Replace kmalloc() followed by copy_from_user() with memdup_user_nul() to simplify and improve osnoise_cpus_write(). Remove the manual NUL-termination.
No functional changes intended. Signed-off-by: Thorsten Blum <[email protected]> --- Changes in v3: - Use memdup_user_nul() instead of memdup_user() because of the fix a2501032de0d ("tracing/osnoise: Fix slab-out-of-bounds in _parse_integer_limit()") - Link to v2: https://lore.kernel.org/lkml/[email protected]/ Changes in v2: - Rebase to apply to master and linux-next - Explicitly include linux/string.h - Link to v1: https://lore.kernel.org/lkml/[email protected]/ --- kernel/trace/trace_osnoise.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index dc734867f0fc..26d0c99125f5 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -24,6 +24,7 @@ #include <linux/sched/clock.h> #include <uapi/linux/sched/types.h> #include <linux/sched.h> +#include <linux/string.h> #include "trace.h" #ifdef CONFIG_X86_LOCAL_APIC @@ -2325,13 +2326,9 @@ osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count, if (count < 1) return 0; - buf = kmalloc(count + 1, GFP_KERNEL); - if (!buf) - return -ENOMEM; - - if (copy_from_user(buf, ubuf, count)) - return -EFAULT; - buf[count] = '\0'; + buf = memdup_user_nul(ubuf, count); + if (IS_ERR(buf)) + return PTR_ERR(buf); if (!zalloc_cpumask_var(&osnoise_cpumask_new, GFP_KERNEL)) return -ENOMEM; -- 2.51.0
