strncpy() is deprecated [1] for NUL-terminated destination buffers since it does not guarantee NUL termination. Replace it with strscpy_pad() to ensure NUL termination of the destination buffer while retaining the NUL-padding behavior of strncpy(). Even though the identifier buffer has 252 usable bytes, strncpy() intentionally copied only 251 bytes into the zero-initialized buffer, implicitly relying on the last byte to act as the terminator. Switching to strscpy_pad() removes the need for this trick and avoids using magic numbers. The source string is also NUL-terminated and satisfies the __must_be_cstr() requirement of strscpy_pad(). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Signed-off-by: Thorsten Blum --- net/ipv4/ipconfig.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 22a7889876c1..27cc6f8070b7 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -1690,7 +1690,8 @@ static int __init ic_proto_name(char *name) *v = 0; if (kstrtou8(client_id, 0, dhcp_client_identifier)) pr_debug("DHCP: Invalid client identifier type\n"); - strncpy(dhcp_client_identifier + 1, v + 1, 251); + strscpy_pad(dhcp_client_identifier + 1, v + 1, + sizeof(dhcp_client_identifier) - 1); *v = ','; } return 1; -- Thorsten Blum GPG: 1D60 735E 8AEF 3BE4 73B6 9D84 7336 78FD 8DFE EAD4