[PATCH 5.15 114/120] i2c: npcm7xx: Fix error handling in npcm_i2c_init()

Greg Kroah-Hartman
2022-12-05T19:40:45Z

From: Yuan Can <yuancan@huawei.com>

[ Upstream commit 145900cf91c4b32ac05dbc8675a0c7f4a278749d ]

A problem about i2c-npcm7xx create debugfs failed is triggered with the
following log given:

[ 173.827310] debugfs: Directory 'npcm_i2c' with parent '/' already present!

The reason is that npcm_i2c_init() returns platform_driver_register()
directly without checking its return value, if platform_driver_register()
failed, it returns without destroy the newly created debugfs, resulting
the debugfs of npcm_i2c can never be created later.

npcm_i2c_init()
debugfs_create_dir() # create debugfs directory
platform_driver_register()
driver_register()
bus_add_driver()
priv = kzalloc(...) # OOM happened
# return without destroy debugfs directory

Fix by removing debugfs when platform_driver_register() returns error.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Tali Perry <tali.perry@nuvoton.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/busses/i2c-npcm7xx.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 31e3d2c9d6bc..c1b679737240 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2362,8 +2362,17 @@ static struct platform_driver npcm_i2c_bus_driver = {

static int __init npcm_i2c_init(void)
{
+ int ret;
+
npcm_i2c_debugfs_dir = debugfs_create_dir("npcm_i2c", NULL);
- return platform_driver_register(&npcm_i2c_bus_driver);
+
+ ret = platform_driver_register(&npcm_i2c_bus_driver);
+ if (ret) {
+ debugfs_remove_recursive(npcm_i2c_debugfs_dir);
+ return ret;
+ }
+
+ return 0;
}
module_init(npcm_i2c_init);

--
2.35.1