From 473f8f2d1bfe1103f20140fdc80cad406b4d68c0 Mon Sep 17 00:00:00 2001 From: Justin Stitt Date: Tue, 10 Oct 2023 21:38:11 +0000 Subject: [PATCH] octeontx2-af: replace deprecated strncpy with strscpy `strncpy` is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. We can see that linfo->lmac_type is expected to be NUL-terminated based on the `... - 1`'s present in the current code. Presumably making room for a NUL-byte at the end of the buffer. Considering the above, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer without unnecessarily NUL-padding. Let's also prefer the more idiomatic strscpy usage of (dest, src, sizeof(dest)) rather than (dest, src, SOME_LEN). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20231010-strncpy-drivers-net-ethernet-marvell-octeontx2-af-cgx-c-v1-1-a443e18f9de8@google.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/marvell/octeontx2/af/cgx.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c index e06f77ad6106b..6c70c84986904 100644 --- a/drivers/net/ethernet/marvell/octeontx2/af/cgx.c +++ b/drivers/net/ethernet/marvell/octeontx2/af/cgx.c @@ -1218,8 +1218,6 @@ static inline void link_status_user_format(u64 lstat, struct cgx_link_user_info *linfo, struct cgx *cgx, u8 lmac_id) { - const char *lmac_string; - linfo->link_up = FIELD_GET(RESP_LINKSTAT_UP, lstat); linfo->full_duplex = FIELD_GET(RESP_LINKSTAT_FDUPLEX, lstat); linfo->speed = cgx_speed_mbps[FIELD_GET(RESP_LINKSTAT_SPEED, lstat)]; @@ -1230,12 +1228,12 @@ static inline void link_status_user_format(u64 lstat, if (linfo->lmac_type_id >= LMAC_MODE_MAX) { dev_err(&cgx->pdev->dev, "Unknown lmac_type_id %d reported by firmware on cgx port%d:%d", linfo->lmac_type_id, cgx->cgx_id, lmac_id); - strncpy(linfo->lmac_type, "Unknown", LMACTYPE_STR_LEN - 1); + strscpy(linfo->lmac_type, "Unknown", sizeof(linfo->lmac_type)); return; } - lmac_string = cgx_lmactype_string[linfo->lmac_type_id]; - strncpy(linfo->lmac_type, lmac_string, LMACTYPE_STR_LEN - 1); + strscpy(linfo->lmac_type, cgx_lmactype_string[linfo->lmac_type_id], + sizeof(linfo->lmac_type)); } /* Hardware event handlers */