4.4-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 6637401c35b2f327a35d27f44bda05e327f2f017 ]
Every user of user_insn() passes an user memory pointer to this macro.
Add might_fault() to user_insn() so we can spot users which are using this macro in sections where page faulting is not allowed.
[ bp: Space it out to make it more visible. ]
Signed-off-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Signed-off-by: Borislav Petkov bp@suse.de Reviewed-by: Rik van Riel riel@surriel.com Cc: "H. Peter Anvin" hpa@zytor.com Cc: "Jason A. Donenfeld" Jason@zx2c4.com Cc: Andy Lutomirski luto@kernel.org Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Ingo Molnar mingo@redhat.com Cc: Jann Horn jannh@google.com Cc: Paolo Bonzini pbonzini@redhat.com Cc: Radim Krčmář rkrcmar@redhat.com Cc: Thomas Gleixner tglx@linutronix.de Cc: kvm ML kvm@vger.kernel.org Cc: x86-ml x86@kernel.org Link: https://lkml.kernel.org/r/20181128222035.2996-6-bigeasy@linutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/include/asm/fpu/internal.h | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 16825dda18dc..66a5e60f60c4 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -94,6 +94,9 @@ extern void fpstate_sanitize_xstate(struct fpu *fpu); #define user_insn(insn, output, input...) \ ({ \ int err; \ + \ + might_fault(); \ + \ asm volatile(ASM_STAC "\n" \ "1:" #insn "\n\t" \ "2: " ASM_CLAC "\n" \