From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793207685; b=aH9tEqv/Ki/UJC43xp2Quy+4BCOky9qGVXQw+XC3VaMkLIOs27sV9E3qJBHVNWNZm07J ZNOYB5mIpXSTD+PFCo7qGWUws5pJtiYMmi4iPi3yey8rWYNS8LkO2zqqefMwVNNY1Exho ACPC7abA9qj+iHt8Q6hNBxffmPBq4hcYCsW5BBIcrQaU9Y2x+fArHglgQcMXtUB3PZwWV C4m/4ecjSNQDKSwMAUZH8v4u7mS1LTWokNzjTNdzStu/Jf1atoI5GPanJg89ziOWSj4/R g4+LABgb5Qc7iqR65Mas+Fr6x/EHT0n5QVTD4b/tE2y2T0QsQcG73Hgezr2hJZuRtkQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793207685; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=0dQN4obddbRGA3XUkBq63V1pk0kkAe8uKoQ1QI76VeI=; b=YJyOnMEXkr8h3l7yXC1yabS8bKmAv2k24ncouHX6kAd2wVV/HrMcQlvzZgDZrTBd8zB+ Akdk9O6hfmWk9Mcv3yuhTo4JVO6T1A32qojcqV7JVaGnhTxzLcubm7kKwfNghYv9VCUbB +R++PiZ8N031E43x3Rxo1DwymtoWCrJxUj5WVvjBiDKMpwtONmzvSaSdv2+lUPwoP0+zs 5Vvp38+Dax4j2AqByoS6g+pVM6uxDJAG+YnA4KsiaciRUBrvaO/4g6mP8uiJRCVDCdtgU ZOWlEV8ibn2ogc0rmKTRlnQ7+fQOchxcpMmnSDvJs/NGKAFclLAC0Y4wKKChkdISyEA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=aiZ7pQmf; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4D73606A31A; Wed, 28 Oct 2026 17:14:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=aiZ7pQmf Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E3671F01825; Wed, 28 Oct 2026 17:14:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793207684; bh=0dQN4obddbRGA3XUkBq63V1pk0kkAe8uKoQ1QI76VeI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=aiZ7pQmfwuD6GYnnCobcyTPBS5mP8Ir/nQ/WTRo/9gDrUXd0lmYdK2X+pZ4IRXlQq CJI6dMY+lab8E/g4o6MG9kUsx0+RTLAUlET/DOW79CPNXnK/W1nA0PooZiNJFeAdHP MLYuDUyc2OWbdz6YO68G+erMXKL7XX9R/xULygAM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Jose Fernandez (Anthropic)" , Ben Cressey , Mikulas Patocka Subject: [PATCH 6.12 103/247] dm-integrity: fix infinite loop on discard with large tag size Date: Wed, 28 Oct 2026 17:58:26 +0100 Message-ID: <20261028165949.836002877@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028165947.349197979@linuxfoundation.org> References: <20261028165947.349197979@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Cressey commit 18d80c77b4c7dd20699e81cedfbbff4e9d198f28 upstream. When integrity_metadata handles a discard, it fills a buffer with DISCARD_FILLER and writes it over the tags, max_blocks blocks at a time. If the kmalloc fails, the buffer is the on-stack array checksums_onstack and max_size is set to HASH_MAX_DIGESTSIZE. So if the tag size is larger than HASH_MAX_DIGESTSIZE, max_blocks is zero, bi_size is never decremented and the loop never terminates. Fix this by using sizeof(checksums_onstack) as max_size. The array has MAX_TAG_SIZE bytes since commit b93b6643e9b5 ("dm integrity: fix a crash with unusually large tag size"), so max_blocks is at least 1. Fixes: 84597a44a9d8 ("dm integrity: add optional discard support") Cc: stable@vger.kernel.org Reviewed-by: Jose Fernandez (Anthropic) Signed-off-by: Ben Cressey Assisted-by: Claude:unspecified Signed-off-by: Mikulas Patocka Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-integrity.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1856,7 +1856,7 @@ static void integrity_metadata(struct wo if (unlikely(dio->op == REQ_OP_DISCARD)) { unsigned int bi_size = dio->bio_details.bi_iter.bi_size; - unsigned int max_size = likely(checksums != checksums_onstack) ? PAGE_SIZE : HASH_MAX_DIGESTSIZE; + unsigned int max_size = likely(checksums != checksums_onstack) ? PAGE_SIZE : sizeof(checksums_onstack); unsigned int max_blocks = (max_size - extra_space) / ic->tag_size; sector_t sector = dio->range.logical_sector;