git am cannot parse the mbox when PGP signatures are present

[jgunthorpe]

Here is an example from the kernel mailing list:

https://patchwork.kernel.org/patch/10656215/mbox/

The original mbox is attached to this issue.

Patchwork removed all the MIME encoding and signature but retained the Content-Type header saying it is in multipart/signed format.

'git am' knows how to parse this header and gets confused when the mailbox is no longer in the right format.

patchworks should also drop the content-type header if it is going to do this kind of reformatting.

orig.mbox.gz

[stephenfin]

@jgunthorpe This is likely introduced by 01b9cbb. Previously, this header would not have been copied in as we restricted the possible headers one could use. Is there any particular reason to include the signature in the downloaded mbox? If not, I'm inclined to think the correct behavior here would be to special case Content-Type: multipart/signed (or Content-Type in general) and strip this out.

[jgunthorpe]

I don't think git am can currently validate the gpg signature so I don't think there is any reason to provide it at this time. Stripping/rewriting content-type, content-length and content-encoding is probably the right thing to do if the body is being rewritten.

[andy-shev]

Should be reopened since this broke non-manual application of the patch. If you don't supply a signature the Content type of the mbox has to be mangled accordingly.

Patch to test with: https://patchwork.kernel.org/patch/10921937/

[jgunthorpe]

I think this is the same breakage reported here.. It kind of looks like the patch may not understand the extended Content-type header being used here:

Content-Type: multipart/signed; micalg=pgp-sha1;
        protocol="application/pgp-signature"; boundary="EeQfGwPcQSOJBaQU"

[andy-shev]

Actually git am the tool which fails. patch works nicely on this. I tried to download a mailbox via git pw and pwclient with the same result. I think either both tools are broken, or patchwork itself.