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 7D9DE218339; Wed, 23 Oct 2024 14:33:27 +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=1729694007; cv=none; b=kjZoY463+QQ/CmdSn1xbUFJjn8qLxZIJgvdxodI33CgxfpUplgo3sgUk/G9Eyp+x/zihHcIDuEBFxwT3IyunzkHKKNcGhRxtuhpd4YQ6c1kO9Yc2RmLqrbMRajN5Ac7/Xv2TORKEHV0msXA8D2NDXYI2KfvAmEGOYAO93m2CVoU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729694007; c=relaxed/simple; bh=ehKCRv5eADkou1azTYF5vkSU2N2nnR4vZ3u/U0CdpgM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NAbJlx/KssApTXDsWrCFMSiUVVYKqVvnKUBxZIMvK/Xf59CYGb/vnMc8jLc//8r8m/3oXhSmiI2ah4/g/Wjs7YMlq6x7OSpFm3//TqGYH5Y+5F469vDj9rzYSxp3utdte/9T09QrqlXR+GPCD/0yqiZE6+ZNc97LsbuYSu1nTe8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TeFd2p4R; 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="TeFd2p4R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B082C4CECD; Wed, 23 Oct 2024 14:33:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729694007; bh=ehKCRv5eADkou1azTYF5vkSU2N2nnR4vZ3u/U0CdpgM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TeFd2p4RhRlN8zkAxm7eEhzIUvJ6LfW6oYhKI2w/nKF5nw48s3/yKazdqRQcUFw8R Opb/Ln4ElOGkL5LuNCIQSBAqHfPaAzVuW6PM7/Ccvd5TainWOUkuYrbRFL7kMuEukX ZTowY9YLrH0yIYxFjuIsaEFo+rVohEdG3NWTLC18vRQSX9vTAknAOKCy7OwCw2LOm4 EToc+H+iMQIfLXfqP0CANGIuVRwtgMYRIIZYlieG9V4px9B3qZersyzyYtyyABLlqb GuPg6qIyeJfZ3NmtCHplhZab0ELqTv28yKqakl44QjoJvfQpvQBm4IcexXL9Ocx+Aw Cxa7F0gx67xrA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Rik van Riel , Shakeel Butt , Alexei Starovoitov , Sasha Levin , daniel@iogearbox.net, andrii@kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 3/5] bpf: use kvzmalloc to allocate BPF verifier environment Date: Wed, 23 Oct 2024 10:33:18 -0400 Message-ID: <20241023143321.2982841-3-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241023143321.2982841-1-sashal@kernel.org> References: <20241023143321.2982841-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.19.322 Content-Transfer-Encoding: 8bit From: Rik van Riel [ Upstream commit 434247637c66e1be2bc71a9987d4c3f0d8672387 ] The kzmalloc call in bpf_check can fail when memory is very fragmented, which in turn can lead to an OOM kill. Use kvzmalloc to fall back to vmalloc when memory is too fragmented to allocate an order 3 sized bpf verifier environment. Admittedly this is not a very common case, and only happens on systems where memory has already been squeezed close to the limit, but this does not seem like much of a hot path, and it's a simple enough fix. Signed-off-by: Rik van Riel Reviewed-by: Shakeel Butt Link: https://lore.kernel.org/r/20241008170735.16766766@imladris.surriel.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- kernel/bpf/verifier.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index a48de55f5630e..de0926cff8352 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -6446,7 +6446,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) /* 'struct bpf_verifier_env' can be global, but since it's not small, * allocate/free it every time bpf_check() is called */ - env = kzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL); + env = kvzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL); if (!env) return -ENOMEM; log = &env->log; @@ -6573,6 +6573,6 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) mutex_unlock(&bpf_verifier_lock); vfree(env->insn_aux_data); err_free_env: - kfree(env); + kvfree(env); return ret; } -- 2.43.0