memcpy: detected field-spanning write (size 8) of single field "le->name"

memcpy: detected field-spanning write (size 8) of single field "le->name"

[Mike Kazantsev]

Hi,

Running latest stable linux kernels, I seem to have this WARNING pop-up
under specific "create/write multiple 1-2M files per second" workload
on ntfs3 mountpoint (generated by aria2c downloader for youtube DASH
videos via yt-dlp):

  memcpy: detected field-spanning write (size 8) of single field
  "le->name" at fs/ntfs3/attrlist.c:326 (size 6)

I think this is a warning from security/sanity checks introduced in 6.x
at some point, and might not be an actual problem that breaks anything.

But presumably warnings still shouldn't be emitted, and fix might to
split the write in two, if it's intentionally overwriting the next
field as well, or mark it in the code as a non-issue somehow.

I've initially reported it at https://bugzilla.kernel.org/show_bug.cgi?id=217937
but it was suggested there to post it to this mailing list instead.
See couple backtraces (which seem to be rather easily reproducible) attached there.

Didn't look into the issue myself, but thought to report it anyway,
in case it might be useful, and maybe trivial to fix.

Cheers!


-- 
Mike Kazantsev // fraggod.net