Re: [FD] Anomaly in Fedora `dnf update`: md5 mismatch of result

[Adrean Boyadzhiev]

Probably a completely different root cause, but I have noticed similar behavior with a Debian-based distribution during `# apt upgrade` and when there are many packages for update and the internet connection is not so good. I haven't investigated, but my assumptions were either Race Conditions within verification logic or some logic related to the timestamp.

Also, isn't md5 deprecated and known to suck much?

Best regards,

--
Adrean Boyadzhiev
https://lambdabit.io


On 8/14/23 14:43, Georgi Guninski wrote:

To my knowledge `md5` should be ok for calculating hash sums, many prefer it since the algorithm is relatively fast and simple.

In short, I found anomaly in Fedora 37 and would like to
know if it is vulnerability.

As root type in terminal:
dnf update

If there is kernel update, watch stdout and stderr for:

##On Mon Aug 14 05:33:29 AM UTC 2023
(2/6): kernel-6.4.10-100.fc37.x86_64.rpm        1.2 MB/s | 140 kB     00:00
/var/cache/dnf/updates-fd4d3d0d1c34d49a/packages/kernel-modules-extra-6.4.9-100.fc37_6.4.10-100.fc37.x86_64.drpm:
md5 mismatch of result

##$ md5sum 
/var/cache/dnf/updates-fd4d3d0d1c34d49a/packages/kernel-modules-extra-6.4.9-100.fc37_6.4.10-100.fc37.x86_64.drpm
356ea04e06bd58db4a15c64e64432f1a
/var/cache/dnf/updates-fd4d3d0d1c34d49a/packages/kernel-modules-extra-6.4.9-100.fc37_6.4.10-100.fc37.x86_64.drpm

Another possible approach:  install  Fedora 37 in VM without internet
access and then do `dnf update` (haven't tested this yet).

After second download, the kernel update passes, but I don't
understand why the second download via http://mirror should pass.

Examining the dnf source is option.

Open problem:  Can this be vulnerability, possibly assuming
hostile mirror or network?

Also, isn't md5 deprecated and known to suck much?

OpenPGP_0xC5FFCE15F846C301.asc
Description: OpenPGP public key

OpenPGP_signature.asc
Description: OpenPGP digital signature

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