From b038c58bd258522d9cde6619d730ebdb1f7be198 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 30 Aug 2017 15:33:49 -0700 Subject: torture: Provide TMPDIR environment variable to specify tmpdir Both rcutorture and locktorture currently place temporary files in /tmp, in keeping with decades-long tradition. However, sometimes it is useful to specify an alternative temporary directory, for example, for space or performance reasons. This commit therefore causes the torture-test scripting to use the path specified in the TMPDIR environment variable, or to fall back to traditional /tmp if this variable is not set. Signed-off-by: Paul E. McKenney --- tools/testing/selftests/rcutorture/bin/config_override.sh | 2 +- tools/testing/selftests/rcutorture/bin/configcheck.sh | 2 +- tools/testing/selftests/rcutorture/bin/configinit.sh | 2 +- tools/testing/selftests/rcutorture/bin/kvm-build.sh | 2 +- tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh | 2 +- tools/testing/selftests/rcutorture/bin/kvm.sh | 4 ++-- tools/testing/selftests/rcutorture/bin/parse-build.sh | 2 +- tools/testing/selftests/rcutorture/bin/parse-torture.sh | 2 +- 8 files changed, 9 insertions(+), 9 deletions(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/rcutorture/bin/config_override.sh b/tools/testing/selftests/rcutorture/bin/config_override.sh index 49fa51726ce3..ef7fcbac3d42 100755 --- a/tools/testing/selftests/rcutorture/bin/config_override.sh +++ b/tools/testing/selftests/rcutorture/bin/config_override.sh @@ -42,7 +42,7 @@ else exit 1 fi -T=/tmp/config_override.sh.$$ +T=${TMPDIR-/tmp}/config_override.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/configcheck.sh b/tools/testing/selftests/rcutorture/bin/configcheck.sh index 70fca318a82b..197deece7c7c 100755 --- a/tools/testing/selftests/rcutorture/bin/configcheck.sh +++ b/tools/testing/selftests/rcutorture/bin/configcheck.sh @@ -19,7 +19,7 @@ # # Authors: Paul E. McKenney -T=/tmp/abat-chk-config.sh.$$ +T=${TMPDIR-/tmp}/abat-chk-config.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/configinit.sh b/tools/testing/selftests/rcutorture/bin/configinit.sh index 3f81a1095206..51f66a7ce876 100755 --- a/tools/testing/selftests/rcutorture/bin/configinit.sh +++ b/tools/testing/selftests/rcutorture/bin/configinit.sh @@ -32,7 +32,7 @@ # # Authors: Paul E. McKenney -T=/tmp/configinit.sh.$$ +T=${TMPDIR-/tmp}/configinit.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/kvm-build.sh b/tools/testing/selftests/rcutorture/bin/kvm-build.sh index 46752c164676..fb66d0173638 100755 --- a/tools/testing/selftests/rcutorture/bin/kvm-build.sh +++ b/tools/testing/selftests/rcutorture/bin/kvm-build.sh @@ -35,7 +35,7 @@ then exit 1 fi -T=/tmp/test-linux.sh.$$ +T=${TMPDIR-/tmp}/test-linux.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh index 0af36a721b9c..ab14b97c942c 100755 --- a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh +++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh @@ -38,7 +38,7 @@ # # Authors: Paul E. McKenney -T=/tmp/kvm-test-1-run.sh.$$ +T=${TMPDIR-/tmp}/kvm-test-1-run.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh index b55895fb10ed..ccd49e958fd2 100755 --- a/tools/testing/selftests/rcutorture/bin/kvm.sh +++ b/tools/testing/selftests/rcutorture/bin/kvm.sh @@ -30,7 +30,7 @@ scriptname=$0 args="$*" -T=/tmp/kvm.sh.$$ +T=${TMPDIR-/tmp}/kvm.sh.$$ trap 'rm -rf $T' 0 mkdir $T @@ -222,7 +222,7 @@ do exit 1 fi done -sort -k2nr $T/cfgcpu > $T/cfgcpu.sort +sort -k2nr $T/cfgcpu -T="$T" > $T/cfgcpu.sort # Use a greedy bin-packing algorithm, sorting the list accordingly. awk < $T/cfgcpu.sort > $T/cfgcpu.pack -v ncpus=$cpus ' diff --git a/tools/testing/selftests/rcutorture/bin/parse-build.sh b/tools/testing/selftests/rcutorture/bin/parse-build.sh index a6b57622c2e5..24fe5f822b28 100755 --- a/tools/testing/selftests/rcutorture/bin/parse-build.sh +++ b/tools/testing/selftests/rcutorture/bin/parse-build.sh @@ -28,7 +28,7 @@ F=$1 title=$2 -T=/tmp/parse-build.sh.$$ +T=${TMPDIR-/tmp}/parse-build.sh.$$ trap 'rm -rf $T' 0 mkdir $T diff --git a/tools/testing/selftests/rcutorture/bin/parse-torture.sh b/tools/testing/selftests/rcutorture/bin/parse-torture.sh index e3c5f0705696..f12c38909b00 100755 --- a/tools/testing/selftests/rcutorture/bin/parse-torture.sh +++ b/tools/testing/selftests/rcutorture/bin/parse-torture.sh @@ -27,7 +27,7 @@ # # Authors: Paul E. McKenney -T=/tmp/parse-torture.sh.$$ +T=${TMPDIR-/tmp}/parse-torture.sh.$$ file="$1" title="$2" -- cgit v1.2.1 From 564cbc87937d5de1b5b666b0ed68122d6c74fa07 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 23 Oct 2017 14:07:21 -0700 Subject: locking/atomics, selftests/powerpc: Convert ACCESS_ONCE() to READ_ONCE()/WRITE_ONCE() For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't currently harmful. However, for some features it is necessary to instrument reads and writes separately, which is not possible with ACCESS_ONCE(). This distinction is critical to correct operation. The bulk of the kernel code can be transformed via Coccinelle to use {READ,WRITE}_ONCE(), though this only modifies users of ACCESS_ONCE(), and not the implementation itself. As such, it has the potential to break homebrew ACCESS_ONCE() macros seen in some user code in the kernel tree (e.g. the virtio code, as fixed in commit ea9156fb3b71d9f7). To avoid fragility if/when that transformation occurs, and to align with the preferred usage of {READ,WRITE}_ONCE(), this patch updates the DSCR selftest code to use READ_ONCE() rather than ACCESS_ONCE(). There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Signed-off-by: Paul E. McKenney Acked-by: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Linus Torvalds Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Shuah Khan Cc: Thomas Gleixner Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-11-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- tools/testing/selftests/powerpc/dscr/dscr.h | 2 +- tools/testing/selftests/powerpc/dscr/dscr_default_test.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/powerpc/dscr/dscr.h b/tools/testing/selftests/powerpc/dscr/dscr.h index 18ea223bd398..cdb840bc54f2 100644 --- a/tools/testing/selftests/powerpc/dscr/dscr.h +++ b/tools/testing/selftests/powerpc/dscr/dscr.h @@ -39,7 +39,7 @@ #define rmb() asm volatile("lwsync":::"memory") #define wmb() asm volatile("lwsync":::"memory") -#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) +#define READ_ONCE(x) (*(volatile typeof(x) *)&(x)) /* Prilvilege state DSCR access */ inline unsigned long get_dscr(void) diff --git a/tools/testing/selftests/powerpc/dscr/dscr_default_test.c b/tools/testing/selftests/powerpc/dscr/dscr_default_test.c index df17c3bab0a7..9e1a37e93b63 100644 --- a/tools/testing/selftests/powerpc/dscr/dscr_default_test.c +++ b/tools/testing/selftests/powerpc/dscr/dscr_default_test.c @@ -27,7 +27,7 @@ static void *do_test(void *in) unsigned long d, cur_dscr, cur_dscr_usr; unsigned long s1, s2; - s1 = ACCESS_ONCE(sequence); + s1 = READ_ONCE(sequence); if (s1 & 1) continue; rmb(); -- cgit v1.2.1 From 5cd38016d0c88e3f67528c1a7380a6d5c90859e9 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 23 Oct 2017 14:07:23 -0700 Subject: locking/atomics, rcutorture/formal: Prepare for ACCESS_ONCE() removal For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't currently harmful. However, for some features it is necessary to instrument reads and writes separately, which is not possible with ACCESS_ONCE(). This distinction is critical to correct operation. The bulk of the kernel code can be transformed via Coccinelle to use {READ,WRITE}_ONCE(), though this only modifies users of ACCESS_ONCE(), and not the implementation itself. As such, it has the potential to break homebrew ACCESS_ONCE() macros seen in some user code in the kernel tree (e.g. the virtio code, as fixed in commit ea9156fb3b71d9f7). To avoid fragility if/when that transformation occurs, this patch reworks the definitions of {READ,WRITE}_ONCE() in the rcutorture formal tests, and removes the unused ACCESS_ONCE() helper. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Signed-off-by: Paul E. McKenney Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-13-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h index 6687acc08e6d..cc27b9ebcf20 100644 --- a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h +++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h @@ -34,8 +34,7 @@ #define rs_smp_mb() do {} while (0) #endif -#define ACCESS_ONCE(x) (*(volatile typeof(x) *) &(x)) -#define READ_ONCE(x) ACCESS_ONCE(x) -#define WRITE_ONCE(x, val) (ACCESS_ONCE(x) = (val)) +#define READ_ONCE(x) (*(volatile typeof(x) *) &(x)) +#define WRITE_ONCE(x) ((*(volatile typeof(x) *) &(x)) = (val)) #endif -- cgit v1.2.1 From 693cb5580fdb026922363aa103add64b3ecd572e Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 4 Nov 2017 04:19:48 -0700 Subject: selftests/x86/protection_keys: Fix syscall NR redefinition warnings On new enough glibc, the pkey syscalls numbers are available. Check first before defining them to avoid warnings like: protection_keys.c:198:0: warning: "SYS_pkey_alloc" redefined Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1fbef53a9e6befb7165ff855fc1a7d4788a191d6.1509794321.git.luto@kernel.org Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/protection_keys.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c index 555e43ca846b..7a1cc0e56d2d 100644 --- a/tools/testing/selftests/x86/protection_keys.c +++ b/tools/testing/selftests/x86/protection_keys.c @@ -189,17 +189,29 @@ void lots_o_noops_around_write(int *write_to_me) #define u64 uint64_t #ifdef __i386__ -#define SYS_mprotect_key 380 -#define SYS_pkey_alloc 381 -#define SYS_pkey_free 382 + +#ifndef SYS_mprotect_key +# define SYS_mprotect_key 380 +#endif +#ifndef SYS_pkey_alloc +# define SYS_pkey_alloc 381 +# define SYS_pkey_free 382 +#endif #define REG_IP_IDX REG_EIP #define si_pkey_offset 0x14 + #else -#define SYS_mprotect_key 329 -#define SYS_pkey_alloc 330 -#define SYS_pkey_free 331 + +#ifndef SYS_mprotect_key +# define SYS_mprotect_key 329 +#endif +#ifndef SYS_pkey_alloc +# define SYS_pkey_alloc 330 +# define SYS_pkey_free 331 +#endif #define REG_IP_IDX REG_RIP #define si_pkey_offset 0x20 + #endif void dump_mem(void *dumpme, int len_bytes) -- cgit v1.2.1 From d60ad744c9741586010d4bea286f09a063a90fbd Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 4 Nov 2017 04:19:49 -0700 Subject: selftests/x86/ldt_gdt: Robustify against set_thread_area() and LAR oddities Bits 19:16 of LAR's result are undefined, and some upcoming improvements to the test case seem to trigger this. Mask off those bits to avoid spurious failures. commit 5b781c7e317f ("x86/tls: Forcibly set the accessed bit in TLS segments") adds a valid case in which LAR's output doesn't quite agree with set_thread_area()'s input. This isn't triggered in the test as is, but it will be if we start calling set_thread_area() with the accessed bit clear. Work around this discrepency. I've added a Fixes tag so that -stable can pick this up if neccesary. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 5b781c7e317f ("x86/tls: Forcibly set the accessed bit in TLS segments") Link: http://lkml.kernel.org/r/b82f3f89c034b53580970ac865139fd8863f44e2.1509794321.git.luto@kernel.org Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/ldt_gdt.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/ldt_gdt.c b/tools/testing/selftests/x86/ldt_gdt.c index 961e3ee26c27..b0334338a4b0 100644 --- a/tools/testing/selftests/x86/ldt_gdt.c +++ b/tools/testing/selftests/x86/ldt_gdt.c @@ -115,7 +115,15 @@ static void check_valid_segment(uint16_t index, int ldt, return; } - if (ar != expected_ar) { + /* The SDM says "bits 19:16 are undefined". Thanks. */ + ar &= ~0xF0000; + + /* + * NB: Different Linux versions do different things with the + * accessed bit in set_thread_area(). + */ + if (ar != expected_ar && + (ldt || ar != (expected_ar | AR_ACCESSED))) { printf("[FAIL]\t%s entry %hu has AR 0x%08X but expected 0x%08X\n", (ldt ? "LDT" : "GDT"), index, ar, expected_ar); nerrs++; -- cgit v1.2.1 From d744dcad39094c9187075e274d1cdef79c57c8b5 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 4 Nov 2017 04:19:50 -0700 Subject: selftests/x86/ldt_gdt: Add infrastructure to test set_thread_area() Much of the test design could apply to set_thread_area() (i.e. GDT), not just modify_ldt(). Add set_thread_area() to the install_valid_mode() helper. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/02c23f8fba5547007f741dc24c3926e5284ede02.1509794321.git.luto@kernel.org Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/ldt_gdt.c | 53 ++++++++++++++++++++++++----------- 1 file changed, 37 insertions(+), 16 deletions(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/ldt_gdt.c b/tools/testing/selftests/x86/ldt_gdt.c index b0334338a4b0..45f30249133f 100644 --- a/tools/testing/selftests/x86/ldt_gdt.c +++ b/tools/testing/selftests/x86/ldt_gdt.c @@ -137,30 +137,51 @@ static void check_valid_segment(uint16_t index, int ldt, } } -static bool install_valid_mode(const struct user_desc *desc, uint32_t ar, - bool oldmode) +static bool install_valid_mode(const struct user_desc *d, uint32_t ar, + bool oldmode, bool ldt) { - int ret = syscall(SYS_modify_ldt, oldmode ? 1 : 0x11, - desc, sizeof(*desc)); - if (ret < -1) - errno = -ret; + struct user_desc desc = *d; + int ret; + + if (!ldt) { +#ifndef __i386__ + /* No point testing set_thread_area in a 64-bit build */ + return false; +#endif + if (!gdt_entry_num) + return false; + desc.entry_number = gdt_entry_num; + + ret = syscall(SYS_set_thread_area, &desc); + } else { + ret = syscall(SYS_modify_ldt, oldmode ? 1 : 0x11, + &desc, sizeof(desc)); + + if (ret < -1) + errno = -ret; + + if (ret != 0 && errno == ENOSYS) { + printf("[OK]\tmodify_ldt returned -ENOSYS\n"); + return false; + } + } + if (ret == 0) { - uint32_t limit = desc->limit; - if (desc->limit_in_pages) + uint32_t limit = desc.limit; + if (desc.limit_in_pages) limit = (limit << 12) + 4095; - check_valid_segment(desc->entry_number, 1, ar, limit, true); + check_valid_segment(desc.entry_number, ldt, ar, limit, true); return true; - } else if (errno == ENOSYS) { - printf("[OK]\tmodify_ldt returned -ENOSYS\n"); - return false; } else { - if (desc->seg_32bit) { - printf("[FAIL]\tUnexpected modify_ldt failure %d\n", + if (desc.seg_32bit) { + printf("[FAIL]\tUnexpected %s failure %d\n", + ldt ? "modify_ldt" : "set_thread_area", errno); nerrs++; return false; } else { - printf("[OK]\tmodify_ldt rejected 16 bit segment\n"); + printf("[OK]\t%s rejected 16 bit segment\n", + ldt ? "modify_ldt" : "set_thread_area"); return false; } } @@ -168,7 +189,7 @@ static bool install_valid_mode(const struct user_desc *desc, uint32_t ar, static bool install_valid(const struct user_desc *desc, uint32_t ar) { - return install_valid_mode(desc, ar, false); + return install_valid_mode(desc, ar, false, true); } static void install_invalid(const struct user_desc *desc, bool oldmode) -- cgit v1.2.1 From adedf2893c192dd09b1cc2f2dcfdd7cad99ec49d Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 4 Nov 2017 04:19:51 -0700 Subject: selftests/x86/ldt_gdt: Run most existing LDT test cases against the GDT as well Now that the main test infrastructure supports the GDT, run tests that will pass the kernel's GDT permission tests against the GDT. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/686a1eda63414da38fcecc2412db8dba1ae40581.1509794321.git.luto@kernel.org Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/ldt_gdt.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/ldt_gdt.c b/tools/testing/selftests/x86/ldt_gdt.c index 45f30249133f..3bb42fff5d66 100644 --- a/tools/testing/selftests/x86/ldt_gdt.c +++ b/tools/testing/selftests/x86/ldt_gdt.c @@ -189,7 +189,15 @@ static bool install_valid_mode(const struct user_desc *d, uint32_t ar, static bool install_valid(const struct user_desc *desc, uint32_t ar) { - return install_valid_mode(desc, ar, false, true); + bool ret = install_valid_mode(desc, ar, false, true); + + if (desc->contents <= 1 && desc->seg_32bit && + !desc->seg_not_present) { + /* Should work in the GDT, too. */ + install_valid_mode(desc, ar, false, false); + } + + return ret; } static void install_invalid(const struct user_desc *desc, bool oldmode) -- cgit v1.2.1 From fec8f5ae1715a01c72ad52cb2ecd8aacaf142302 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 4 Nov 2017 04:19:52 -0700 Subject: selftests/x86/ldt_get: Add a few additional tests for limits We weren't testing the .limit and .limit_in_pages fields very well. Add more tests. This addition seems to trigger the "bits 16:19 are undefined" issue that was fixed in an earlier patch. I think that, at least on my CPU, the high nibble of the limit ends in LAR bits 16:19. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/5601c15ea9b3113d288953fd2838b18bedf6bc67.1509794321.git.luto@kernel.org Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/ldt_gdt.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/ldt_gdt.c b/tools/testing/selftests/x86/ldt_gdt.c index 3bb42fff5d66..66e5ce5b91f0 100644 --- a/tools/testing/selftests/x86/ldt_gdt.c +++ b/tools/testing/selftests/x86/ldt_gdt.c @@ -404,9 +404,24 @@ static void do_simple_tests(void) install_invalid(&desc, false); desc.seg_not_present = 0; - desc.read_exec_only = 0; desc.seg_32bit = 1; + desc.read_exec_only = 0; + desc.limit = 0xfffff; + install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P | AR_DB); + + desc.limit_in_pages = 1; + + install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P | AR_DB | AR_G); + desc.read_exec_only = 1; + install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA | AR_S | AR_P | AR_DB | AR_G); + desc.contents = 1; + desc.read_exec_only = 0; + install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA_EXPDOWN | AR_S | AR_P | AR_DB | AR_G); + desc.read_exec_only = 1; + install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA_EXPDOWN | AR_S | AR_P | AR_DB | AR_G); + + desc.limit = 0; install_invalid(&desc, true); } -- cgit v1.2.1 From 9390afebe1d3f5a0be18b1afdd0ce09d67cebf9e Mon Sep 17 00:00:00 2001 From: Ricardo Neri Date: Sun, 5 Nov 2017 18:27:56 -0800 Subject: selftests/x86: Add tests for User-Mode Instruction Prevention Certain user space programs that run on virtual-8086 mode may utilize instructions protected by the User-Mode Instruction Prevention (UMIP) security feature present in new Intel processors: SGDT, SIDT and SMSW. In such a case, a general protection fault is issued if UMIP is enabled. When such a fault happens, the kernel traps it and emulates the results of these instructions with dummy values. The purpose of this new test is to verify whether the impacted instructions can be executed without causing such #GP. If no #GP exceptions occur, we expect to exit virtual-8086 mode from INT3. The instructions protected by UMIP are executed in representative use cases: a) displacement-only memory addressing b) register-indirect memory addressing c) results stored directly in operands Unfortunately, it is not possible to check the results against a set of expected values because no emulation will occur in systems that do not have the UMIP feature. Instead, results are printed for verification. A simple verification is done to ensure that results of all tests are identical. 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/1509935277-22138-12-git-send-email-ricardo.neri-calderon@linux.intel.com Signed-off-by: Ingo Molnar --- tools/testing/selftests/x86/entry_from_vm86.c | 73 ++++++++++++++++++++++++++- 1 file changed, 72 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c index d075ea0e5ca1..f7d9ceac7e06 100644 --- a/tools/testing/selftests/x86/entry_from_vm86.c +++ b/tools/testing/selftests/x86/entry_from_vm86.c @@ -95,6 +95,22 @@ asm ( "int3\n\t" "vmcode_int80:\n\t" "int $0x80\n\t" + "vmcode_umip:\n\t" + /* addressing via displacements */ + "smsw (2052)\n\t" + "sidt (2054)\n\t" + "sgdt (2060)\n\t" + /* addressing via registers */ + "mov $2066, %bx\n\t" + "smsw (%bx)\n\t" + "mov $2068, %bx\n\t" + "sidt (%bx)\n\t" + "mov $2074, %bx\n\t" + "sgdt (%bx)\n\t" + /* register operands, only for smsw */ + "smsw %ax\n\t" + "mov %ax, (2080)\n\t" + "int3\n\t" ".size vmcode, . - vmcode\n\t" "end_vmcode:\n\t" ".code32\n\t" @@ -103,7 +119,7 @@ asm ( extern unsigned char vmcode[], end_vmcode[]; extern unsigned char vmcode_bound[], vmcode_sysenter[], vmcode_syscall[], - vmcode_sti[], vmcode_int3[], vmcode_int80[]; + vmcode_sti[], vmcode_int3[], vmcode_int80[], vmcode_umip[]; /* Returns false if the test was skipped. */ static bool do_test(struct vm86plus_struct *v86, unsigned long eip, @@ -160,6 +176,58 @@ static bool do_test(struct vm86plus_struct *v86, unsigned long eip, return true; } +void do_umip_tests(struct vm86plus_struct *vm86, unsigned char *test_mem) +{ + struct table_desc { + unsigned short limit; + unsigned long base; + } __attribute__((packed)); + + /* Initialize variables with arbitrary values */ + struct table_desc gdt1 = { .base = 0x3c3c3c3c, .limit = 0x9999 }; + struct table_desc gdt2 = { .base = 0x1a1a1a1a, .limit = 0xaeae }; + struct table_desc idt1 = { .base = 0x7b7b7b7b, .limit = 0xf1f1 }; + struct table_desc idt2 = { .base = 0x89898989, .limit = 0x1313 }; + unsigned short msw1 = 0x1414, msw2 = 0x2525, msw3 = 3737; + + /* UMIP -- exit with INT3 unless kernel emulation did not trap #GP */ + do_test(vm86, vmcode_umip - vmcode, VM86_TRAP, 3, "UMIP tests"); + + /* Results from displacement-only addressing */ + msw1 = *(unsigned short *)(test_mem + 2052); + memcpy(&idt1, test_mem + 2054, sizeof(idt1)); + memcpy(&gdt1, test_mem + 2060, sizeof(gdt1)); + + /* Results from register-indirect addressing */ + msw2 = *(unsigned short *)(test_mem + 2066); + memcpy(&idt2, test_mem + 2068, sizeof(idt2)); + memcpy(&gdt2, test_mem + 2074, sizeof(gdt2)); + + /* Results when using register operands */ + msw3 = *(unsigned short *)(test_mem + 2080); + + printf("[INFO]\tResult from SMSW:[0x%04x]\n", msw1); + printf("[INFO]\tResult from SIDT: limit[0x%04x]base[0x%08lx]\n", + idt1.limit, idt1.base); + printf("[INFO]\tResult from SGDT: limit[0x%04x]base[0x%08lx]\n", + gdt1.limit, gdt1.base); + + if (msw1 != msw2 || msw1 != msw3) + printf("[FAIL]\tAll the results of SMSW should be the same.\n"); + else + printf("[PASS]\tAll the results from SMSW are identical.\n"); + + if (memcmp(&gdt1, &gdt2, sizeof(gdt1))) + printf("[FAIL]\tAll the results of SGDT should be the same.\n"); + else + printf("[PASS]\tAll the results from SGDT are identical.\n"); + + if (memcmp(&idt1, &idt2, sizeof(idt1))) + printf("[FAIL]\tAll the results of SIDT should be the same.\n"); + else + printf("[PASS]\tAll the results from SIDT are identical.\n"); +} + int main(void) { struct vm86plus_struct v86; @@ -218,6 +286,9 @@ int main(void) v86.regs.eax = (unsigned int)-1; do_test(&v86, vmcode_int80 - vmcode, VM86_INTx, 0x80, "int80"); + /* UMIP -- should exit with INTx 0x80 unless UMIP was not disabled */ + do_umip_tests(&v86, addr); + /* Execute a null pointer */ v86.regs.cs = 0; v86.regs.ss = 0; -- cgit v1.2.1 From a9e017d5619eb371460c8e516f4684def62bef3a Mon Sep 17 00:00:00 2001 From: Ricardo Neri Date: Sun, 5 Nov 2017 18:27:57 -0800 Subject: selftests/x86: Add tests for the STR and SLDT instructions 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 --- tools/testing/selftests/x86/entry_from_vm86.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests') diff --git a/tools/testing/selftests/x86/entry_from_vm86.c b/tools/testing/selftests/x86/entry_from_vm86.c index f7d9ceac7e06..361466a2eaef 100644 --- 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_struct *vm86, unsigned char *test_mem) 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) -- cgit v1.2.1