Replace kmalloc() followed by copy_from_user() with memdup_user_nul() to
improve and simplify debug_get_user_string(). Remove the manual
NUL-termination.
No functional changes intended.
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
---
arch/s390/kernel/debug.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index c62100dc62c8..6a26f202441d 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -1416,18 +1416,12 @@ static inline char *debug_get_user_string(const char __user *user_buf,
{
char *buffer;
- buffer = kmalloc(user_len + 1, GFP_KERNEL);
- if (!buffer)
- return ERR_PTR(-ENOMEM);
- if (copy_from_user(buffer, user_buf, user_len) != 0) {
- kfree(buffer);
- return ERR_PTR(-EFAULT);
- }
+ buffer = memdup_user_nul(user_buf, user_len);
+ if (IS_ERR(buffer))
+ return buffer;
/* got the string, now strip linefeed. */
if (buffer[user_len - 1] == '\n')
buffer[user_len - 1] = 0;
- else
- buffer[user_len] = 0;
return buffer;
}
--
2.51.0
