[PATCH net 4/7] net: hns3: fix debugfs concurrency issue between kfree buffer and read
From: Jijie Shao <shaojijie@huawei.com>
Date: 2023-09-06 07:24:02
Also in:
lkml
Subsystem:
hisilicon network subsystem 3 driver (hns3), hisilicon network subsystem driver, networking drivers, the rest · Maintainers:
Jian Shen, Jijie Shao, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Hao Chen <redacted>
Now in hns3_dbg_uninit(), there may be concurrency between
kfree buffer and read, it may result in memory error.
Moving debugfs_remove_recursive() in front of kfree buffer to ensure
they don't happen at the same time.
Fixes: 5e69ea7ee2a6 ("net: hns3: refactor the debugfs process")
Signed-off-by: Hao Chen <redacted>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
---
drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
index 8086722a56c0..b8508533878b 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c@@ -1415,9 +1415,9 @@ int hns3_dbg_init(struct hnae3_handle *handle) return 0; out: - mutex_destroy(&handle->dbgfs_lock); debugfs_remove_recursive(handle->hnae3_dbgfs); handle->hnae3_dbgfs = NULL; + mutex_destroy(&handle->dbgfs_lock); return ret; }
@@ -1425,6 +1425,9 @@ void hns3_dbg_uninit(struct hnae3_handle *handle) { u32 i; + debugfs_remove_recursive(handle->hnae3_dbgfs); + handle->hnae3_dbgfs = NULL; + for (i = 0; i < ARRAY_SIZE(hns3_dbg_cmd); i++) if (handle->dbgfs_buf[i]) { kvfree(handle->dbgfs_buf[i]);
@@ -1432,8 +1435,6 @@ void hns3_dbg_uninit(struct hnae3_handle *handle) } mutex_destroy(&handle->dbgfs_lock); - debugfs_remove_recursive(handle->hnae3_dbgfs); - handle->hnae3_dbgfs = NULL; } void hns3_dbg_register_debugfs(const char *debugfs_dir_name)
--
2.30.0