diff options
| author | Mario Preksavec <mario@slackware.hr> | 2016-03-31 22:20:20 +0200 |
|---|---|---|
| committer | Robby Workman <rworkman@slackbuilds.org> | 2016-04-03 02:33:04 -0500 |
| commit | 50cf57ce56b4877aca6148cd3de5efb13157cea9 (patch) | |
| tree | dbd3a9c1c903b266b9ac216cdba631a785ac87ff /system/xen/patches | |
| parent | 7859671412ce6e2cbe91dfd00657f675e44dca07 (diff) | |
| download | slackbuilds-50cf57ce56b4877aca6148cd3de5efb13157cea9.tar.gz | |
system/xen: Updated for kernel 4.4.6 and fixes.
Signed-off-by: Mario Preksavec <mario@slackware.hr>
Diffstat (limited to 'system/xen/patches')
| -rw-r--r-- | system/xen/patches/xsa172.patch | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/system/xen/patches/xsa172.patch b/system/xen/patches/xsa172.patch new file mode 100644 index 0000000000..8b1d01fa84 --- /dev/null +++ b/system/xen/patches/xsa172.patch @@ -0,0 +1,39 @@ +x86: fix information leak on AMD CPUs + +The fix for XSA-52 was wrong, and so was the change synchronizing that +new behavior to the FXRSTOR logic: AMD's manuals explictly state that +writes to the ES bit are ignored, and it instead gets calculated from +the exception and mask bits (it gets set whenever there is an unmasked +exception, and cleared otherwise). Hence we need to follow that model +in our workaround. + +This is XSA-172. + +The first hunk (xen/arch/x86/i387.c:fpu_fxrstor) is CVE-2016-3159. +The second hunk (xen/arch/x86/xstate.c:xrstor) is CVE-2016-3158. + +Signed-off-by: Jan Beulich <jbeulich@suse.com> +Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> + +--- a/xen/arch/x86/i387.c ++++ b/xen/arch/x86/i387.c +@@ -49,7 +49,7 @@ static inline void fpu_fxrstor(struct vc + * sometimes new user value. Both should be ok. Use the FPU saved + * data block as a safe address because it should be in L1. + */ +- if ( !(fpu_ctxt->fsw & 0x0080) && ++ if ( !(fpu_ctxt->fsw & ~fpu_ctxt->fcw & 0x003f) && + boot_cpu_data.x86_vendor == X86_VENDOR_AMD ) + { + asm volatile ( "fnclex\n\t" +--- a/xen/arch/x86/xstate.c ++++ b/xen/arch/x86/xstate.c +@@ -344,7 +344,7 @@ void xrstor(struct vcpu *v, uint64_t mas + * data block as a safe address because it should be in L1. + */ + if ( (mask & ptr->xsave_hdr.xstate_bv & XSTATE_FP) && +- !(ptr->fpu_sse.fsw & 0x0080) && ++ !(ptr->fpu_sse.fsw & ~ptr->fpu_sse.fcw & 0x003f) && + boot_cpu_data.x86_vendor == X86_VENDOR_AMD ) + asm volatile ( "fnclex\n\t" /* clear exceptions */ + "ffree %%st(7)\n\t" /* clear stack tag */ |