On Wed, Sep 14, 2011 at 01:14:38PM +0200, Pavel Machek wrote: > Hi! > ... > > > > Pavel, I somehow lost. What exactly the security issue here? There are a few > > patches from Vasiliy in -mm queue at moment. In particular one includes > > .permission set for fd/ handling. So I've updated the map_files as well > > (it's below). So please review and point me where the problem > > is. Thanks! > > AFAICT, this recreates existing problem with /proc/<pid>/fd (see > discussion at > > http://www.securityfocus.com/archive/1/507386/30/0/threaded > > ). It creates object that looks like symlink, but does not behave as > one, and permissions of directories are not checked as they would be > if it was a symlink. > > Pavel OK, so the problem is that we might return a path to the file mapped even if the directory which consists the former file has its permission changed, right? For example, lets say we have | lr-x------ 1 cyrill cyrill 64 Sep 14 19:35 /proc/self/map_files/3d73a00000-3d73a1c000 -> /lib64/ld-2.5.so and once /lib64 became unreadable we should not return the path to 3d73a00000-3d73a1c000 as well, that is what you mean, right? Cyrill -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
