From: Teng Qi starmiku1207184332@gmail.com
[ Upstream commit 0fa68da72c3be09e06dd833258ee89c33374195f ]
The definition of macro MOTO_SROM_BUG is: #define MOTO_SROM_BUG (lp->active == 8 && (get_unaligned_le32( dev->dev_addr) & 0x00ffffff) == 0x3e0008)
and the if statement if (MOTO_SROM_BUG) lp->active = 0;
using this macro indicates lp->active could be 8. If lp->active is 8 and the second comparison of this macro is false. lp->active will remain 8 in: lp->phy[lp->active].gep = (*p ? p : NULL); p += (2 * (*p) + 1); lp->phy[lp->active].rst = (*p ? p : NULL); p += (2 * (*p) + 1); lp->phy[lp->active].mc = get_unaligned_le16(p); p += 2; lp->phy[lp->active].ana = get_unaligned_le16(p); p += 2; lp->phy[lp->active].fdx = get_unaligned_le16(p); p += 2; lp->phy[lp->active].ttm = get_unaligned_le16(p); p += 2; lp->phy[lp->active].mci = *p;
However, the length of array lp->phy is 8, so array overflows can occur. To fix these possible array overflows, we first check lp->active and then return -EINVAL if it is greater or equal to ARRAY_SIZE(lp->phy) (i.e. 8).
Reported-by: TOTE Robot oslab@tsinghua.edu.cn Signed-off-by: Teng Qi starmiku1207184332@gmail.com Reviewed-by: Arnd Bergmann arnd@arndb.de Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/dec/tulip/de4x5.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/net/ethernet/dec/tulip/de4x5.c b/drivers/net/ethernet/dec/tulip/de4x5.c index b39e8315e4e27..a5a291b848b06 100644 --- a/drivers/net/ethernet/dec/tulip/de4x5.c +++ b/drivers/net/ethernet/dec/tulip/de4x5.c @@ -4704,6 +4704,10 @@ type3_infoblock(struct net_device *dev, u_char count, u_char *p) lp->ibn = 3; lp->active = *p++; if (MOTO_SROM_BUG) lp->active = 0; + /* if (MOTO_SROM_BUG) statement indicates lp->active could + * be 8 (i.e. the size of array lp->phy) */ + if (WARN_ON(lp->active >= ARRAY_SIZE(lp->phy))) + return -EINVAL; lp->phy[lp->active].gep = (*p ? p : NULL); p += (2 * (*p) + 1); lp->phy[lp->active].rst = (*p ? p : NULL); p += (2 * (*p) + 1); lp->phy[lp->active].mc = get_unaligned_le16(p); p += 2;