This is a note to let you know that I've just added the patch titled
selftests/x86: Fix vDSO selftest segfault for vsyscall=none
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-x86-fix-vdso-selftest-segfault-for-vsyscall-none.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 198ee8e17502da2634f7366395db1d77630e0219 Mon Sep 17 00:00:00 2001
From: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Date: Sun, 11 Feb 2018 12:10:10 +0100
Subject: selftests/x86: Fix vDSO selftest segfault for vsyscall=none
From: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
commit 198ee8e17502da2634f7366395db1d77630e0219 upstream.
The vDSO selftest tries to execute a vsyscall unconditionally, even if it
is not present on the test system (e.g. if booted with vsyscall=none or
with CONFIG_LEGACY_VSYSCALL_NONE=y set. Fix this by copying (and tweaking)
the vsyscall check from test_vsyscall.c
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Cc: Andrew Lutomirski <luto@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Cc: shuah@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20180211111013.16888-3-linux@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/x86/test_vdso.c | 50 +++++++++++++++++++++++++++-----
1 file changed, 43 insertions(+), 7 deletions(-)
--- a/tools/testing/selftests/x86/test_vdso.c
+++ b/tools/testing/selftests/x86/test_vdso.c
@@ -28,18 +28,52 @@
int nerrs = 0;
+typedef long (*getcpu_t)(unsigned *, unsigned *, void *);
+
+getcpu_t vgetcpu;
+getcpu_t vdso_getcpu;
+
+static void *vsyscall_getcpu(void)
+{
#ifdef __x86_64__
-# define VSYS(x) (x)
+ FILE *maps;
+ char line[128];
+ bool found = false;
+
+ maps = fopen("/proc/self/maps", "r");
+ if (!maps) /* might still be present, but ignore it here, as we test vDSO not vsyscall */
+ return NULL;
+
+ while (fgets(line, sizeof(line), maps)) {
+ char r, x;
+ void *start, *end;
+ char name[128];
+ if (sscanf(line, "%p-%p %c-%cp %*x %*x:%*x %*u %s",
+ &start, &end, &r, &x, name) != 5)
+ continue;
+
+ if (strcmp(name, "[vsyscall]"))
+ continue;
+
+ /* assume entries are OK, as we test vDSO here not vsyscall */
+ found = true;
+ break;
+ }
+
+ fclose(maps);
+
+ if (!found) {
+ printf("Warning: failed to find vsyscall getcpu\n");
+ return NULL;
+ }
+ return (void *) (0xffffffffff600800);
#else
-# define VSYS(x) 0
+ return NULL;
#endif
+}
-typedef long (*getcpu_t)(unsigned *, unsigned *, void *);
-
-const getcpu_t vgetcpu = (getcpu_t)VSYS(0xffffffffff600800);
-getcpu_t vdso_getcpu;
-void fill_function_pointers()
+static void fill_function_pointers()
{
void *vdso = dlopen("linux-vdso.so.1",
RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
@@ -54,6 +88,8 @@ void fill_function_pointers()
vdso_getcpu = (getcpu_t)dlsym(vdso, "__vdso_getcpu");
if (!vdso_getcpu)
printf("Warning: failed to find getcpu in vDSO\n");
+
+ vgetcpu = (getcpu_t) vsyscall_getcpu();
}
static long sys_getcpu(unsigned * cpu, unsigned * node,
Patches currently in stable-queue which might be from linux@xxxxxxxxxxxxxxxxxxxx are
queue-4.14/x86-entry-64-interleave-xor-register-clearing-with-push-instructions.patch
queue-4.14/x86-entry-64-merge-the-pop_c_regs-and-pop_extra_regs-macros-into-a-single-pop_regs-macro.patch
queue-4.14/x86-entry-64-remove-the-unused-icebp-macro.patch
queue-4.14/x86-entry-64-use-push_and_clean_regs-in-more-cases.patch
queue-4.14/selftests-x86-disable-tests-requiring-32-bit-support-on-pure-64-bit-systems.patch
queue-4.14/x86-entry-64-fix-paranoid_entry-frame-pointer-warning.patch
queue-4.14/x86-entry-64-merge-save_c_regs-and-save_extra_regs-remove-unused-extensions.patch
queue-4.14/selftests-x86-do-not-rely-on-int-0x80-in-single_step_syscall.c.patch
queue-4.14/selftests-x86-fix-vdso-selftest-segfault-for-vsyscall-none.patch
queue-4.14/x86-entry-64-indent-push_and_clear_regs-and-pop_regs-properly.patch
queue-4.14/selftests-x86-clean-up-and-document-sscanf-usage.patch
queue-4.14/selftests-x86-do-not-rely-on-int-0x80-in-test_mremap_vdso.c.patch
queue-4.14/x86-entry-64-get-rid-of-the-alloc_pt_gpregs_on_stack-and-save_and_clear_regs-macros.patch
queue-4.14/x86-entry-64-introduce-the-push_and_clean_regs-macro.patch