Re: [PATCH 1/1] ext4: fix crash on BUG_ON in ext4_alloc_group_tables

On 9/26/24 11:04 AM, Eric Sandeen wrote:

Can you explain what the 2 cases under

/* Avoid allocating large 'groups' array if not needed */

are doing? I *think* the first 'if' is trying not to over-allocate for the last batch of block groups that get added during a resize. What is the "else if" case doing?

(or maybe I had that backwards)

Incidentally, the offending commit that this fixes (665d3e0af4d35ac) got turned into CVE-2023-52622, so it's quite likely that distros have backported the broken commit as part of the CVE game.

So the followup fix looks a bit urgent to me.

-Eric