[Qemu-devel] [PATCH] usb-redir: fix stack overflow in usbredir_log_data

[Qemu-devel] [PATCH] usb-redir: fix stack overflow in usbredir_log_data

[Gerd Hoffmann]

Don't reinvent a broken wheel, just use the hexdump function we have.

Impact: low, broken code doesn't run unless you have debug logging
enabled.

Reported-by: 李强 <liqiang6-s@360.cn>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/usb/redirect.c | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
index b001a27f05..ad5ef783a6 100644
--- a/hw/usb/redirect.c
+++ b/hw/usb/redirect.c
@@ -229,21 +229,10 @@ static void usbredir_log(void *priv, int level, const char *msg)
 static void usbredir_log_data(USBRedirDevice *dev, const char *desc,
     const uint8_t *data, int len)
 {
-    int i, j, n;
-
     if (dev->debug < usbredirparser_debug_data) {
         return;
     }
-
-    for (i = 0; i < len; i += j) {
-        char buf[128];
-
-        n = sprintf(buf, "%s", desc);
-        for (j = 0; j < 8 && i + j < len; j++) {
-            n += sprintf(buf + n, " %02X", data[i + j]);
-        }
-        error_report("%s", buf);
-    }
+    qemu_hexdump((char *)data, stderr, desc, len);
 }
 
 /*
-- 
2.9.3

Re: [Qemu-devel] [PATCH] usb-redir: fix stack overflow in usbredir_log_data

[Manos Pitsidianakis]

Shouldn't we be checking if a monitor has been set instead of printing 
to stderr anyway?

On Tue, May 09, 2017 at 01:01:28PM +0200, Gerd Hoffmann wrote:
>Don't reinvent a broken wheel, just use the hexdump function we have.
>
>Impact: low, broken code doesn't run unless you have debug logging
>enabled.
>
>Reported-by: 李强 <liqiang6-s@360.cn>
>Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
>---
> hw/usb/redirect.c | 13 +------------
> 1 file changed, 1 insertion(+), 12 deletions(-)
>
>diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
>index b001a27f05..ad5ef783a6 100644
>--- a/hw/usb/redirect.c
>+++ b/hw/usb/redirect.c
>@@ -229,21 +229,10 @@ static void usbredir_log(void *priv, int level, const char *msg)
> static void usbredir_log_data(USBRedirDevice *dev, const char *desc,
>     const uint8_t *data, int len)
> {
>-    int i, j, n;
>-
>     if (dev->debug < usbredirparser_debug_data) {
>         return;
>     }
>-
>-    for (i = 0; i < len; i += j) {
>-        char buf[128];
>-
>-        n = sprintf(buf, "%s", desc);
>-        for (j = 0; j < 8 && i + j < len; j++) {
>-            n += sprintf(buf + n, " %02X", data[i + j]);
>-        }
>-        error_report("%s", buf);
>-    }
>+    qemu_hexdump((char *)data, stderr, desc, len);
> }
>
> /*
>-- 
>2.9.3
>
>
>