Buildroot 2019.02.8 (#533)

* Update Buildroot 2019.02.8

* Update patches

buildroot/package/libseccomp/0002-Circumvent-bug-in-uClibc-ng-syscall-on-x86_64-system.patch

@@ -0,0 +1,80 @@
+From 613e601bb4b50dc359b41f162a5b629449e4bbea Mon Sep 17 00:00:00 2001
+From: Carlos Santos <casantos@redhat.com>
+Date: Fri, 18 Oct 2019 22:02:49 -0300
+Subject: [PATCH] Circumvent bug in uClibc-ng syscall() on x86_64 systems
+
+On uClibc at least up to v1.0.32, syscall() for x86_64 is defined in
+libc/sysdeps/linux/x86_64/syscall.S as
+
+syscall:
+        movq %rdi, %rax         /* Syscall number -> rax.  */
+        movq %rsi, %rdi         /* shift arg1 - arg5.  */
+        movq %rdx, %rsi
+        movq %rcx, %rdx
+        movq %r8, %r10
+        movq %r9, %r8
+        movq 8(%rsp),%r9        /* arg6 is on the stack.  */
+        syscall                 /* Do the system call.  */
+        cmpq $-4095, %rax       /* Check %rax for error.  */
+        jae __syscall_error     /* Branch forward if it failed.  */
+        ret                     /* Return to caller.  */
+
+And __syscall_error is defined in
+libc/sysdeps/linux/x86_64/__syscall_error.c as
+
+int __syscall_error(void) attribute_hidden;
+int __syscall_error(void)
+{
+	register int err_no __asm__ ("%rcx");
+	__asm__ ("mov %rax, %rcx\n\t"
+	         "neg %rcx");
+	__set_errno(err_no);
+	return -1;
+}
+
+Notice that __syscall_error returns -1 as a 32-bit int in %rax, a 64-bit
+register i.e. 0x00000000ffffffff (decimal 4294967295). When this value
+is compared to -1 in _sys_chk_seccomp_flag_kernel() the result is false,
+leading the function to always return 0.
+
+Prevent the error by coercing the return value of syscall() to int in a
+temporary variable before comparing it to -1. We could use just an (int)
+cast but the variable makes the code more readable and the machine code
+generated by the compiler is the same in both cases.
+
+All other syscall() invocations were inspected and they either already
+coerce the result to int or do not compare it to -1.
+
+The same problem probably occurs on other 64-bit systems but so far only
+x86_64 was tested.
+
+A bug report is being submitted to uClibc.
+
+Signed-off-by: Carlos Santos <casantos@redhat.com>
+---
+ src/system.c | 8 +++++---
+ 1 file changed, 5 insertions(+), 3 deletions(-)
+
+diff --git a/src/system.c b/src/system.c
+index 8e5aafc..811b401 100644
+--- a/src/system.c
++++ b/src/system.c
+@@ -215,10 +215,12 @@ static int _sys_chk_seccomp_flag_kernel(int flag)
+ 	/* this is an invalid seccomp(2) call because the last argument
+ 	 * is NULL, but depending on the errno value of EFAULT we can
+ 	 * guess if the filter flag is supported or not */
+-	if (sys_chk_seccomp_syscall() == 1 &&
+-	    syscall(_nr_seccomp, SECCOMP_SET_MODE_FILTER, flag, NULL) == -1 &&
+-	    errno == EFAULT)
++	int rc;
++	if (sys_chk_seccomp_syscall() == 1) {
++	    rc = syscall(_nr_seccomp, SECCOMP_SET_MODE_FILTER, flag, NULL);
++	    if (rc == -1 && errno == EFAULT)
+ 		return 1;
++	}
+ 
+ 	return 0;
+ }
+-- 
+2.18.1
+

buildroot/package/libseccomp/libseccomp.hash

@@ -1,3 +1,3 @@
 # Locally calculated
-sha256 b7ee0299157fb7a6a81c99f2e0d7e64429b7d7c0eae43c3a6ef91e87eeed2868 libseccomp-v2.4.0.tar.gz
+sha256 36aa502c0461ae9efc6c93ec2430d6badd9bf91ecbe73806baf7b7c6f687ab4f libseccomp-2.4.1.tar.gz
 sha256 102900208eef27b766380135906d431dba87edaa7ec6aa72e6ebd3dd67f3a97b LICENSE

buildroot/package/libseccomp/libseccomp.mk

@@ -4,8 +4,8 @@
 #
 ################################################################################
 
-LIBSECCOMP_VERSION = v2.4.0
-LIBSECCOMP_SITE = $(call github,seccomp,libseccomp,$(LIBSECCOMP_VERSION))
+LIBSECCOMP_VERSION = 2.4.1
+LIBSECCOMP_SITE = $(call github,seccomp,libseccomp,v$(LIBSECCOMP_VERSION))
 LIBSECCOMP_LICENSE = LGPL-2.1
 LIBSECCOMP_LICENSE_FILES = LICENSE
 LIBSECCOMP_INSTALL_STAGING = YES