cvs commit: src/sys/amd64/amd64 cpu_switch.S machdep.c src/sys/amd64/ia32 ia32_signal.c

[Konstantin Belousov]

kib         2008-09-02 17:52:11 UTC

  FreeBSD src repository

  Modified files:
    sys/amd64/amd64      cpu_switch.S machdep.c 
    sys/amd64/ia32       ia32_signal.c 
  Log:
  SVN rev 182684 on 2008-09-02 17:52:11Z by kib
  
  - When executing FreeBSD/amd64 binaries from FreeBSD/i386 or Linux/i386
    processes, clear PCB_32BIT and PCB_GS32BIT bits [1].
  
  - Reread the fs and gs bases from the msr unconditionally, not believing
    the values in pcb_fsbase and pcb_gsbase, since usermode may reload
    segment registers, invalidating the cache. [2].
  
  Both problems resulted in the wrong fs base, causing wrong tls pointer
  be dereferenced in the usermode.
  
  Reported and tested by: Vyacheslav Bocharov <adeepv at gmail com> [1]
  Reported by:    Bernd Walter <ticsoat cicely7 cicely de>,
          Artem Belevich <fbsdlist at src cx>[2]
  Reviewed by:    peter
  MFC after:      3 days
  
  Revision  Changes    Path
  1.163     +18 -2     src/sys/amd64/amd64/cpu_switch.S
  1.688     +1 -0      src/sys/amd64/amd64/machdep.c
  1.19      +1 -0      src/sys/amd64/ia32/ia32_signal.c