]> git.kernelconcepts.de Git - karo-tx-linux.git/commit
[PATCH] Add more prevent_tail_call()
authorOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Wed, 19 Apr 2006 23:59:40 +0000 (23:59 +0000)
committerGreg Kroah-Hartman <gregkh@suse.de>
Mon, 24 Apr 2006 16:56:05 +0000 (09:56 -0700)
commit7517f43bef6016c58c007446f882ecf98a5e287b
tree3705be76c3312c2da069e62fefea198d26f31cb8
parentccc182530680032711743be0e5533e6117e30139
[PATCH] Add more prevent_tail_call()

Those also break userland regs like following.

   00000000 <sys_chown16>:
      0: 0f b7 44 24 0c        movzwl 0xc(%esp),%eax
      5: 83 ca ff              or     $0xffffffff,%edx
      8: 0f b7 4c 24 08        movzwl 0x8(%esp),%ecx
      d: 66 83 f8 ff           cmp    $0xffffffff,%ax
     11: 0f 44 c2              cmove  %edx,%eax
     14: 66 83 f9 ff           cmp    $0xffffffff,%cx
     18: 0f 45 d1              cmovne %ecx,%edx
     1b: 89 44 24 0c           mov    %eax,0xc(%esp)
     1f: 89 54 24 08           mov    %edx,0x8(%esp)
     23: e9 fc ff ff ff        jmp    24 <sys_chown16+0x24>

where the tailcall at the end overwrites the incoming stack-frame.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
kernel/uid16.c