From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELsmV02nMicEBEoFHUVDRN+kVEDmI6rD1gADAtUjzGBH/S9btsVse58s7UiOqHif6um95LIr ARC-Seal: i=1; a=rsa-sha256; t=1521484194; cv=none; d=google.com; s=arc-20160816; b=SJ8vmsh63TcMRZbxdmU5JqwqRUt+WgHKfR1S3C5kpn/z9AXJCHnh3Xc/qLZb0xpS/o /gsiCELMrF0adzmhGtLD/ujLMvRvli0ro96yQnnp9135lvPlwB/+wXGA/rocCuPLYCdI gpWbqiEOUs9zx+8eyyfhlvAI4ZJ0itfglB108FGSbR8CL+lL9WPey9QlXJZrODbp+qWu fP3AFEAbcxSQ8iuOiKWSN2R93Gr3g9koSg2GuZnv8VH+cooyvdUByon/oEkoaEvYKP3y iHBwOm73XbjxBg5BYpzRIMJ/cuxcz/yuVJG08/pj5wxzTk5ct9HlNUxTe0w3oumUeFO5 BM6Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=lBku0SqG12lubuO6dSkePKP3iAHMrgPawGBkrF1Idn0=; b=t4ntbUO9fIQu1Kg7Nx7wLqqyp3uXqknlgTJPIq4CDBaXm/OfSxAG0w2w5ulkZgOEJ8 vdKHqB/mnyM2eziimPaUGhRvbMQ+JvCg/OZ1kU2WW57hlMUM0R6iOy9HtfvOzNfBU+4M FRaIz+nVaSYrFpD76x48d/PcnNNi4CUJ3lmACc5DOUlbJG5HjlNrT0qxKfx+Gxgl1ek9 KpE9vPeff7MmkeI011SkieGdgjT1veReytZ2NGKPj/7BbG8FsLI2FTprZnKLB8SkCorn nKeX2MoshudBfZdT0vULaugVguu05W3Kfd5HZwDPkntJoWhZiENESJjZYFP4UK/GIMgF FzzQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bart Oldeman , Andy Lutomirski , Borislav Petkov , Brian Gerst , Denys Vlasenko , "H. Peter Anvin" , Josh Poimboeuf , Linus Torvalds , Peter Zijlstra , Stas Sergeev , Thomas Gleixner , Ingo Molnar Subject: [PATCH 4.14 06/41] selftests/x86/entry_from_vm86: Add test cases for POPF Date: Mon, 19 Mar 2018 19:08:06 +0100 Message-Id: <20180319180732.612954571@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180319180732.195217948@linuxfoundation.org> References: <20180319180732.195217948@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1595391056075291570?= X-GMAIL-MSGID: =?utf-8?q?1595391811093798231?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski commit 78393fdde2a456cafa414b171c90f26a3df98b20 upstream. POPF is currently broken -- add tests to catch the error. This results in: [RUN] POPF with VIP set and IF clear from vm86 mode [INFO] Exited vm86 mode due to STI [FAIL] Incorrect return reason (started at eip = 0xd, ended at eip = 0xf) because POPF currently fails to check IF before reporting a pending interrupt. This patch also makes the FAIL message a bit more informative. Reported-by: Bart Oldeman Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stas Sergeev Cc: Thomas Gleixner Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/a16270b5cfe7832d6d00c479d0f871066cbdb52b.1521003603.git.luto@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/x86/entry_from_vm86.c | 30 +++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) --- a/tools/testing/selftests/x86/entry_from_vm86.c +++ b/tools/testing/selftests/x86/entry_from_vm86.c @@ -95,6 +95,10 @@ asm ( "int3\n\t" "vmcode_int80:\n\t" "int $0x80\n\t" + "vmcode_popf_hlt:\n\t" + "push %ax\n\t" + "popf\n\t" + "hlt\n\t" "vmcode_umip:\n\t" /* addressing via displacements */ "smsw (2052)\n\t" @@ -124,8 +128,8 @@ asm ( extern unsigned char vmcode[], end_vmcode[]; extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[], - vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[], - vmcode_umip_str[], vmcode_umip_sldt[]; + vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_popf_hlt[], + vmcode_umip[], vmcode_umip_str[], vmcode_umip_sldt[]; /* Returns false if the test was skipped. */ static bool do_test(struct vm86plus_struct *v86, unsigned long eip, @@ -175,7 +179,7 @@ static bool do_test(struct vm86plus_stru (VM86_TYPE(ret) == rettype && VM86_ARG(ret) == retarg)) { printf("[OK]\tReturned correctly\n"); } else { - printf("[FAIL]\tIncorrect return reason\n"); + printf("[FAIL]\tIncorrect return reason (started at eip = 0x%lx, ended at eip = 0x%lx)\n", eip, v86->regs.eip); nerrs++; } @@ -264,6 +268,9 @@ int main(void) v86.regs.ds = load_addr / 16; v86.regs.es = load_addr / 16; + /* Use the end of the page as our stack. */ + v86.regs.esp = 4096; + assert((v86.regs.cs & 3) == 0); /* Looks like RPL = 0 */ /* #BR -- should deliver SIG??? */ @@ -295,6 +302,23 @@ int main(void) v86.regs.eflags &= ~X86_EFLAGS_IF; do_test(&v86, vmcode_sti - vmcode, VM86_STI, 0, "STI with VIP set"); + /* POPF with VIP set but IF clear: should not trap */ + v86.regs.eflags = X86_EFLAGS_VIP; + v86.regs.eax = 0; + do_test(&v86, vmcode_popf_hlt - vmcode, VM86_UNKNOWN, 0, "POPF with VIP set and IF clear"); + + /* POPF with VIP set and IF set: should trap */ + v86.regs.eflags = X86_EFLAGS_VIP; + v86.regs.eax = X86_EFLAGS_IF; + do_test(&v86, vmcode_popf_hlt - vmcode, VM86_STI, 0, "POPF with VIP and IF set"); + + /* POPF with VIP clear and IF set: should not trap */ + v86.regs.eflags = 0; + v86.regs.eax = X86_EFLAGS_IF; + do_test(&v86, vmcode_popf_hlt - vmcode, VM86_UNKNOWN, 0, "POPF with VIP clear and IF set"); + + v86.regs.eflags = 0; + /* INT3 -- should cause #BP */ do_test(&v86, vmcode_int3 - vmcode, VM86_TRAP, 3, "INT3");