Patchwork [V3,5/7] block: Add infinite loop check in drive_init()

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Submitter Xu Wang
Date July 15, 2013, 9:42 a.m.
Message ID <1373881356-3294-6-git-send-email-cngesaint@gmail.com>
Download mbox | patch
Permalink /patch/258974/
State New
Headers show

Comments

Xu Wang - July 15, 2013, 9:42 a.m.
Backing file should be checked if there is a loop in it during image
boot. Becase if there is loop qemu would no response for a long time
and segment fault occured. So this patch would check backing file
chain if there is loop in it before open image.

Signed-off-by: Xu Wang <cngesaint@gmail.com>
---
 blockdev.c | 6 ++++++
 1 file changed, 6 insertions(+)
Fam Zheng - July 18, 2013, 5:27 a.m.
On Mon, 07/15 05:42, Xu Wang wrote:
> Backing file should be checked if there is a loop in it during image
> boot. Becase if there is loop qemu would no response for a long time
> and segment fault occured. So this patch would check backing file
> chain if there is loop in it before open image.
> 
> Signed-off-by: Xu Wang <cngesaint@gmail.com>
> ---
>  blockdev.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/blockdev.c b/blockdev.c
> index b3a57e0..b5f063f 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -695,6 +695,12 @@ DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type)
>          error_report("warning: disabling copy_on_read on readonly drive");
>      }
>  
> +    /* Add backing file loop check */
> +    if (bdrv_backing_file_loop_check(file, drv ? drv->format_name : NULL,
> +                                     NULL, NULL)) {

Would you add an error_report here, as other error paths do?

> +        goto err;
> +    }
> +
>      ret = bdrv_open(dinfo->bdrv, file, bs_opts, bdrv_flags, drv);
>      bs_opts = NULL;
>  
> -- 
> 1.8.1.4
>

Patch

diff --git a/blockdev.c b/blockdev.c
index b3a57e0..b5f063f 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -695,6 +695,12 @@  DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type)
         error_report("warning: disabling copy_on_read on readonly drive");
     }
 
+    /* Add backing file loop check */
+    if (bdrv_backing_file_loop_check(file, drv ? drv->format_name : NULL,
+                                     NULL, NULL)) {
+        goto err;
+    }
+
     ret = bdrv_open(dinfo->bdrv, file, bs_opts, bdrv_flags, drv);
     bs_opts = NULL;