diff --git a/getcanonname-use-after-free.patch b/getcanonname-use-after-free.patch new file mode 100644 index 0000000..94a0b37 --- /dev/null +++ b/getcanonname-use-after-free.patch @@ -0,0 +1,338 @@ +From 00ae4f10b504bc4564e9f22f00907093f1ab9338 Mon Sep 17 00:00:00 2001 +From: Siddhesh Poyarekar +Date: Fri, 15 Sep 2023 13:51:12 -0400 +Subject: [PATCH] getaddrinfo: Fix use after free in getcanonname + (CVE-2023-4806) + +When an NSS plugin only implements the _gethostbyname2_r and +_getcanonname_r callbacks, getaddrinfo could use memory that was freed +during tmpbuf resizing, through h_name in a previous query response. + +The backing store for res->at->name when doing a query with +gethostbyname3_r or gethostbyname2_r is tmpbuf, which is reallocated in +gethosts during the query. For AF_INET6 lookup with AI_ALL | +AI_V4MAPPED, gethosts gets called twice, once for a v6 lookup and second +for a v4 lookup. In this case, if the first call reallocates tmpbuf +enough number of times, resulting in a malloc, th->h_name (that +res->at->name refers to) ends up on a heap allocated storage in tmpbuf. +Now if the second call to gethosts also causes the plugin callback to +return NSS_STATUS_TRYAGAIN, tmpbuf will get freed, resulting in a UAF +reference in res->at->name. This then gets dereferenced in the +getcanonname_r plugin call, resulting in the use after free. + +Fix this by copying h_name over and freeing it at the end. This +resolves BZ #30843, which is assigned CVE-2023-4806. + +Signed-off-by: Siddhesh Poyarekar +(cherry picked from commit 973fe93a5675c42798b2161c6f29c01b0e243994) +--- + nss/Makefile | 15 ++++- + nss/nss_test_gai_hv2_canonname.c | 56 +++++++++++++++++ + nss/tst-nss-gai-hv2-canonname.c | 63 +++++++++++++++++++ + nss/tst-nss-gai-hv2-canonname.h | 1 + + .../postclean.req | 0 + .../tst-nss-gai-hv2-canonname.script | 2 + + sysdeps/posix/getaddrinfo.c | 25 +++++--- + 7 files changed, 152 insertions(+), 10 deletions(-) + create mode 100644 nss/nss_test_gai_hv2_canonname.c + create mode 100644 nss/tst-nss-gai-hv2-canonname.c + create mode 100644 nss/tst-nss-gai-hv2-canonname.h + create mode 100644 nss/tst-nss-gai-hv2-canonname.root/postclean.req + create mode 100644 nss/tst-nss-gai-hv2-canonname.root/tst-nss-gai-hv2-canonname.script + +diff --git a/nss/Makefile b/nss/Makefile +index 06fcdc450f..8a5126ecf3 100644 +--- a/nss/Makefile ++++ b/nss/Makefile +@@ -82,6 +82,7 @@ tests-container := \ + tst-nss-test3 \ + tst-reload1 \ + tst-reload2 \ ++ tst-nss-gai-hv2-canonname \ + # tests-container + + # Tests which need libdl +@@ -145,7 +146,8 @@ libnss_compat-inhibit-o = $(filter-out .os,$(object-suffixes)) + ifeq ($(build-static-nss),yes) + tests-static += tst-nss-static + endif +-extra-test-objs += nss_test1.os nss_test2.os nss_test_errno.os ++extra-test-objs += nss_test1.os nss_test2.os nss_test_errno.os \ ++ nss_test_gai_hv2_canonname.os + + include ../Rules + +@@ -180,12 +182,16 @@ rtld-tests-LDFLAGS += -Wl,--dynamic-list=nss_test.ver + libof-nss_test1 = extramodules + libof-nss_test2 = extramodules + libof-nss_test_errno = extramodules ++libof-nss_test_gai_hv2_canonname = extramodules + $(objpfx)/libnss_test1.so: $(objpfx)nss_test1.os $(link-libc-deps) + $(build-module) + $(objpfx)/libnss_test2.so: $(objpfx)nss_test2.os $(link-libc-deps) + $(build-module) + $(objpfx)/libnss_test_errno.so: $(objpfx)nss_test_errno.os $(link-libc-deps) + $(build-module) ++$(objpfx)/libnss_test_gai_hv2_canonname.so: \ ++ $(objpfx)nss_test_gai_hv2_canonname.os $(link-libc-deps) ++ $(build-module) + $(objpfx)nss_test2.os : nss_test1.c + # Use the nss_files suffix for these objects as well. + $(objpfx)/libnss_test1.so$(libnss_files.so-version): $(objpfx)/libnss_test1.so +@@ -195,10 +201,14 @@ $(objpfx)/libnss_test2.so$(libnss_files.so-version): $(objpfx)/libnss_test2.so + $(objpfx)/libnss_test_errno.so$(libnss_files.so-version): \ + $(objpfx)/libnss_test_errno.so + $(make-link) ++$(objpfx)/libnss_test_gai_hv2_canonname.so$(libnss_files.so-version): \ ++ $(objpfx)/libnss_test_gai_hv2_canonname.so ++ $(make-link) + $(patsubst %,$(objpfx)%.out,$(tests) $(tests-container)) : \ + $(objpfx)/libnss_test1.so$(libnss_files.so-version) \ + $(objpfx)/libnss_test2.so$(libnss_files.so-version) \ +- $(objpfx)/libnss_test_errno.so$(libnss_files.so-version) ++ $(objpfx)/libnss_test_errno.so$(libnss_files.so-version) \ ++ $(objpfx)/libnss_test_gai_hv2_canonname.so$(libnss_files.so-version) + + ifeq (yes,$(have-thread-library)) + $(objpfx)tst-cancel-getpwuid_r: $(shared-thread-library) +@@ -215,3 +225,4 @@ LDFLAGS-tst-nss-test3 = -Wl,--disable-new-dtags + LDFLAGS-tst-nss-test4 = -Wl,--disable-new-dtags + LDFLAGS-tst-nss-test5 = -Wl,--disable-new-dtags + LDFLAGS-tst-nss-test_errno = -Wl,--disable-new-dtags ++LDFLAGS-tst-nss-test_gai_hv2_canonname = -Wl,--disable-new-dtags +diff --git a/nss/nss_test_gai_hv2_canonname.c b/nss/nss_test_gai_hv2_canonname.c +new file mode 100644 +index 0000000000..4439c83c9f +--- /dev/null ++++ b/nss/nss_test_gai_hv2_canonname.c +@@ -0,0 +1,56 @@ ++/* NSS service provider that only provides gethostbyname2_r. ++ Copyright The GNU Toolchain Authors. ++ This file is part of the GNU C Library. ++ ++ The GNU C Library is free software; you can redistribute it and/or ++ modify it under the terms of the GNU Lesser General Public ++ License as published by the Free Software Foundation; either ++ version 2.1 of the License, or (at your option) any later version. ++ ++ The GNU C Library is distributed in the hope that it will be useful, ++ but WITHOUT ANY WARRANTY; without even the implied warranty of ++ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ++ Lesser General Public License for more details. ++ ++ You should have received a copy of the GNU Lesser General Public ++ License along with the GNU C Library; if not, see ++ . */ ++ ++#include ++#include ++#include ++#include "nss/tst-nss-gai-hv2-canonname.h" ++ ++/* Catch misnamed and functions. */ ++#pragma GCC diagnostic error "-Wmissing-prototypes" ++NSS_DECLARE_MODULE_FUNCTIONS (test_gai_hv2_canonname) ++ ++extern enum nss_status _nss_files_gethostbyname2_r (const char *, int, ++ struct hostent *, char *, ++ size_t, int *, int *); ++ ++enum nss_status ++_nss_test_gai_hv2_canonname_gethostbyname2_r (const char *name, int af, ++ struct hostent *result, ++ char *buffer, size_t buflen, ++ int *errnop, int *herrnop) ++{ ++ return _nss_files_gethostbyname2_r (name, af, result, buffer, buflen, errnop, ++ herrnop); ++} ++ ++enum nss_status ++_nss_test_gai_hv2_canonname_getcanonname_r (const char *name, char *buffer, ++ size_t buflen, char **result, ++ int *errnop, int *h_errnop) ++{ ++ /* We expect QUERYNAME, which is a small enough string that it shouldn't fail ++ the test. */ ++ if (memcmp (QUERYNAME, name, sizeof (QUERYNAME)) ++ || buflen < sizeof (QUERYNAME)) ++ abort (); ++ ++ strncpy (buffer, name, buflen); ++ *result = buffer; ++ return NSS_STATUS_SUCCESS; ++} +diff --git a/nss/tst-nss-gai-hv2-canonname.c b/nss/tst-nss-gai-hv2-canonname.c +new file mode 100644 +index 0000000000..d5f10c07d6 +--- /dev/null ++++ b/nss/tst-nss-gai-hv2-canonname.c +@@ -0,0 +1,63 @@ ++/* Test NSS query path for plugins that only implement gethostbyname2 ++ (#30843). ++ Copyright The GNU Toolchain Authors. ++ This file is part of the GNU C Library. ++ ++ The GNU C Library is free software; you can redistribute it and/or ++ modify it under the terms of the GNU Lesser General Public ++ License as published by the Free Software Foundation; either ++ version 2.1 of the License, or (at your option) any later version. ++ ++ The GNU C Library is distributed in the hope that it will be useful, ++ but WITHOUT ANY WARRANTY; without even the implied warranty of ++ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ++ Lesser General Public License for more details. ++ ++ You should have received a copy of the GNU Lesser General Public ++ License along with the GNU C Library; if not, see ++ . */ ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include "nss/tst-nss-gai-hv2-canonname.h" ++ ++#define PREPARE do_prepare ++ ++static void do_prepare (int a, char **av) ++{ ++ FILE *hosts = xfopen ("/etc/hosts", "w"); ++ for (unsigned i = 2; i < 255; i++) ++ { ++ fprintf (hosts, "ff01::ff02:ff03:%u:2\ttest.example.com\n", i); ++ fprintf (hosts, "192.168.0.%u\ttest.example.com\n", i); ++ } ++ xfclose (hosts); ++} ++ ++static int ++do_test (void) ++{ ++ __nss_configure_lookup ("hosts", "test_gai_hv2_canonname"); ++ ++ struct addrinfo hints = {}; ++ struct addrinfo *result = NULL; ++ ++ hints.ai_family = AF_INET6; ++ hints.ai_flags = AI_ALL | AI_V4MAPPED | AI_CANONNAME; ++ ++ int ret = getaddrinfo (QUERYNAME, NULL, &hints, &result); ++ ++ if (ret != 0) ++ FAIL_EXIT1 ("getaddrinfo failed: %s\n", gai_strerror (ret)); ++ ++ TEST_COMPARE_STRING (result->ai_canonname, QUERYNAME); ++ ++ freeaddrinfo(result); ++ return 0; ++} ++ ++#include +diff --git a/nss/tst-nss-gai-hv2-canonname.h b/nss/tst-nss-gai-hv2-canonname.h +new file mode 100644 +index 0000000000..14f2a9cb08 +--- /dev/null ++++ b/nss/tst-nss-gai-hv2-canonname.h +@@ -0,0 +1 @@ ++#define QUERYNAME "test.example.com" +diff --git a/nss/tst-nss-gai-hv2-canonname.root/postclean.req b/nss/tst-nss-gai-hv2-canonname.root/postclean.req +new file mode 100644 +index 0000000000..e69de29bb2 +diff --git a/nss/tst-nss-gai-hv2-canonname.root/tst-nss-gai-hv2-canonname.script b/nss/tst-nss-gai-hv2-canonname.root/tst-nss-gai-hv2-canonname.script +new file mode 100644 +index 0000000000..31848b4a28 +--- /dev/null ++++ b/nss/tst-nss-gai-hv2-canonname.root/tst-nss-gai-hv2-canonname.script +@@ -0,0 +1,2 @@ ++cp $B/nss/libnss_test_gai_hv2_canonname.so $L/libnss_test_gai_hv2_canonname.so.2 ++su +diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c +index 0356b622be..b2236b105c 100644 +--- a/sysdeps/posix/getaddrinfo.c ++++ b/sysdeps/posix/getaddrinfo.c +@@ -120,6 +120,7 @@ struct gaih_result + { + struct gaih_addrtuple *at; + char *canon; ++ char *h_name; + bool free_at; + bool got_ipv6; + }; +@@ -165,6 +166,7 @@ gaih_result_reset (struct gaih_result *res) + if (res->free_at) + free (res->at); + free (res->canon); ++ free (res->h_name); + memset (res, 0, sizeof (*res)); + } + +@@ -203,9 +205,8 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp, + return 0; + } + +-/* Convert struct hostent to a list of struct gaih_addrtuple objects. h_name +- is not copied, and the struct hostent object must not be deallocated +- prematurely. The new addresses are appended to the tuple array in RES. */ ++/* Convert struct hostent to a list of struct gaih_addrtuple objects. The new ++ addresses are appended to the tuple array in RES. */ + static bool + convert_hostent_to_gaih_addrtuple (const struct addrinfo *req, int family, + struct hostent *h, struct gaih_result *res) +@@ -238,6 +239,15 @@ convert_hostent_to_gaih_addrtuple (const struct addrinfo *req, int family, + res->at = array; + res->free_at = true; + ++ /* Duplicate h_name because it may get reclaimed when the underlying storage ++ is freed. */ ++ if (res->h_name == NULL) ++ { ++ res->h_name = __strdup (h->h_name); ++ if (res->h_name == NULL) ++ return false; ++ } ++ + /* Update the next pointers on reallocation. */ + for (size_t i = 0; i < old; i++) + array[i].next = array + i + 1; +@@ -262,7 +272,6 @@ convert_hostent_to_gaih_addrtuple (const struct addrinfo *req, int family, + } + array[i].next = array + i + 1; + } +- array[0].name = h->h_name; + array[count - 1].next = NULL; + + return true; +@@ -324,15 +333,15 @@ gethosts (nss_gethostbyname3_r fct, int family, const char *name, + memory allocation failure. The returned string is allocated on the + heap; the caller has to free it. */ + static char * +-getcanonname (nss_action_list nip, struct gaih_addrtuple *at, const char *name) ++getcanonname (nss_action_list nip, const char *hname, const char *name) + { + nss_getcanonname_r *cfct = __nss_lookup_function (nip, "getcanonname_r"); + char *s = (char *) name; + if (cfct != NULL) + { + char buf[256]; +- if (DL_CALL_FCT (cfct, (at->name ?: name, buf, sizeof (buf), +- &s, &errno, &h_errno)) != NSS_STATUS_SUCCESS) ++ if (DL_CALL_FCT (cfct, (hname ?: name, buf, sizeof (buf), &s, &errno, ++ &h_errno)) != NSS_STATUS_SUCCESS) + /* If the canonical name cannot be determined, use the passed + string. */ + s = (char *) name; +@@ -771,7 +780,7 @@ get_nss_addresses (const char *name, const struct addrinfo *req, + if ((req->ai_flags & AI_CANONNAME) != 0 + && res->canon == NULL) + { +- char *canonbuf = getcanonname (nip, res->at, name); ++ char *canonbuf = getcanonname (nip, res->h_name, name); + if (canonbuf == NULL) + { + __resolv_context_put (res_ctx); +-- +2.42.0 + diff --git a/glibc.changes b/glibc.changes index f78d8e6..667713e 100644 --- a/glibc.changes +++ b/glibc.changes @@ -1,3 +1,10 @@ +------------------------------------------------------------------- +Mon Sep 18 08:48:59 UTC 2023 - Andreas Schwab + +- getcanonname-use-after-free.patch: getaddrinfo: Fix use after free in + getcanonname (CVE-2023-4806, bsc#1215281, BZ #30843) +- Do not build any cross packages in SLES + ------------------------------------------------------------------- Wed Sep 13 12:25:56 UTC 2023 - Andreas Schwab diff --git a/glibc.spec b/glibc.spec index 1f623a6..8c021ad 100644 --- a/glibc.spec +++ b/glibc.spec @@ -96,6 +96,9 @@ ExclusiveArch: do_not_build %define build_cross 1 %undefine _build_create_debug ExcludeArch: %{cross_arch} +%if 0%{?suse_version} < 1600 +ExclusiveArch: do_not_build +%endif %endif %define host_arch %{?cross_cpu}%{!?cross_cpu:%{_target_cpu}} @@ -317,6 +320,8 @@ Patch1007: call-init-proxy-objects.patch Patch1008: dtors-reverse-ctor-order.patch # PATCH-FIX-UPSTREAM Stack read overflow with large TCP responses in no-aaaa mode (CVE-2023-4527, BZ #30842) Patch1009: no-aaaa-read-overflow.patch +# PATCH-FIX-UPSTREAM getaddrinfo: Fix use after free in getcanonname (CVE-2023-4806, BZ #30843) +Patch1010: getcanonname-use-after-free.patch ### # Patches awaiting upstream approval @@ -549,6 +554,7 @@ library in a cross compilation setting. %patch1007 -p1 %patch1008 -p1 %patch1009 -p1 +%patch1010 -p1 %endif %patch2000 -p1