[PATCH 4.4 53/57] r8169: Avoid memcpy() over-reading of ETH_SS_STATS

From: Sasha Levin
Date: Mon Jun 28 2021 - 11:29:22 EST


From: Kees Cook <keescook@xxxxxxxxxxxx>

[ Upstream commit da5ac772cfe2a03058b0accfac03fad60c46c24d ]

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading across neighboring array fields.

The memcpy() is copying the entire structure, not just the first array.
Adjust the source argument so the compiler can do appropriate bounds
checking.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/realtek/r8169.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index f3a685d3f649..55b0f11bf2a0 100644
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -2314,7 +2314,7 @@ static void rtl8169_get_strings(struct net_device *dev, u32 stringset, u8 *data)
{
switch(stringset) {
case ETH_SS_STATS:
- memcpy(data, *rtl8169_gstrings, sizeof(rtl8169_gstrings));
+ memcpy(data, rtl8169_gstrings, sizeof(rtl8169_gstrings));
break;
}
}
--
2.30.2