Patchwork [1/1] image_types.bbclass: add --numeric-owner option to tar command

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Submitter Qi.Chen@windriver.com
Date Oct. 18, 2013, 7:47 a.m.
Message ID <83310635c381d335c132da1665c5568515dff386.1382082297.git.Qi.Chen@windriver.com>
Download mbox | patch
Permalink /patch/60205/
State New
Headers show

Comments

Qi.Chen@windriver.com - Oct. 18, 2013, 7:47 a.m.
From: Chen Qi <qi.chen@windriver.com>

If the same username exists on both target and the build host, but
the uids differ, and we start target via NFS, then the uid for the
user will be incorrect on target.

For example, if postfix's uid on host is 119 and on target is 1024,
then if we start target via NFS, the uid for postfix will be 119.

The root cause is that when we use runqemu-extract-sdk to generate
the NFS rootfs for later use, the tar command will respect the username
instead of uid. So if PSEUDO_PASSWD environment is not set correctly,
the host /etc/passwd will be used, resulting in wrong uids.

The situation for gid is completely analogous to that of uid.

It's almost impossible for the runqemu-extract-sdk to guess the correct
location of the needed password file merely based on the target tarball
name.

This patch solves this problem by adding the '--numeric-owner' option
to the tar command so that the username/groupname is not recorded in
the tarball. In this situation, we'll always get the correct uid/gid
after extracting the tarball.

[YOCTO #5364]

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
 meta/classes/image_types.bbclass |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
Richard Purdie - Oct. 18, 2013, 2:57 p.m.
On Fri, 2013-10-18 at 15:47 +0800, Qi.Chen@windriver.com wrote:
> From: Chen Qi <qi.chen@windriver.com>
> 
> If the same username exists on both target and the build host, but
> the uids differ, and we start target via NFS, then the uid for the
> user will be incorrect on target.
> 
> For example, if postfix's uid on host is 119 and on target is 1024,
> then if we start target via NFS, the uid for postfix will be 119.
> 
> The root cause is that when we use runqemu-extract-sdk to generate
> the NFS rootfs for later use, the tar command will respect the username
> instead of uid. So if PSEUDO_PASSWD environment is not set correctly,
> the host /etc/passwd will be used, resulting in wrong uids.
> 
> The situation for gid is completely analogous to that of uid.
> 
> It's almost impossible for the runqemu-extract-sdk to guess the correct
> location of the needed password file merely based on the target tarball
> name.
> 
> This patch solves this problem by adding the '--numeric-owner' option
> to the tar command so that the username/groupname is not recorded in
> the tarball. In this situation, we'll always get the correct uid/gid
> after extracting the tarball.
> 
> [YOCTO #5364]
> 
> Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
> ---
>  meta/classes/image_types.bbclass |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Er, isn't the right fix to fix runqemu-extract-sdk to use numeric IDs
then rather than butcher all the tarballs we create?

Cheers,

Richard
Qi.Chen@windriver.com - Oct. 21, 2013, 2:43 a.m.
On 10/18/2013 10:57 PM, Richard Purdie wrote:
> On Fri, 2013-10-18 at 15:47 +0800, Qi.Chen@windriver.com wrote:
>> From: Chen Qi <qi.chen@windriver.com>
>>
>> If the same username exists on both target and the build host, but
>> the uids differ, and we start target via NFS, then the uid for the
>> user will be incorrect on target.
>>
>> For example, if postfix's uid on host is 119 and on target is 1024,
>> then if we start target via NFS, the uid for postfix will be 119.
>>
>> The root cause is that when we use runqemu-extract-sdk to generate
>> the NFS rootfs for later use, the tar command will respect the username
>> instead of uid. So if PSEUDO_PASSWD environment is not set correctly,
>> the host /etc/passwd will be used, resulting in wrong uids.
>>
>> The situation for gid is completely analogous to that of uid.
>>
>> It's almost impossible for the runqemu-extract-sdk to guess the correct
>> location of the needed password file merely based on the target tarball
>> name.
>>
>> This patch solves this problem by adding the '--numeric-owner' option
>> to the tar command so that the username/groupname is not recorded in
>> the tarball. In this situation, we'll always get the correct uid/gid
>> after extracting the tarball.
>>
>> [YOCTO #5364]
>>
>> Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
>> ---
>>   meta/classes/image_types.bbclass |    2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
> Er, isn't the right fix to fix runqemu-extract-sdk to use numeric IDs
> then rather than butcher all the tarballs we create?
>
> Cheers,
>
> Richard
>
>
>

Thanks for pointing it out.
V2 has been sent out.

Best Regards,
Chen Qi

Patch

diff --git a/meta/classes/image_types.bbclass b/meta/classes/image_types.bbclass
index 9ead059..234c9ff 100644
--- a/meta/classes/image_types.bbclass
+++ b/meta/classes/image_types.bbclass
@@ -171,7 +171,7 @@  IMAGE_CMD_btrfs () {
 
 IMAGE_CMD_squashfs = "mksquashfs ${IMAGE_ROOTFS} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.squashfs ${EXTRA_IMAGECMD} -noappend"
 IMAGE_CMD_squashfs-xz = "mksquashfs ${IMAGE_ROOTFS} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.squashfs-xz ${EXTRA_IMAGECMD} -noappend -comp xz"
-IMAGE_CMD_tar = "cd ${IMAGE_ROOTFS} && tar -cvf ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.tar ."
+IMAGE_CMD_tar = "cd ${IMAGE_ROOTFS} && tar --numeric-owner -cvf ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.tar ."
 
 CPIO_TOUCH_INIT () {
 	if [ ! -L ${IMAGE_ROOTFS}/init ]