On Mon, Mar 23, 2015 at 01:37:38PM +1100, NeilBrown wrote: > lustre's ->follow_link() uses a lot of stack space and so > need to limit symlink recursion based on stack size. > > It currently tests current->link_count, but that will soon > become private to fs/namei.c. > So instead base on actual available stack space. > This patch aborts recursive symlinks in less than 2K of space > is available. This seems consistent with current code, but > hasn't been tested. BTW, in the best case that logics is fishy. We have "up to 5 levels with 4Kb stack and up to 7 with 8Kb one". Could somebody manage to dig out the reasons for such limits? Preferably along with the kernel version where the overflows had been observed, both for 4K and 8K cases. I'm very tempted to rip that thing out in the "kill link_path_walk() recursion completely" series... -- 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
