[Qemu-devel] [PATCH] usb: fix unbound stack warning for inotify_watchfn

[Qemu-devel] [PATCH] usb: fix unbound stack warning for inotify_watchfn

[Peter Xu]

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/usb/dev-mtp.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c
index 7391783..76ad64e 100644
--- a/hw/usb/dev-mtp.c
+++ b/hw/usb/dev-mtp.c
@@ -433,12 +433,11 @@ static void inotify_watchfn(void *arg)
     MTPState *s = arg;
     ssize_t bytes;
     /* From the man page: atleast one event can be read */
-    int len = sizeof(struct inotify_event) + NAME_MAX + 1;
     int pos;
-    char buf[len];
+    char buf[sizeof(struct inotify_event) + NAME_MAX + 1];
 
     for (;;) {
-        bytes = read(s->inotifyfd, buf, len);
+        bytes = read(s->inotifyfd, buf, sizeof(buf));
         pos = 0;
 
         if (bytes <= 0) {
-- 
2.4.3

Re: [Qemu-devel] [PATCH] usb: fix unbound stack warning for inotify_watchfn

[Paolo Bonzini]

On 09/03/2016 07:07, Peter Xu wrote:
> -    char buf[len];
> +    char buf[sizeof(struct inotify_event) + NAME_MAX + 1];
>  
>      for (;;) {
> -        bytes = read(s->inotifyfd, buf, len);
> +        bytes = read(s->inotifyfd, buf, sizeof(buf));

sizeof is good here, since read takes a size in bytes.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

Re: [Qemu-devel] [PATCH] usb: fix unbound stack warning for inotify_watchfn

[Gerd Hoffmann]

On Mi, 2016-03-09 at 14:07 +0800, Peter Xu wrote:
> Signed-off-by: Peter Xu <peterx@redhat.com>

added to usb queue.

thanks,
  Gerd