Re: [PATCH] Set hard limit on delta chain depth
- From
Nguyen Thai Ngoc Duy <pclouds@gmail.com>
- Date
- Dec 6, 2011, 12:32 UTC
- Message-ID
- <CACsJy8BuUn4htSR6jAJfbueOshE6-YVV5dZGSWTGXbkuA0HO=A@mail.gmail.com>
- In-Reply-To
- <CABPQNSaE=TWGbBRMnthEuT181=XbOafPfgx88_JQnnQ6TiYyqw@mail.gmail.com>
2011/12/6 Erik Faye-Lund <kusmabite@gmail.com>:
Show 18 quoted lines
> 2011/12/5 Nguyễn Thái Ngọc Duy <pclouds@gmail.com>: >> Too deep delta chains can cause stack overflow in get_base_data(). Set >> a hard limit so that index-pack does not run out of stack. Also stop >> people from producing such a long delta chains using "pack-object >> --depth=<too large>" >> >> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> >> --- >> I used to make very long delta chains and triggered this in index-pack. >> I did not care reporting because it's my fault anyway. Think again, >> index-pack is called at server side and a malicious client can >> trigger this. This patch does not improve the situation much, but at >> least we won't get sigsegv at server side. >> > > Wouldn't it make more sense to make the limit a config option rather > than a hard-coded value of 128 (which seems arbitrary to me)? After > all, different platforms have different stack-limitations...
Then it'd make more sense to make a compile time config based on platform. We could have a config option that can override the default, but I really don't see the point of making long delta chains.
-- Duy