[PATCH v2] counter: fix an IS_ERR() vs NULL bug

From: Dan Carpenter
Date: Tue Jan 11 2022 - 12:35:15 EST


There are 8 callers for devm_counter_alloc() and they all check for NULL
instead of error pointers. I think NULL is the better thing to return
for allocation functions so update counter_alloc() and devm_counter_alloc()
to return NULL instead of error pointers.

Fixes: c18e2760308e ("counter: Provide alternative counter registration functions")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
v2: make additional style changes

drivers/counter/counter-core.c | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
index 7e0957eea094..869894b74741 100644
--- a/drivers/counter/counter-core.c
+++ b/drivers/counter/counter-core.c
@@ -90,10 +90,8 @@ struct counter_device *counter_alloc(size_t sizeof_priv)
int err;

ch = kzalloc(sizeof(*ch) + sizeof_priv, GFP_KERNEL);
- if (!ch) {
- err = -ENOMEM;
- goto err_alloc_ch;
- }
+ if (!ch)
+ return NULL;

counter = &ch->counter;
dev = &counter->dev;
@@ -123,9 +121,8 @@ struct counter_device *counter_alloc(size_t sizeof_priv)
err_ida_alloc:

kfree(ch);
-err_alloc_ch:

- return ERR_PTR(err);
+ return NULL;
}
EXPORT_SYMBOL_GPL(counter_alloc);

@@ -208,12 +205,12 @@ struct counter_device *devm_counter_alloc(struct device *dev, size_t sizeof_priv
int err;

counter = counter_alloc(sizeof_priv);
- if (IS_ERR(counter))
- return counter;
+ if (!counter)
+ return NULL;

err = devm_add_action_or_reset(dev, devm_counter_put, counter);
if (err < 0)
- return ERR_PTR(err);
+ return NULL;

return counter;
}
--
2.20.1