From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- include/soc/qcom/cmd-db.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 include/soc/qcom/cmd-db.h (limited to 'include/soc/qcom/cmd-db.h') diff --git a/include/soc/qcom/cmd-db.h b/include/soc/qcom/cmd-db.h new file mode 100644 index 000000000..47a6cab75 --- /dev/null +++ b/include/soc/qcom/cmd-db.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. + * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#ifndef __QCOM_COMMAND_DB_H__ +#define __QCOM_COMMAND_DB_H__ + +#include + +enum cmd_db_hw_type { + CMD_DB_HW_INVALID = 0, + CMD_DB_HW_MIN = 3, + CMD_DB_HW_ARC = CMD_DB_HW_MIN, + CMD_DB_HW_VRM = 4, + CMD_DB_HW_BCM = 5, + CMD_DB_HW_MAX = CMD_DB_HW_BCM, + CMD_DB_HW_ALL = 0xff, +}; + +#if IS_ENABLED(CONFIG_QCOM_COMMAND_DB) +u32 cmd_db_read_addr(const char *resource_id); + +const void *cmd_db_read_aux_data(const char *resource_id, size_t *len); + +bool cmd_db_match_resource_addr(u32 addr1, u32 addr2); + +enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id); + +int cmd_db_ready(void); +#else +static inline u32 cmd_db_read_addr(const char *resource_id) +{ return 0; } + +static inline const void *cmd_db_read_aux_data(const char *resource_id, size_t *len) +{ return ERR_PTR(-ENODEV); } + +static inline bool cmd_db_match_resource_addr(u32 addr1, u32 addr2) +{ return false; } + +static inline enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id) +{ return -ENODEV; } + +static inline int cmd_db_ready(void) +{ return -ENODEV; } +#endif /* CONFIG_QCOM_COMMAND_DB */ +#endif /* __QCOM_COMMAND_DB_H__ */ -- cgit v1.3.1