[PATCH v2 0/2] Convert copy_from_user() + kstrtouint() to kstrtouint_from_user()

From: Fushuai Wang

Date: Sat Jan 17 2026 - 09:57:00 EST


From: Fushuai Wang <wangfushuai@xxxxxxxxx>

Hi,

There are several places use copy_from_user() to copy a string from
userspase, followed by kstrtoXXX() to convert it to a desired type.
This approach requires manually handling NUL-termination and proper
buffer sizing, which is error-prone and unnecessarily complex. The
kernel provides kstrtoXXX_from_user() helpers to copy a string from
userspace and perform the conversion in one step. So use a
kstrtoXXX_from_user() instead of copy_from_user() + kstrtoXXX().

Recent discussion:
https://lore.kernel.org/all/20260112073039.1185-1-fushuai.wang@xxxxxxxxx/T/

v1:
https://lore.kernel.org/all/20260116131751.45768-1-fushuai.wang@xxxxxxxxx/T/#t

Fushuai Wang (2):
sched/debug: Convert copy_from_user() + kstrtouint() to
kstrtouint_from_user()
x86/tlb: Convert copy_from_user() + kstrtouint() to
kstrtouint_from_user()

arch/x86/mm/tlb.c | 13 ++++---------
kernel/sched/debug.c | 14 ++++----------
2 files changed, 8 insertions(+), 19 deletions(-)

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2.36.1