acct: replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.  This read may exceed the
destination size limit.  This is both inefficient and can lead to linear
read overflows if a source string is not NUL-terminated [1].  In an effort
to remove strlcpy() completely [2], replace strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Link: https://lkml.kernel.org/r/20230710011748.3538624-1-azeemshaikh38@gmail.com
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/acct.c b/kernel/acct.c
index 010667ce60801a498ffdcce39af2147f1028179c..10f769e13f724dd18615be9bfb2ec47dcabc7b1b 100644 (file)
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -445,7 +445,7 @@ static void fill_ac(acct_t *ac)
        memset(ac, 0, sizeof(acct_t));
 
        ac->ac_version = ACCT_VERSION | ACCT_BYTEORDER;
-       strlcpy(ac->ac_comm, current->comm, sizeof(ac->ac_comm));
+       strscpy(ac->ac_comm, current->comm, sizeof(ac->ac_comm));
 
        /* calculate run_time in nsec*/
        run_time = ktime_get_ns();