF2pwnz5ZveNKKFb751Lp7sf7LMN3kFE xK3xAzsaAtS1W4u0QavvtWBy4DE9zaqC69Mybke2JSfZVvSYHeZwpi5A= X-Google-Smtp-Source: AGHT+IESwWqAFL0WRbaHYTHTs5/LZCYswVwyly+ZCxAmQva/cgh8xqdYM1LnCtyXF26nEVhuR+4CwwjD47E8sPyfHZAPgwRTeNi8 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6602:1511:b0:7f6:1b69:a0cc with SMTP id ca18e2360f4ac-7f62eeab21fmr29792939f.4.1719829065732; Mon, 01 Jul 2024 03:17:45 -0700 (PDT) Date: Mon, 01 Jul 2024 03:17:45 -0700 In-Reply-To: <000000000000fb15d306134ae036@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000089ab17061c2ce84a@google.com> Subject: Re: [syzbot] [syzbot] [bpf?] [net?] KMSAN: uninit-value in bpf_prog_test_run_xdp From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com. *** Subject: [syzbot] [bpf?] [net?] KMSAN: uninit-value in bpf_prog_test_run_xdp Author: wojciech.gladysz@infogain.com #syz test: https://linux.googlesource.com/linux/kernel/git/torvalds/linux e478cf26c556e4ab572ab0ab2306c986901dcd61 --- kernel/bpf/verifier.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 36ef8e96787e..13a9c2e2908a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7146,8 +7146,8 @@ static int check_stack_range_initialized( * reads. However, if raw_mode is not set, we'll do extra * checks below. */ - bounds_check_type = BPF_WRITE; - clobber = true; + clobber = !meta || meta->raw_mode; + bounds_check_type = clobber ? BPF_WRITE : BPF_READ; } else { bounds_check_type = BPF_READ; } @@ -7230,8 +7230,7 @@ static int check_stack_range_initialized( stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE]; if (*stype == STACK_MISC) goto mark; - if ((*stype == STACK_ZERO) || - (*stype == STACK_INVALID && env->allow_uninit_stack)) { + if (*stype == STACK_ZERO) { if (clobber) { /* helper can write anything into the stack */ *stype = STACK_MISC; @@ -8748,6 +8747,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, meta->map_uid = reg->map_uid; break; case ARG_PTR_TO_MAP_KEY: + /* always mark read access */ + meta->raw_mode = false; /* bpf_map_xxx(..., map_ptr, ..., key) call: * check that [key, key + map->key_size) are within * stack limits and initialized @@ -8763,7 +8764,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, } err = check_helper_mem_access(env, regno, meta->map_ptr->key_size, false, - NULL); + meta); break; case ARG_PTR_TO_MAP_VALUE: if (type_may_be_null(arg_type) && register_is_null(reg)) -- 2.35.3