[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] [PULL 23/25] pcnet: fix possible buffer overflow

From: Jason Wang
Subject: [Qemu-devel] [PULL 23/25] pcnet: fix possible buffer overflow
Date: Wed, 26 Sep 2018 11:16:48 +0800

In pcnet_receive(), we try to assign size_ to size which converts from
size_t to integer. This will cause troubles when size_ is greater
INT_MAX, this will lead a negative value in size and it can then pass
the check of size < MIN_BUF_SIZE which may lead out of bound access
for both buf and buf1.

Fixing by converting the type of size to size_t.

CC: address@hidden
Reported-by: Daniel Shapira <address@hidden>
Reviewed-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Jason Wang <address@hidden>
 hw/net/pcnet.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/net/pcnet.c b/hw/net/pcnet.c
index 0c44554168..d9ba04bdfc 100644
--- a/hw/net/pcnet.c
+++ b/hw/net/pcnet.c
@@ -988,14 +988,14 @@ ssize_t pcnet_receive(NetClientState *nc, const uint8_t 
*buf, size_t size_)
     uint8_t buf1[60];
     int remaining;
     int crc_err = 0;
-    int size = size_;
+    size_t size = size_;
     if (CSR_DRX(s) || CSR_STOP(s) || CSR_SPND(s) || !size ||
         (CSR_LOOP(s) && !s->looptest)) {
         return -1;
-    printf("pcnet_receive size=%d\n", size);
+    printf("pcnet_receive size=%zu\n", size);
     /* if too small buffer, then expand it */

reply via email to

[Prev in Thread] Current Thread [Next in Thread]