Bug 470608 – sys-libs/uclibc[-nptl] and [-ssp]: stack_guard not initialized which crashes (at least) on i386 w/-fstack-protector

• Product: Gentoo Linux
• Status: RESOLVED OBSOLETE

[Description SpanKY 2013-05-19 06:49:47 UTC]

when you build uClibc with USE=-ssp, the stack_guard pointer is not initialized (left at 0).  on i386, gcc attempts to deref that pointer directly when you use the -fstack-protector flag:
00000000 <main>:
   0:   55                      push   %ebp
   1:   89 e5                   mov    %esp,%ebp
   3:   83 e4 f0                and    $0xfffffff0,%esp
   6:   83 ec 20                sub    $0x20,%esp
   9:   65 a1 14 00 00 00       mov    %gs:0x14,%eax

offset 0x14 in the thread mem area on i386 is the uintptr_t stack_guard.

uClibc will initialize that only when built with USE=ssp, and only with the newer nptl port (USE=nptl).  so if you're using USE=-nptl (linuxthreads) or USE=-ssp, this will cause crashes.

probably need to update the code to at least point the stack_guard to a dummy location when built w/USE=-ssp.

[Comment 1 Anthony Basile 2013-09-12 20:26:11 UTC]

*** Bug 267335 has been marked as a duplicate of this bug. ***

[Comment 2 Pacho Ramos 2018-10-08 12:01:17 UTC]

is this affecting uclibc-ng too?

[Comment 3 Anthony Basile 2018-10-13 09:10:07 UTC]

(In reply to Pacho Ramos from comment #2)
> is this affecting uclibc-ng too?

nope

[Comment 4 Pacho Ramos 2018-10-13 09:20:23 UTC]

Maybe this (and other similar bug reports) could be closed then :)

In my case I noticed this when reviewing bug 467306

[Comment 5 Anthony Basile 2018-10-14 12:04:33 UTC]

(In reply to Pacho Ramos from comment #4)
> Maybe this (and other similar bug reports) could be closed then :)
> 
> In my case I noticed this when reviewing bug 467306

sys-libs/uclibc has been removed from the tree, replaced by sys-libs/uclibc-ng