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-rw-r--r--main/xen/xsa202-4.6.patch73
1 files changed, 0 insertions, 73 deletions
diff --git a/main/xen/xsa202-4.6.patch b/main/xen/xsa202-4.6.patch
deleted file mode 100644
index 0c7fff0e34..0000000000
--- a/main/xen/xsa202-4.6.patch
+++ /dev/null
@@ -1,73 +0,0 @@
-From: Jan Beulich <jbeulich@suse.com>
-Subject: x86: force EFLAGS.IF on when exiting to PV guests
-
-Guest kernels modifying instructions in the process of being emulated
-for another of their vCPU-s may effect EFLAGS.IF to be cleared upon
-next exiting to guest context, by converting the being emulated
-instruction to CLI (at the right point in time). Prevent any such bad
-effects by always forcing EFLAGS.IF on. And to cover hypothetical other
-similar issues, also force EFLAGS.{IOPL,NT,VM} to zero.
-
-This is XSA-202.
-
-Signed-off-by: Jan Beulich <jbeulich@suse.com>
-
---- a/xen/arch/x86/x86_64/compat/entry.S
-+++ b/xen/arch/x86/x86_64/compat/entry.S
-@@ -174,6 +174,8 @@ compat_bad_hypercall:
- /* %rbx: struct vcpu, interrupts disabled */
- ENTRY(compat_restore_all_guest)
- ASSERT_INTERRUPTS_DISABLED
-+ mov $~(X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_VM),%r11d
-+ and UREGS_eflags(%rsp),%r11d
- .Lcr4_orig:
- .skip .Lcr4_alt_end - .Lcr4_alt, 0x90
- .Lcr4_orig_end:
-@@ -209,6 +211,8 @@ ENTRY(compat_restore_all_guest)
- (.Lcr4_orig_end - .Lcr4_orig), \
- (.Lcr4_alt_end - .Lcr4_alt)
- .popsection
-+ or $X86_EFLAGS_IF,%r11
-+ mov %r11d,UREGS_eflags(%rsp)
- RESTORE_ALL adj=8 compat=1
- .Lft0: iretq
-
---- a/xen/arch/x86/x86_64/entry.S
-+++ b/xen/arch/x86/x86_64/entry.S
-@@ -40,28 +40,29 @@ restore_all_guest:
- testw $TRAP_syscall,4(%rsp)
- jz iret_exit_to_guest
-
-+ movq 24(%rsp),%r11 # RFLAGS
-+ andq $~(X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_VM),%r11
-+ orq $X86_EFLAGS_IF,%r11
-+
- /* Don't use SYSRET path if the return address is not canonical. */
- movq 8(%rsp),%rcx
- sarq $47,%rcx
- incl %ecx
- cmpl $1,%ecx
-- ja .Lforce_iret
-+ movq 8(%rsp),%rcx # RIP
-+ ja iret_exit_to_guest
-
- cmpw $FLAT_USER_CS32,16(%rsp)# CS
-- movq 8(%rsp),%rcx # RIP
-- movq 24(%rsp),%r11 # RFLAGS
- movq 32(%rsp),%rsp # RSP
- je 1f
- sysretq
- 1: sysretl
-
--.Lforce_iret:
-- /* Mimic SYSRET behavior. */
-- movq 8(%rsp),%rcx # RIP
-- movq 24(%rsp),%r11 # RFLAGS
- ALIGN
- /* No special register assumptions. */
- iret_exit_to_guest:
-+ andl $~(X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_VM),24(%rsp)
-+ orl $X86_EFLAGS_IF,24(%rsp)
- addq $8,%rsp
- .Lft0: iretq
-