Re: [PATCH 1/2] mm: vmpressure: don't need call kfree if kstrndup fails

From: Yang Shi
Date: Wed Feb 12 2020 - 22:14:45 EST




On 2/12/20 3:21 AM, David Hildenbrand wrote:
On 11.02.20 06:24, Yang Shi wrote:
When kstrndup fails (returns NULL) there is no memory is allocated by
kmalloc, so no need to call kfree().
"When kstrndup fails, no memory was allocated and we can exit directly."

Thanks for correcting the commit log.

Andrew, do you prefer I send an updated version or you would just update the patch in -mm tree?


Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
---
mm/vmpressure.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 4bac22f..0590f00 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -371,10 +371,8 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
int ret = 0;
spec_orig = spec = kstrndup(args, MAX_VMPRESSURE_ARGS_LEN, GFP_KERNEL);
- if (!spec) {
- ret = -ENOMEM;
- goto out;
- }
+ if (!spec)
+ return -ENOMEM;
/* Find required level */
token = strsep(&spec, ",");