When building with -Warray-bounds, the following warning is emitted:
In file included from ./include/linux/string.h:253,
from ./arch/x86/include/asm/page_32.h:22,
from ./arch/x86/include/asm/page.h:14,
from ./arch/x86/include/asm/thread_info.h:12,
from ./include/linux/thread_info.h:60,
from ./arch/x86/include/asm/preempt.h:7,
from ./include/linux/preempt.h:78,
from ./include/linux/rcupdate.h:27,
from ./include/linux/rculist.h:11,
from ./include/linux/sched/signal.h:5,
from ./drivers/staging/rtl8723bs/include/drv_types.h:17,
from drivers/staging/rtl8723bs/core/rtw_recv.c:7:
In function 'memcpy',
inlined from 'wlanhdr_to_ethhdr' at drivers/staging/rtl8723bs/core/rtw_recv.c:1554:2:
./include/linux/fortify-string.h:41:33: warning: '__builtin_memcpy' offset [0, 5] is out of the bounds [0, 0] [-Warray-bounds]
41 | #define __underlying_memcpy __builtin_memcpy
| ^
This is because the compiler sees it is possible for "ptr" to be a NULL
value, and concludes that it has zero size and attempts to copy to it
would overflow. Instead, remove the get_recvframe_data() entirely, as
it's not possible for this to ever be NULL.
Additionally add missing NULL checks after recvframe_pull() (which are
present in the rtl8712 driver).
Cc: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Cc: Phillip Potter <phil@xxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Michael Straube <straube.linux@xxxxxxxxx>
Cc: Fabio Aiuto <fabioaiuto83@xxxxxxxxx>
Cc: linux-staging@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/staging/r8188eu/core/rtw_recv.c | 6 +++++-
drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c | 4 +---
drivers/staging/r8188eu/include/rtw_recv.h | 9 ---------
3 files changed, 6 insertions(+), 13 deletions(-)
diff --git a/drivers/staging/r8188eu/core/rtw_recv.c b/drivers/staging/r8188eu/core/rtw_recv.c
index 51a13262a226..946e659ae97a 100644
--- a/drivers/staging/r8188eu/core/rtw_recv.c
+++ b/drivers/staging/r8188eu/core/rtw_recv.c
@@ -1188,7 +1188,7 @@ static int wlanhdr_to_ethhdr(struct recv_frame *precvframe)
struct adapter *adapter = precvframe->adapter;
struct mlme_priv *pmlmepriv = &adapter->mlmepriv;
- u8 *ptr = get_recvframe_data(precvframe); /* point to frame_ctrl field */
+ u8 *ptr = precvframe->rx_data; /* point to frame_ctrl field */
struct rx_pkt_attrib *pattrib = &precvframe->attrib;
if (pattrib->encrypt)
@@ -1223,10 +1223,14 @@ static int wlanhdr_to_ethhdr(struct recv_frame *precvframe)
eth_type = 0x8712;
/* append rx status for mp test packets */
ptr = recvframe_pull(precvframe, (rmv_len - sizeof(struct ethhdr) + 2) - 24);
+ if (!ptr)
+ return _FAIL;
memcpy(ptr, get_rxmem(precvframe), 24);
ptr += 24;
} else {
ptr = recvframe_pull(precvframe, (rmv_len - sizeof(struct ethhdr) + (bsnaphdr ? 2 : 0)));
+ if (!ptr)
+ return _FAIL;
}
memcpy(ptr, pattrib->dst, ETH_ALEN);
diff --git a/drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c b/drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c
index 90d426199f52..bf93ff3af140 100644
--- a/drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c
+++ b/drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c
@@ -128,7 +128,7 @@ void update_recvframe_phyinfo_88e(struct recv_frame *precvframe, struct phy_stat
struct rx_pkt_attrib *pattrib = &precvframe->attrib;
struct hal_data_8188e *pHalData = &padapter->haldata;
struct phy_info *pPHYInfo = &pattrib->phy_info;
- u8 *wlanhdr;
+ u8 *wlanhdr = precvframe->rx_data;
struct odm_per_pkt_info pkt_info;
u8 *sa = NULL;
struct sta_priv *pstapriv;
@@ -138,8 +138,6 @@ void update_recvframe_phyinfo_88e(struct recv_frame *precvframe, struct phy_stat
pkt_info.bPacketToSelf = false;
pkt_info.bPacketBeacon = false;
- wlanhdr = get_recvframe_data(precvframe);
-
pkt_info.bPacketMatchBSSID = ((!IsFrameTypeCtrl(wlanhdr)) &&
!pattrib->icv_err && !pattrib->crc_err &&
!memcmp(get_hdr_bssid(wlanhdr),
diff --git a/drivers/staging/r8188eu/include/rtw_recv.h b/drivers/staging/r8188eu/include/rtw_recv.h
index b43a46887343..920f33235e00 100644
--- a/drivers/staging/r8188eu/include/rtw_recv.h
+++ b/drivers/staging/r8188eu/include/rtw_recv.h
@@ -296,15 +296,6 @@ static inline u8 *get_rx_status(struct recv_frame *precvframe)
return get_rxmem(precvframe);
}
-static inline u8 *get_recvframe_data(struct recv_frame *precvframe)
-{
- /* always return rx_data */
- if (precvframe == NULL)
- return NULL;
-
- return precvframe->rx_data;
-}
-
static inline u8 *recvframe_push(struct recv_frame *precvframe, int sz)
{
/* append data before rx_data */
--
2.30.2
