forwarded 382746 http://gcc.gnu.org/PR29231 tags 382746 + upstream thanks
Albert, please could you consider subscribing to the upstram report? Albert Cahalan writes: > Package: gcc-4.1 > Version: 4.1.1-5 > Severity: important > > __trampoline_setup in /lib/libgcc_s.so.1 puts code on the stack. > > This contributes to insecurity on powerpc. > > A half-way fix is to mmap a page for this evil crud. > This still violates good practice, needing the OS to > allow either write+execute or a dangerous transition > from write to execute. It'd be an improvement though. > Doing write+execute may be better, allowing the OS > to locate the page within a segment (256 MiB chunk > on PowerPC) which already has executable pages. > > A better method would be to supply a page full of > trampoline functions in libgcc. Each function would: > > 1. examine its own address > 2. map from the page of code to a page of data > 3. use that data to implement the trampoline > > Trampoline setup would thus involve filling in the > data and choosing the matching function to use. > > Once libgcc stops putting code on the stack, gcc > needs to mark all executables as not requiring an > executable stack. > > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
