From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 361C114D6F1; Thu, 1 Aug 2024 00:40:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472818; cv=none; b=YguaOi5HC4+JedZSLX9WBmoCVer12/5xhmnVJvjjf5tcC4GJOX76lpokwPQuV8G5HEUlBS2c5r7+dnbPNZDXXALmg4JJV1oOg5PbF2pWOA46oz78E8LHN20ng4rXtK+MwkUcccmAVZ5y8pdF2SMwJBCPsmXOM2/3KX3fVZZKjlk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472818; c=relaxed/simple; bh=Hd5NowUcUAp541sQ2PvaAZrGVSsqTq0O3BLmgzGh0so=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DI3sT7ZuS0ocPWCRcHLZkIU8D7Xkcarg8v4KlA2ghfqq3Xk+xv+EEWAqlwHgUb9gK8lt1zFVt7GlD9555GtZ7sXo1GrvbbfWosSwtnq6d9hHCSTZqBulIgu45a8+KPT+MqD6gzZg7CHOr3ey+5soc/YWITtRwB3F3RKrR9voEjo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XKoSwzcX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XKoSwzcX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEDE2C4AF0C; Thu, 1 Aug 2024 00:40:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722472818; bh=Hd5NowUcUAp541sQ2PvaAZrGVSsqTq0O3BLmgzGh0so=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XKoSwzcX6mnR0Fx2zIGzViv7wDEHb1A3eUp7jo2EGP1gk6Oo3Q8SQzzQk02ER/clt Kb6i5yyjYJ65XEkkq+x5qDEFusiJcwGlCpXlp1903V13auCVptUAKTrbMjY5s2+dHK k3mNMhRqeYjKhqz5Ja50NXAN3YLgUkoxV9OKCOSBRikqpdrR1Uli3Sk7LJFdTXosef IS0EgdRvb6m9UP2kUs7g9IKaeIiZ2uU1Rpshozrd2zqKmRZG7ymiZ28kfJ8Q2VbmgL AvttMs7lw7/7Za/cTfq3GEnQrEyHXBPXIe5hd/N+Uu3uyOBPQb5KY/IKMzgnRgVnG4 CBNSD4cqCy4BQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andreas Ziegler , Daniel Borkmann , Sasha Levin , andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 21/22] libbpf: Add NULL checks to bpf_object__{prev_map,next_map} Date: Wed, 31 Jul 2024 20:38:50 -0400 Message-ID: <20240801003918.3939431-21-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240801003918.3939431-1-sashal@kernel.org> References: <20240801003918.3939431-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.281 Content-Transfer-Encoding: 8bit From: Andreas Ziegler [ Upstream commit cedc12c5b57f7efa6dbebfb2b140e8675f5a2616 ] In the current state, an erroneous call to bpf_object__find_map_by_name(NULL, ...) leads to a segmentation fault through the following call chain: bpf_object__find_map_by_name(obj = NULL, ...) -> bpf_object__for_each_map(pos, obj = NULL) -> bpf_object__next_map((obj = NULL), NULL) -> return (obj = NULL)->maps While calling bpf_object__find_map_by_name with obj = NULL is obviously incorrect, this should not lead to a segmentation fault but rather be handled gracefully. As __bpf_map__iter already handles this situation correctly, we can delegate the check for the regular case there and only add a check in case the prev or next parameter is NULL. Signed-off-by: Andreas Ziegler Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20240703083436.505124-1-ziegler.andreas@siemens.com Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b8849812449c3..98e34c5172673 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4754,7 +4754,7 @@ __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) struct bpf_map * bpf_map__next(const struct bpf_map *prev, const struct bpf_object *obj) { - if (prev == NULL) + if (prev == NULL && obj != NULL) return obj->maps; return __bpf_map__iter(prev, obj, 1); @@ -4763,7 +4763,7 @@ bpf_map__next(const struct bpf_map *prev, const struct bpf_object *obj) struct bpf_map * bpf_map__prev(const struct bpf_map *next, const struct bpf_object *obj) { - if (next == NULL) { + if (next == NULL && obj != NULL) { if (!obj->nr_maps) return NULL; return obj->maps + obj->nr_maps - 1; -- 2.43.0