On Mon, May 15, 2017 at 03:09:33PM -0400, Nikolai Lifanov wrote: > On 05/15/2017 14:52, Alexey Dokuchaev wrote: > > Does it mean that old Linux' trick of /lib/ld-linux.so.2 /bin/chmod +x > > /bin/chmod would now be possible on FreeBSD as well? Does this have > > any security implications? > > This is a use case for fixing accidentally hosed /bin/chmod binary and > not some sort of an escalation thing. You will need to be root to do > this.
Because /bin/chmod is owned by root, not because /libexec/ld-elf.so.1 is limiting execution to root only, or is it (I might have missed uid check in that patch [1], but at a quick glance I didn't see it). On a living system, there are plenty of other ways to restore missing +x on /bin/chmod as long as you can call chmod(2), from simple Python script down to manually crafting small binary in hex. > Likewise, with working chmod binary, you should be able to mark > binaries with write access executable. Well, it's not just about chmod(1), this opens what can be a can of worms and I want to know how big it is. ./danfe [1] Idea for security.bsd.ld_elf_exec_root_only sysctl(8)? _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
