Libguestfs - May 2013 - Re: [PATCH] inspection: handle empty file in parse_suse_release

If /etc/SuSE-release is empty then lines[0] is NULL, which is passed to
strdup. As a result virt-inspector will segfault.
This was introduced in commit 763ec36cf0c6ffa6d359b65ff7f1ee9ab1c7361e.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 src/inspect-fs-unix.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/inspect-fs-unix.c b/src/inspect-fs-unix.c
index 5fabaa2..c7d52c4 100644
--- a/src/inspect-fs-unix.c
+++ b/src/inspect-fs-unix.c
@@ -339,6 +339,8 @@ parse_suse_release (guestfs_h *g, struct inspect_fs *fs,
const char *filename)
     return -1;
 
   /* First line is dist release name */
+  if (lines[0] == NULL)
+    goto out;
   fs->product_name = safe_strdup (g, lines[0]);
   if (fs->product_name == NULL)
     goto out;

On Fri, May 31, 2013 at 01:38:31AM +0200, Olaf Hering
wrote:
> If /etc/SuSE-release is empty then lines[0] is NULL, which is passed to
> strdup. As a result virt-inspector will segfault.
> This was introduced in commit 763ec36cf0c6ffa6d359b65ff7f1ee9ab1c7361e.
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>
> ---
>  src/inspect-fs-unix.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/src/inspect-fs-unix.c b/src/inspect-fs-unix.c
> index 5fabaa2..c7d52c4 100644
> --- a/src/inspect-fs-unix.c
> +++ b/src/inspect-fs-unix.c
> @@ -339,6 +339,8 @@ parse_suse_release (guestfs_h *g, struct inspect_fs
*fs, const char *filename)
>      return -1;
>  
>    /* First line is dist release name */
> +  if (lines[0] == NULL)
> +    goto out;
>    fs->product_name = safe_strdup (g, lines[0]);
>    if (fs->product_name == NULL)
>      goto out;
This isn't complete because safe_strdup cannot return NULL.

Rich.

-- 
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On Fri, May 31, Richard W.M. Jones wrote:
> On Fri, May 31, 2013 at 01:38:31AM +0200, Olaf Hering wrote:
> > If /etc/SuSE-release is empty then lines[0] is NULL, which is passed
to
> > strdup. As a result virt-inspector will segfault.
> > This was introduced in commit
763ec36cf0c6ffa6d359b65ff7f1ee9ab1c7361e.
> > 
> > Signed-off-by: Olaf Hering <olaf@aepfle.de>
> > ---
> >  src/inspect-fs-unix.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/src/inspect-fs-unix.c b/src/inspect-fs-unix.c
> > index 5fabaa2..c7d52c4 100644
> > --- a/src/inspect-fs-unix.c
> > +++ b/src/inspect-fs-unix.c
> > @@ -339,6 +339,8 @@ parse_suse_release (guestfs_h *g, struct
inspect_fs *fs, const char *filename)
> >      return -1;
> >  
> >    /* First line is dist release name */
> > +  if (lines[0] == NULL)
> > +    goto out;
> >    fs->product_name = safe_strdup (g, lines[0]);
> >    if (fs->product_name == NULL)
> >      goto out;
> 
> This isn't complete because safe_strdup cannot return NULL.
Ok, the other change looks good. Thanks.


Olaf