[PATCH net 1/3] net: stmmac: replace memcpy with strscpy in ethtool
From: Konrad Leszczynski <hidden>
Date: 2025-08-28 09:57:55
Also in:
lkml
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds
Fix kernel exception by replacing memcpy with strscpy when used with
safety feature strings in ethtool logic.
[ +0.000023] BUG: KASAN: global-out-of-bounds in stmmac_get_strings+0x17d/0x520 [stmmac]
[ +0.000115] Read of size 32 at addr ffffffffc0cfab20 by task ethtool/2571
[ +0.000005] Call Trace:
[ +0.000004] <TASK>
[ +0.000003] dump_stack_lvl+0x6c/0x90
[ +0.000016] print_report+0xce/0x610
[ +0.000011] ? stmmac_get_strings+0x17d/0x520 [stmmac]
[ +0.000108] ? kasan_addr_to_slab+0xd/0xa0
[ +0.000008] ? stmmac_get_strings+0x17d/0x520 [stmmac]
[ +0.000101] kasan_report+0xd4/0x110
[ +0.000010] ? stmmac_get_strings+0x17d/0x520 [stmmac]
[ +0.000102] kasan_check_range+0x3a/0x1c0
[ +0.000010] __asan_memcpy+0x24/0x70
[ +0.000008] stmmac_get_strings+0x17d/0x520 [stmmac]
Fixes: 8bf993a5877e8a0a ("net: stmmac: Add support for DWMAC5 and implement Safety Features")
Reviewed-by: Sebastian Basierski <redacted>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Konrad Leszczynski <redacted>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
index 77758a7299b4..0433be4bd0c4 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c@@ -752,7 +752,7 @@ static void stmmac_get_strings(struct net_device *dev, u32 stringset, u8 *data) if (!stmmac_safety_feat_dump(priv, &priv->sstats, i, NULL, &desc)) { - memcpy(p, desc, ETH_GSTRING_LEN); + strscpy(p, desc, ETH_GSTRING_LEN); p += ETH_GSTRING_LEN; } }
--
2.34.1