RE: [PATCH] image: check if the file is core dump

["Schmidt, Adriaan" <adriaan.schmidt@siemens.com>]

Zhibin Dong, Dienstag, 16. April 2024 07:12
> 
> The previous code does a wrong judgement in two cases:
> 1. a file is suffixed by .core but is not a core dump file
> 2. a file is a core dump file but is not suffixed by .core
> 
> The new code uses `file` to determine the type of files, which is more
> accurate.
> 
> Signed-off-by: Zhibin Dong <zhibin.dong@siemens.com>
> ---
>  meta/classes/image.bbclass | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/meta/classes/image.bbclass b/meta/classes/image.bbclass
> index 98741da0..10923947 100644
> --- a/meta/classes/image.bbclass
> +++ b/meta/classes/image.bbclass
> @@ -444,7 +444,7 @@ EOSUDO
> 
>      # Sometimes qemu-user-static generates coredumps in chroot, move them
>      # to work temporary directory and inform user about it.
> -    for f in $(sudo find ${ROOTFSDIR} -type f -name *.core); do
> +    for f in $(sudo find ${ROOTFSDIR} -type f -exec file {} \; | grep 'core

This runs `file` on every file in the rootfs, which I expect can take a long time.

Also, if you check `file -l | grep core` you will see that not all file types
that have "core" in their description are actually core dumps.

I don't know the details of why we have this code [1], but maybe "scan the whole
rootfs" is not the best solution to the problem...

When specifically can those core dumps happen?
Is it only during update-initramfs, which is mentioned in the bug linked to the original commit [2]?
Maybe also during package installation, which may run commands with qemu-user?
Can we reproduce this?
Where in the rootfs are they stored?
Can our search for them be more targeted?
Would such core dumps be caught by other checks we have in place (e.g., modification time of files)?

Adriaan

[1] introduced in fa10b1d9b3a5e876bbcf556b03d585bf712fa7a5
[2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1040981

> file' | cut -d: -f1); do
>          sudo mv "${f}" "${WORKDIR}/temp/"
>          bbwarn "found core dump in rootfs, check it in
> ${WORKDIR}/temp/${f##*/}"
>      done
> --
> 2.39.2
> 
> --
> You received this message because you are subscribed to the Google Groups
> "isar-users" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to isar-users+unsubscribe@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/isar-users/20240416051222.3344127-1-
> zhibin.dong%40siemens.com.