x86: Don't leak 64-bit kernel register values to 32-bit processes

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While 32-bit processes can't directly access R8...R15, they can
gain access to these registers by temporarily switching themselves
into 64-bit mode.

Therefore, registers not preserved anyway by called C functions
(i.e. R8...R11) must be cleared prior to returning to user mode.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: <stable@kernel.org>
LKML-Reference: <4AC34D73020000780001744A@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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Jan Beulich 2009-09-30 11:22:11 +01:00 • committed by Ingo Molnar

parent 4701472e44

commit 24e35800cd

1 changed files with 23 additions and 13 deletions

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arch/x86/ia32/ia32entry.S

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