diff --git a/U_Use-getentropy-if-arc4random_buf-is-not-available.patch b/U_Use-getentropy-if-arc4random_buf-is-not-available.patch new file mode 100644 index 0000000..99eeb1f --- /dev/null +++ b/U_Use-getentropy-if-arc4random_buf-is-not-available.patch @@ -0,0 +1,142 @@ +From ff5e59f32255913bb1cdf51441b98c9107ae165b Mon Sep 17 00:00:00 2001 +From: Benjamin Tissoires +Date: Tue, 4 Apr 2017 19:12:53 +0200 +Subject: [PATCH] Use getentropy() if arc4random_buf() is not available + +This allows to fix CVE-2017-2626 on Linux platforms without pulling in +libbsd. +The libc getentropy() is available since glibc 2.25 but also on OpenBSD. +For Linux, we need at least a v3.17 kernel. If the recommended +arc4random_buf() function is not available, emulate it by first trying +to use getentropy() on a supported glibc and kernel. If the call fails, +fall back to the current (partly vulnerable) code. + +Signed-off-by: Benjamin Tissoires +Reviewed-by: Mark Kettenis +Reviewed-by: Alan Coopersmith +Signed-off-by: Peter Hutterer +--- + configure.ac | 2 +- + src/iceauth.c | 65 ++++++++++++++++++++++++++++++++++++++++++----------------- + 2 files changed, 47 insertions(+), 20 deletions(-) + +diff --git a/configure.ac b/configure.ac +index 458882a..c971ab6 100644 +--- a/configure.ac ++++ b/configure.ac +@@ -38,7 +38,7 @@ AC_DEFINE(ICE_t, 1, [Xtrans transport type]) + + # Checks for library functions. + AC_CHECK_LIB([bsd], [arc4random_buf]) +-AC_CHECK_FUNCS([asprintf arc4random_buf]) ++AC_CHECK_FUNCS([asprintf arc4random_buf getentropy]) + + # Allow checking code with lint, sparse, etc. + XORG_WITH_LINT +diff --git a/src/iceauth.c b/src/iceauth.c +index ed31683..de4785b 100644 +--- a/src/iceauth.c ++++ b/src/iceauth.c +@@ -44,31 +44,19 @@ Author: Ralph Mor, X Consortium + + static int was_called_state; + +-/* +- * MIT-MAGIC-COOKIE-1 is a sample authentication method implemented by +- * the SI. It is not part of standard ICElib. +- */ ++#ifndef HAVE_ARC4RANDOM_BUF + +- +-char * +-IceGenerateMagicCookie ( ++static void ++emulate_getrandom_buf ( ++ char *auth, + int len + ) + { +- char *auth; +-#ifndef HAVE_ARC4RANDOM_BUF + long ldata[2]; + int seed; + int value; + int i; +-#endif + +- if ((auth = malloc (len + 1)) == NULL) +- return (NULL); +- +-#ifdef HAVE_ARC4RANDOM_BUF +- arc4random_buf(auth, len); +-#else + #ifdef ITIMER_REAL + { + struct timeval now; +@@ -76,13 +64,13 @@ IceGenerateMagicCookie ( + ldata[0] = now.tv_sec; + ldata[1] = now.tv_usec; + } +-#else ++#else /* ITIMER_REAL */ + { + long time (); + ldata[0] = time ((long *) 0); + ldata[1] = getpid (); + } +-#endif ++#endif /* ITIMER_REAL */ + seed = (ldata[0]) + (ldata[1] << 16); + srand (seed); + for (i = 0; i < len; i++) +@@ -90,7 +78,46 @@ IceGenerateMagicCookie ( + value = rand (); + auth[i] = value & 0xff; + } +-#endif ++} ++ ++static void ++arc4random_buf ( ++ char *auth, ++ int len ++) ++{ ++ int ret; ++ ++#if HAVE_GETENTROPY ++ /* weak emulation of arc4random through the entropy libc */ ++ ret = getentropy (auth, len); ++ if (ret == 0) ++ return; ++#endif /* HAVE_GETENTROPY */ ++ ++ emulate_getrandom_buf (auth, len); ++} ++ ++#endif /* !defined(HAVE_ARC4RANDOM_BUF) */ ++ ++/* ++ * MIT-MAGIC-COOKIE-1 is a sample authentication method implemented by ++ * the SI. It is not part of standard ICElib. ++ */ ++ ++ ++char * ++IceGenerateMagicCookie ( ++ int len ++) ++{ ++ char *auth; ++ ++ if ((auth = malloc (len + 1)) == NULL) ++ return (NULL); ++ ++ arc4random_buf (auth, len); ++ + auth[len] = '\0'; + return (auth); + } +-- +2.12.3 + diff --git a/libICE.changes b/libICE.changes index 75ff2a2..9b83511 100644 --- a/libICE.changes +++ b/libICE.changes @@ -1,3 +1,10 @@ +------------------------------------------------------------------- +Sun Jun 11 18:00:24 UTC 2017 - sndirsch@suse.com + +- U_Use-getentropy-if-arc4random_buf-is-not-available.patch + * Use getentropy() if arc4random_buf() is not available + (bnc#1025068, CVE-2017-2626) + ------------------------------------------------------------------- Tue Jun 10 15:32:39 UTC 2014 - sndirsch@suse.com diff --git a/libICE.spec b/libICE.spec index efbd29e..c36127f 100644 --- a/libICE.spec +++ b/libICE.spec @@ -1,7 +1,7 @@ # # spec file for package libICE # -# Copyright (c) 2014 SUSE LINUX Products GmbH, Nuernberg, Germany. +# Copyright (c) 2017 SUSE LINUX GmbH, Nuernberg, Germany. # # All modifications and additions to the file contributed by third parties # remain the property of their copyright owners, unless otherwise agreed @@ -28,6 +28,7 @@ Url: http://xorg.freedesktop.org/ #Git-Clone: git://anongit.freedesktop.org/xorg/lib/libICE #Git-Web: http://cgit.freedesktop.org/xorg/lib/libICE/ Source: http://xorg.freedesktop.org/releases/individual/lib/%{name}-%{version}.tar.bz2 +Patch0: U_Use-getentropy-if-arc4random_buf-is-not-available.patch BuildRoot: %{_tmppath}/%{name}-%{version}-build #git#BuildRequires: autoconf >= 2.60, automake, libtool BuildRequires: pkgconfig @@ -46,8 +47,8 @@ transport connection. %package -n %lname Summary: X11 Inter-Client Exchange Library -Group: System/Libraries # O/P added for 12.2 +Group: System/Libraries Provides: xorg-x11-libICE = 7.6_%version-%release Obsoletes: xorg-x11-libICE < 7.6_%version-%release