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| author | Keir Fraser <keir.fraser@citrix.com> | 2008-03-19 14:06:18 +0000 |
|---|---|---|
| committer | Keir Fraser <keir.fraser@citrix.com> | 2008-03-19 14:06:18 +0000 |
| commit | 7065b5e4c16be241d7182cd4fcbd316c4b14e3de (patch) | |
| tree | 05a7b3755c2a5491f07b3a15ab4ab2133030dfb6 /xen/arch/x86/x86_emulate.c | |
| parent | f966bc9fc5e1f1ea04f0d7ddddc0f8e8733f3139 (diff) | |
| download | xen-7065b5e4c16be241d7182cd4fcbd316c4b14e3de.tar.gz xen-7065b5e4c16be241d7182cd4fcbd316c4b14e3de.tar.bz2 xen-7065b5e4c16be241d7182cd4fcbd316c4b14e3de.zip | |
x86_emulate: Return X86EMUL_UNHANDLEABLE if mode_iopl() or
mode_ring0() checks cannot be carried out.
Also fix handling of EFLAGS.IF in iret and popf.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
Diffstat (limited to 'xen/arch/x86/x86_emulate.c')
| -rw-r--r-- | xen/arch/x86/x86_emulate.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/xen/arch/x86/x86_emulate.c b/xen/arch/x86/x86_emulate.c index b3bb4deb52..6981f9b52d 100644 --- a/xen/arch/x86/x86_emulate.c +++ b/xen/arch/x86/x86_emulate.c @@ -785,11 +785,21 @@ _mode_iopl( struct x86_emulate_ops *ops) { int cpl = get_cpl(ctxt, ops); + if ( cpl == -1 ) + return -1; return ((cpl >= 0) && (cpl <= ((ctxt->regs->eflags >> 12) & 3))); } -#define mode_ring0() (get_cpl(ctxt, ops) == 0) -#define mode_iopl() _mode_iopl(ctxt, ops) +#define mode_ring0() ({ \ + int _cpl = get_cpl(ctxt, ops); \ + fail_if(_cpl < 0); \ + (_cpl == 0); \ +}) +#define mode_iopl() ({ \ + int _iopl = _mode_iopl(ctxt, ops); \ + fail_if(_iopl < 0); \ + _iopl; \ +}) static int in_realmode( @@ -2394,8 +2404,10 @@ x86_emulate( case 0x9d: /* popf */ { uint32_t mask = EFLG_VIP | EFLG_VIF | EFLG_VM; - if ( !mode_iopl() ) + if ( !mode_ring0() ) mask |= EFLG_IOPL; + if ( !mode_iopl() ) + mask |= EFLG_IF; /* 64-bit mode: POP defaults to a 64-bit operand. */ if ( mode_64bit() && (op_bytes == 4) ) op_bytes = 8; @@ -2640,8 +2652,10 @@ x86_emulate( case 0xcf: /* iret */ { unsigned long cs, eip, eflags; uint32_t mask = EFLG_VIP | EFLG_VIF | EFLG_VM; - if ( !mode_iopl() ) + if ( !mode_ring0() ) mask |= EFLG_IOPL; + if ( !mode_iopl() ) + mask |= EFLG_IF; fail_if(!in_realmode(ctxt, ops)); if ( (rc = ops->read(x86_seg_ss, sp_post_inc(op_bytes), &eip, op_bytes, ctxt)) || |