Re: commit-message attack for extracting sensitive data from rewritten Git history

2013-04-09 Thread Roberto Tyley
On 9 April 2013 18:01, Jeff King wrote: > On Tue, Apr 09, 2013 at 08:03:24AM +0200, Johannes Sixt wrote: >> If A mentions B (think of cherry-pick -x), then you must ensure that the >> branch containing B was traversed first. > > Yeah, you're right. Multiple passes are necessary to get it > complet

Re: commit-message attack for extracting sensitive data from rewritten Git history

2013-04-09 Thread Jeff King
On Tue, Apr 09, 2013 at 08:03:24AM +0200, Johannes Sixt wrote: > Am 4/8/2013 23:54, schrieb Jeff King: > > Yeah, it would make sense for filter-branch to have a "--map-commit-ids" > > option or similar that does the update. At first I thought it might take > > two passes, but I don't think it is n

Re: commit-message attack for extracting sensitive data from rewritten Git history

2013-04-08 Thread Johannes Sixt
Am 4/8/2013 23:54, schrieb Jeff King: > Yeah, it would make sense for filter-branch to have a "--map-commit-ids" > option or similar that does the update. At first I thought it might take > two passes, but I don't think it is necessary, as long as we traverse > the commits topologically (i.e., you

Re: commit-message attack for extracting sensitive data from rewritten Git history

2013-04-08 Thread Jeff King
On Mon, Apr 08, 2013 at 08:40:36AM -0700, Junio C Hamano wrote: > With or without the security issue, leaving old object names that > will become irrelevant in the rewritten history will make the > resulting history less useful, simply because people cannot look at > the objects these messages ref

Re: commit-message attack for extracting sensitive data from rewritten Git history

2013-04-08 Thread Junio C Hamano
Roberto Tyley writes: > Here's an unmodified repo, in which the user unwisely committed a > database password: > > https://github.com/bfg-repo-cleaner-demos/gma-demo-repo-original/commit/8c9cfe3c > > The unwise commit is reverted with a second commit using 'git revert', > which obviously leaves t

commit-message attack for extracting sensitive data from rewritten Git history

2013-04-07 Thread Roberto Tyley
This is a demonstration of a mildly-interesting security concern relating to Git & git-filter-branch - not a vulnerability in Git itself, just in the way it can be used. I thought it was interesting to demonstrate that there is sometimes an avenue of attack for recovering sensitive data that's been