From nobody Mon Dec 1 23:35:09 2025 Received: from outboundhk.mxmail.xiaomi.com (outboundhk.mxmail.xiaomi.com [207.226.244.123]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0BD933176EB for ; Wed, 26 Nov 2025 06:16:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=207.226.244.123 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764137781; cv=none; b=jzZdiu/HqWRFsumx+Rx4pH4Ys5PXknrgn7q1fNB0rw2EjLRZYKYPYmAAZlUAaII+SOORr88VjjwIV5VX1LbRTj0tYCbKmLRhRVC3AY9j0eqmNwjHwscX971FfRlXOPY+Eyu17/MzKDnHxGeuaQ04HauNs/cN7u0YkCRm+lrUhik= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764137781; c=relaxed/simple; bh=JrO37x1z7zSA2VNGX9xqDEZgYnl0mOxPDknAwJaxkw0=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=KJA/Bx9rc7Yp8TyTylpg8xAEOxC5MIKREJaTNLBnHaz2T5TBdj48iV1wfc1pZBIL06V5jYuBCdzTwnzLBhzzW6N0Z6MTZsUfRBFrozIm5bDhEhxFHV2BMYWoDxRVe8F/PpcXE96KBcjQ2ipfzTnG7f9kBWmEOQHxI6jMvNHysJ0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=xiaomi.com; spf=pass smtp.mailfrom=xiaomi.com; arc=none smtp.client-ip=207.226.244.123 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=xiaomi.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=xiaomi.com X-CSE-ConnectionGUID: SVIipR2gS8u9dkyJDBjhig== X-CSE-MsgGUID: tzX5zkejShCT7CQarabfng== X-IronPort-AV: E=Sophos;i="6.20,227,1758556800"; d="scan'208";a="159485797" From: sparkhuang To: Liam Girdwood , Mark Brown , Charles Keepax , CC: , , , sparkhuang Subject: [PATCH] regulator: core: Protect regulator_supply_alias_list with regulator_list_mutex Date: Wed, 26 Nov 2025 14:15:42 +0800 Message-ID: <20251126061542.3849-1-huangshaobo3@xiaomi.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: BJ-MBX19.mioffice.cn (10.237.8.139) To BJ-MBX01.mioffice.cn (10.237.8.121) Content-Type: text/plain; charset="utf-8" regulator_supply_alias_list was accessed without any locking in regulator_supply_alias(), regulator_register_supply_alias(), and regulator_unregister_supply_alias(). Concurrent registration, unregistration and lookups can race, leading to: 1 use-after-free if an alias entry is removed while being read, 2 duplicate entries when two threads register the same alias, 3 inconsistent alias mappings observed by consumers. Protect all traversals, insertions and deletions on regulator_supply_alias_list with the existing regulator_list_mutex. Fixes: a06ccd9c3785f ("regulator: core: Add ability to create a lookup alia= s for supply") Signed-off-by: sparkhuang --- drivers/regulator/core.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index dd7b10e768c0..e809cbae2261 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1942,6 +1942,7 @@ static void regulator_supply_alias(struct device **de= v, const char **supply) { struct regulator_supply_alias *map; =20 + mutex_lock(®ulator_list_mutex); map =3D regulator_find_supply_alias(*dev, *supply); if (map) { dev_dbg(*dev, "Mapping supply %s to %s,%s\n", @@ -1950,6 +1951,7 @@ static void regulator_supply_alias(struct device **de= v, const char **supply) *dev =3D map->alias_dev; *supply =3D map->alias_supply; } + mutex_unlock(®ulator_list_mutex); } =20 static int regulator_match(struct device *dev, const void *data) @@ -2492,22 +2494,26 @@ int regulator_register_supply_alias(struct device *= dev, const char *id, const char *alias_id) { struct regulator_supply_alias *map; + struct regulator_supply_alias *new_map; =20 - map =3D regulator_find_supply_alias(dev, id); - if (map) - return -EEXIST; - - map =3D kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL); - if (!map) + new_map =3D kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL); + if (!new_map) return -ENOMEM; =20 - map->src_dev =3D dev; - map->src_supply =3D id; - map->alias_dev =3D alias_dev; - map->alias_supply =3D alias_id; + mutex_lock(®ulator_list_mutex); + map =3D regulator_find_supply_alias(dev, id); + if (map) { + mutex_unlock(®ulator_list_mutex); + kfree(new_map); + return -EEXIST; + } =20 + new_map->src_dev =3D dev; + new_map->src_supply =3D id; + new_map->alias_dev =3D alias_dev; + new_map->alias_supply =3D alias_id; list_add(&map->list, ®ulator_supply_alias_list); - + mutex_lock(®ulator_list_mutex); pr_info("Adding alias for supply %s,%s -> %s,%s\n", id, dev_name(dev), alias_id, dev_name(alias_dev)); =20 @@ -2527,11 +2533,13 @@ void regulator_unregister_supply_alias(struct devic= e *dev, const char *id) { struct regulator_supply_alias *map; =20 + mutex_lock(®ulator_list_mutex); map =3D regulator_find_supply_alias(dev, id); if (map) { list_del(&map->list); kfree(map); } + mutex_unlock(®ulator_list_mutex); } EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias); =20 --=20 2.34.1