From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x224css6zTUGj4ezpsznthB0NJNNGTuC66WcUFF+IHGZEPPiY0CoHk0ivJOSzZPr8i4uYzVxq ARC-Seal: i=1; a=rsa-sha256; t=1519218069; cv=none; d=google.com; s=arc-20160816; b=UlIqQjB/JAxkYwvXbbhChUZJMmSe+VnafiuM9K55LL3akZVsy4VtM2dyXc4uhNzQbS BF5P6oHDMfFOvP8pecGyW9itghPmzcH2Vi52dp4fJlcXjjYwbPsj6AHpGoWt74uzgbkV p8aSFBGf987fwkfoQokREBxT4aF8U1w3NnknHoEtiCv44ib2dzc+0KLAREW/pqEj7ZDO YtfgLd8I5i3t9dW8GIRrVlLUICJtYBl4nboLi19rm129qNSIS1BXQC/e1sJYahPT0vpM lAoC46nynJRsKKgTRRgbC/j/OExbdp1ylJfBJb/GTqBB/BTlPvUy/6ZTDNc3E+no/nIV sTtw== 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=atGH7SW4QcLVkzjs89cyD/+v6RXhW+abaHXAkCi5ftM=; b=e5AyVTJlGUawV1ltSrPohmXzcTBe6JlPP/MuQPMX9eV1tja/9j83dnq/noNoI4QnKF W6Um6lNj0wJ5vUY7K9VhpO7f1PLfOxo9+vuoJpITlBplqjV5FB47WVGonAh9jUv+Tcgj xoi+u7FoTknzjCJ75eKJeBcHpVMBZ1Sq2d7VHIP3Is5qIjrIBLoVAT5XrssM4QASpsyf 1ni7V2V/c/M5a6lGPhwmAsqTVAZbuTG/QsWK9q+etUqKk8Gui2GrdZgHKymveqecOQWu N/nX0VycEoPQoAzi5m4KfEhQ/58iXR8i3OA579Z5Nj6kE/k2S0ptpzk3Tf+LVkWH7/PW jXKw== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 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 90.92.71.90 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, Dominik Brodowski , Andrew Lutomirski , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , linux-kselftest@vger.kernel.org, shuah@kernel.org, Ingo Molnar Subject: [PATCH 4.14 067/167] selftests/x86: Fix vDSO selftest segfault for vsyscall=none Date: Wed, 21 Feb 2018 13:47:58 +0100 Message-Id: <20180221124528.176139720@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180221124524.639039577@linuxfoundation.org> References: <20180221124524.639039577@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?1593015606048915198?= X-GMAIL-MSGID: =?utf-8?q?1593015606048915198?= 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: Dominik Brodowski 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 Cc: Andrew Lutomirski Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211111013.16888-3-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- 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,