Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4178C40F754; Thu, 20 Aug 2026 16:44:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787244275; cv=none; b=u70FREP7YWKuZVEZpMgS1rNLHlGBFoE0gnR5Fyl6GaFH73RrR1HbzZLp6tybx3XHnOXCEiBMqcmmt8/B/MqF362lvFsw1WN3pK4cajDSpuUupKwjFTDodhgcJ8ab++9KcYq0mvui9GnDzLFJ2iq5dR1lm6O6GZzlMSAC6xkDH1U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787244275; c=relaxed/simple; bh=twI1ejmJXonc7GeBgdzo2AG+Zc8h7KgCtai0ovC81eM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ijFIq1w58YN/DC7TLpzE8CqI7ZstdziqwjfAmmDZfGE5KGC3BsH5UxdVUbm/6wwnfrECUxgBxO74m+uRLMs6ZVnilT9k3nT84TEpkYDswR0EjqieLuPTyCFJvhnfXIbJE8AXZqtcC3gP6f+93dIJdHvETLce5oSzHn+aXZB5X8g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lK2nHdW5; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lK2nHdW5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 94EAB1F000E9; Thu, 20 Aug 2026 16:44:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787244274; bh=dg886dHpxt/+VAR5tA0Jc4a3UrN03AiQnS7e7dkiK38=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=lK2nHdW58v42YaaSyyHL7GxQDJ3qzQbDB8Uv5R7z75aXOTRzFBj0X+fNBwYQC8Gwi OASQc1TsCl9kweL/zi+PtJ0s8exUI1v5IqCRhOMGF1dqovPzTO+2qfa4VPlu5Xwl4M T32AePDNkit+dK9LaK1Ep4RLsSAL2N3ru5+7qthQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mikulas Patocka , Sasha Levin Subject: [PATCH 5.10 113/235] dm-verity: make error counter atomic Date: Thu, 20 Aug 2026 16:55:49 +0200 Message-ID: <20260820145219.879876660@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145216.426568665@linuxfoundation.org> References: <20260820145216.426568665@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka [ Upstream commit 8ec4d9c5a5cf4b61fc087f871465b1f79b393325 ] The error counter "v->corrupted_errs" was not atomic, thus it could be subject to race conditions. The call to dm_audit_log_target("max-corrupted-errors") may be skipped due to the races. Signed-off-by: Mikulas Patocka Assisted-by: Claude:claude-opus-4.6 Fixes: 65ff5b7ddf05 ("dm verity: add error handling modes for corrupted blocks") Cc: stable@vger.kernel.org [ kept 5.15's braceless single-statement DMERR body instead of upstream's braced block containing the absent dm_audit_log_target() call ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-verity-target.c | 12 +++++++----- drivers/md/dm-verity.h | 2 +- 2 files changed, 8 insertions(+), 6 deletions(-) --- a/drivers/md/dm-verity-target.c +++ b/drivers/md/dm-verity-target.c @@ -217,14 +217,16 @@ static int verity_handle_err(struct dm_v char *envp[] = { verity_env, NULL }; const char *type_str = ""; struct mapped_device *md = dm_table_get_md(v->ti->table); + int ce; /* Corruption should be visible in device status in all modes */ v->hash_failed = 1; - if (v->corrupted_errs >= DM_VERITY_MAX_CORRUPTED_ERRS) - goto out; - - v->corrupted_errs++; + ce = atomic_read(&v->corrupted_errs); + do { + if (ce >= DM_VERITY_MAX_CORRUPTED_ERRS) + goto out; + } while (!atomic_try_cmpxchg(&v->corrupted_errs, &ce, ce + 1)); switch (type) { case DM_VERITY_BLOCK_TYPE_DATA: @@ -240,7 +242,7 @@ static int verity_handle_err(struct dm_v DMERR_LIMIT("%s: %s block %llu is corrupted", v->data_dev->name, type_str, block); - if (v->corrupted_errs == DM_VERITY_MAX_CORRUPTED_ERRS) + if (ce + 1 == DM_VERITY_MAX_CORRUPTED_ERRS) DMERR("%s: reached maximum errors", v->data_dev->name); snprintf(verity_env, DM_VERITY_ENV_LENGTH, "%s=%d,%llu", --- a/drivers/md/dm-verity.h +++ b/drivers/md/dm-verity.h @@ -55,7 +55,7 @@ struct dm_verity { unsigned int ahash_reqsize;/* the size of temporary space for crypto */ int hash_failed; /* set to 1 if hash of any block failed */ enum verity_mode mode; /* mode for handling verification errors */ - unsigned corrupted_errs;/* Number of errors for corrupted blocks */ + atomic_t corrupted_errs;/* Number of errors for corrupted blocks */ struct workqueue_struct *verify_wq;