From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELswZJFUtON2PMMKh6zhawEQcJ0KiVGlUcrqbC3Kk/yJMmwQAFEabAFycToPMtKn1lYWelQZ ARC-Seal: i=1; a=rsa-sha256; t=1521484074; cv=none; d=google.com; s=arc-20160816; b=n97Yx7mc0hAQO7ei1pqtvv3AznOi17+xfjH9jaHkpvaaxJGJFH2uB5oIcgbUUB7M3b rCRqZ+D70d1AYst771uXHcHgnNotTYSMfz3/Ip3jUgdn6l7I8L1mi9TQrvGsczYQkrNl BL4qlzdcKHp4jvCv+UwMbpAWCrrl3po7+994S+8BP6T8sem/rigZKK7p1MrTdDbjkRk0 syZ2CqlozAxR+xghD6/PRb811Pjp+DHnKgxJD7wNOEAZJT+DlBCrdHEWQioMOA4WkX6F +cHnyudnkponUV/C9u6gOpLeD7xhdTTP+9lYNyRQR28Ew0bvW8Qpgnxy4wAYjUGzs7jA 6eAw== 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=SthghpMiWly7xM2X8eHIExbvuwV244ZLRaMzJWXs+T8=; b=yO56PV/nyipwDJIZkOa/Qm7HMgk/DNpjEJGeZWAw0Q9RZzzzz1L5rCn2YWfM4IAgC2 oBgcmLH3vDin00GpvODXmiqC1u0ZnyVua3LCKvZGoKRQTS2zB7KzEAG6c+1EuKbUMcdO AVtqFgScIRDOo6kUQqfq10/RRAW+/VcJB5ER/F8cdZI7v9h9AieGcZSNBiMWx7oFbkKW WfznnKdeIRRLYUukJFjkZUCO8aCG2nMY2jNtIceMvEBzB0gOtj33EkqfnvNESt0mf7am 2qIH2MhUQwc0XbYU62PtLY3claQC4hO7ZLA5OqN4B8lY1eO04tQmhRlpm9ysw1Z4c5N/ 3gDw== 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, Ricardo Neri , Thomas Gleixner , Andrew Morton , Andy Lutomirski , Borislav Petkov , Borislav Petkov , Brian Gerst , Chen Yucong , Chris Metcalf , Dave Hansen , Denys Vlasenko , Fenghua Yu , "H. Peter Anvin" , Huang Rui , Jiri Slaby , Jonathan Corbet , Josh Poimboeuf , Linus Torvalds , Masami Hiramatsu , "Michael S. Tsirkin" , Paolo Bonzini , Paul Gortmaker , Peter Zijlstra , "Ravi V. Shankar" , Shuah Khan , Tony Luck , Vlastimil Babka , ricardo.neri@intel.com, Ingo Molnar Subject: [PATCH 4.9 215/241] selftests/x86: Add tests for the STR and SLDT instructions Date: Mon, 19 Mar 2018 19:08:00 +0100 Message-Id: <20180319180800.075419133@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180319180751.172155436@linuxfoundation.org> References: <20180319180751.172155436@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?1595391053287071016?= X-GMAIL-MSGID: =?utf-8?q?1595391685248500889?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ricardo Neri commit a9e017d5619eb371460c8e516f4684def62bef3a upstream. The STR and SLDT instructions are not valid when running on virtual-8086 mode and generate an invalid operand exception. These two instructions are protected by the Intel User-Mode Instruction Prevention (UMIP) security feature. In protected mode, if UMIP is enabled, these instructions generate a general protection fault if called from CPL > 0. Linux traps the general protection fault and emulates the instructions sgdt, sidt and smsw; but not str and sldt. These tests are added to verify that the emulation code does not emulate these two instructions but the expected invalid operand exception is seen. Tests fallback to exit with INT3 in case emulation does happen. Signed-off-by: Ricardo Neri Reviewed-by: Thomas Gleixner Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Chen Yucong Cc: Chris Metcalf Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Huang Rui Cc: Jiri Slaby Cc: Jonathan Corbet Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Ravi V. Shankar Cc: Shuah Khan Cc: Tony Luck Cc: Vlastimil Babka Cc: ricardo.neri@intel.com Link: http://lkml.kernel.org/r/1509935277-22138-13-git-send-email-ricardo.neri-calderon@linux.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/x86/entry_from_vm86.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) --- a/tools/testing/selftests/x86/entry_from_vm86.c +++ b/tools/testing/selftests/x86/entry_from_vm86.c @@ -111,6 +111,11 @@ asm ( "smsw %ax\n\t" "mov %ax, (2080)\n\t" "int3\n\t" + "vmcode_umip_str:\n\t" + "str %eax\n\t" + "vmcode_umip_sldt:\n\t" + "sldt %eax\n\t" + "int3\n\t" ".size vmcode, . - vmcode\n\t" "end_vmcode:\n\t" ".code32\n\t" @@ -119,7 +124,8 @@ 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_sti[], vmcode_int3[], vmcode_int80[], 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, @@ -226,6 +232,16 @@ void do_umip_tests(struct vm86plus_struc printf("[FAIL]\tAll the results of SIDT should be the same.\n"); else printf("[PASS]\tAll the results from SIDT are identical.\n"); + + sethandler(SIGILL, sighandler, 0); + do_test(vm86, vmcode_umip_str - vmcode, VM86_SIGNAL, 0, + "STR instruction"); + clearhandler(SIGILL); + + sethandler(SIGILL, sighandler, 0); + do_test(vm86, vmcode_umip_sldt - vmcode, VM86_SIGNAL, 0, + "SLDT instruction"); + clearhandler(SIGILL); } int main(void)