Hi Miquel, Am Mittwoch, 17. Juli 2024, 10:06:35 CEST schrieb 'Miquel Raynal' via upstream: > Hi Richard, > > [email protected] wrote on Fri, 12 Jul 2024 10:23:44 +0200: > > > The squashfs driver blindly follows symlinks, and calls sqfs_size() > > recursively. So an attacker can create a crafted filesystem and with > > a deep enough nesting level a stack overflow can be achieved. > > > > Fix by limiting the nesting level to 8. > > As this is I believe an arbitrary value, could we define this value > somewhere and flag it with a comment as "arbitrary" with some details > from the commit log? Right now the value '8' is hardcoded at least in 3 > different places.
I stole the value from the ext4 code. Since U-Boot lacks a common filesystem code, there will be always duplication. I can happily add a common define for the value. > Also, 8 seems rather small, any reason for choosing > that? I believe this is easy to cross even in non-evil filesystems and > could perhaps be (again, arbitrarily) increased a bit? For ext4 the value seems okay. So dunno. :-) Thanks, //richard -- sigma star gmbh | Eduard-Bodem-Gasse 6, 6020 Innsbruck, AUT UID/VAT Nr: ATU 66964118 | FN: 374287y
