diff --git a/glibc.changes b/glibc.changes index 6074a91..f4338b5 100644 --- a/glibc.changes +++ b/glibc.changes @@ -1,3 +1,11 @@ +------------------------------------------------------------------- +Wed Oct 4 09:31:09 UTC 2023 - Andreas Schwab + +- setxid-propagate-glibc-tunables.patch: Propagate GLIBC_TUNABLES in + setxid binaries +- tunables-string-parsing.patch: tunables: Terminate if end of input is + reached (CVE-2023-4911, bsc#1215501) + ------------------------------------------------------------------- Wed Sep 27 14:08:48 UTC 2023 - Andreas Schwab diff --git a/glibc.spec b/glibc.spec index 3d7993c..c2e7935 100644 --- a/glibc.spec +++ b/glibc.spec @@ -326,6 +326,10 @@ Patch1010: getcanonname-use-after-free.patch Patch1011: getaddrinfo-memory-leak.patch # PATCH-FIX-UPSTREAM io: Do not implement fstat with fstatat Patch1012: fstat-implementation.patch +# PATCH-FIX-UPSTREAM Propagate GLIBC_TUNABLES in setxid binaries +Patch1013: setxid-propagate-glibc-tunables.patch +# PATCH-FIX-UPSTREAM tunables: Terminate if end of input is reached (CVE-2023-4911) +Patch1014: tunables-string-parsing.patch ### # Patches awaiting upstream approval @@ -561,6 +565,8 @@ library in a cross compilation setting. %patch1010 -p1 %patch1011 -p1 %patch1012 -p1 +%patch1013 -p1 +%patch1014 -p1 %endif %patch2000 -p1 diff --git a/setxid-propagate-glibc-tunables.patch b/setxid-propagate-glibc-tunables.patch new file mode 100644 index 0000000..c94b734 --- /dev/null +++ b/setxid-propagate-glibc-tunables.patch @@ -0,0 +1,32 @@ +From 73e3fcd1a552783e66ff1f65c5f322e2f17a81d1 Mon Sep 17 00:00:00 2001 +From: Siddhesh Poyarekar +Date: Tue, 19 Sep 2023 13:25:40 -0400 +Subject: [PATCH] Propagate GLIBC_TUNABLES in setxid binaries + +GLIBC_TUNABLES scrubbing happens earlier than envvar scrubbing and some +tunables are required to propagate past setxid boundary, like their +env_alias. Rely on tunable scrubbing to clean out GLIBC_TUNABLES like +before, restoring behaviour in glibc 2.37 and earlier. + +Signed-off-by: Siddhesh Poyarekar +Reviewed-by: Carlos O'Donell +(cherry picked from commit 0d5f9ea97f1b39f2a855756078771673a68497e1) +--- + sysdeps/generic/unsecvars.h | 1 - + 1 file changed, 1 deletion(-) + +diff --git a/sysdeps/generic/unsecvars.h b/sysdeps/generic/unsecvars.h +index 81397fb90b..8278c50a84 100644 +--- a/sysdeps/generic/unsecvars.h ++++ b/sysdeps/generic/unsecvars.h +@@ -4,7 +4,6 @@ + #define UNSECURE_ENVVARS \ + "GCONV_PATH\0" \ + "GETCONF_DIR\0" \ +- "GLIBC_TUNABLES\0" \ + "HOSTALIASES\0" \ + "LD_AUDIT\0" \ + "LD_DEBUG\0" \ +-- +2.42.0 + diff --git a/tunables-string-parsing.patch b/tunables-string-parsing.patch new file mode 100644 index 0000000..b15b613 --- /dev/null +++ b/tunables-string-parsing.patch @@ -0,0 +1,157 @@ +From 750a45a783906a19591fb8ff6b7841470f1f5701 Mon Sep 17 00:00:00 2001 +From: Siddhesh Poyarekar +Date: Tue, 19 Sep 2023 18:39:32 -0400 +Subject: [PATCH] tunables: Terminate if end of input is reached + (CVE-2023-4911) + +The string parsing routine may end up writing beyond bounds of tunestr +if the input tunable string is malformed, of the form name=name=val. +This gets processed twice, first as name=name=val and next as name=val, +resulting in tunestr being name=name=val:name=val, thus overflowing +tunestr. + +Terminate the parsing loop at the first instance itself so that tunestr +does not overflow. + +This also fixes up tst-env-setuid-tunables to actually handle failures +correct and add new tests to validate the fix for this CVE. + +Signed-off-by: Siddhesh Poyarekar +Reviewed-by: Carlos O'Donell +(cherry picked from commit 1056e5b4c3f2d90ed2b4a55f96add28da2f4c8fa) +--- + NEWS | 5 +++++ + elf/dl-tunables.c | 17 +++++++++------- + elf/tst-env-setuid-tunables.c | 37 +++++++++++++++++++++++++++-------- + 3 files changed, 44 insertions(+), 15 deletions(-) + +diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c +index 62b7332d95..cae67efa0a 100644 +--- a/elf/dl-tunables.c ++++ b/elf/dl-tunables.c +@@ -180,11 +180,7 @@ parse_tunables (char *tunestr, char *valstring) + /* If we reach the end of the string before getting a valid name-value + pair, bail out. */ + if (p[len] == '\0') +- { +- if (__libc_enable_secure) +- tunestr[off] = '\0'; +- return; +- } ++ break; + + /* We did not find a valid name-value pair before encountering the + colon. */ +@@ -244,9 +240,16 @@ parse_tunables (char *tunestr, char *valstring) + } + } + +- if (p[len] != '\0') +- p += len + 1; ++ /* We reached the end while processing the tunable string. */ ++ if (p[len] == '\0') ++ break; ++ ++ p += len + 1; + } ++ ++ /* Terminate tunestr before we leave. */ ++ if (__libc_enable_secure) ++ tunestr[off] = '\0'; + } + + /* Enable the glibc.malloc.check tunable in SETUID/SETGID programs only when +diff --git a/elf/tst-env-setuid-tunables.c b/elf/tst-env-setuid-tunables.c +index 7dfb0e073a..f0b92c97e7 100644 +--- a/elf/tst-env-setuid-tunables.c ++++ b/elf/tst-env-setuid-tunables.c +@@ -50,6 +50,8 @@ const char *teststrings[] = + "glibc.malloc.perturb=0x800:not_valid.malloc.check=2:glibc.malloc.mmap_threshold=4096", + "glibc.not_valid.check=2:glibc.malloc.mmap_threshold=4096", + "not_valid.malloc.check=2:glibc.malloc.mmap_threshold=4096", ++ "glibc.malloc.mmap_threshold=glibc.malloc.mmap_threshold=4096", ++ "glibc.malloc.check=2", + "glibc.malloc.garbage=2:glibc.maoc.mmap_threshold=4096:glibc.malloc.check=2", + "glibc.malloc.check=4:glibc.malloc.garbage=2:glibc.maoc.mmap_threshold=4096", + ":glibc.malloc.garbage=2:glibc.malloc.check=1", +@@ -68,6 +70,8 @@ const char *resultstrings[] = + "glibc.malloc.perturb=0x800:glibc.malloc.mmap_threshold=4096", + "glibc.malloc.mmap_threshold=4096", + "glibc.malloc.mmap_threshold=4096", ++ "glibc.malloc.mmap_threshold=glibc.malloc.mmap_threshold=4096", ++ "", + "", + "", + "", +@@ -81,11 +85,18 @@ test_child (int off) + { + const char *val = getenv ("GLIBC_TUNABLES"); + ++ printf (" [%d] GLIBC_TUNABLES is %s\n", off, val); ++ fflush (stdout); + if (val != NULL && strcmp (val, resultstrings[off]) == 0) + return 0; + + if (val != NULL) +- printf ("[%d] Unexpected GLIBC_TUNABLES VALUE %s\n", off, val); ++ printf (" [%d] Unexpected GLIBC_TUNABLES VALUE %s, expected %s\n", ++ off, val, resultstrings[off]); ++ else ++ printf (" [%d] GLIBC_TUNABLES environment variable absent\n", off); ++ ++ fflush (stdout); + + return 1; + } +@@ -106,21 +117,26 @@ do_test (int argc, char **argv) + if (ret != 0) + exit (1); + +- exit (EXIT_SUCCESS); ++ /* Special return code to make sure that the child executed all the way ++ through. */ ++ exit (42); + } + else + { +- int ret = 0; +- + /* Spawn tests. */ + for (int i = 0; i < array_length (teststrings); i++) + { + char buf[INT_BUFSIZE_BOUND (int)]; + +- printf ("Spawned test for %s (%d)\n", teststrings[i], i); ++ printf ("[%d] Spawned test for %s\n", i, teststrings[i]); + snprintf (buf, sizeof (buf), "%d\n", i); ++ fflush (stdout); + if (setenv ("GLIBC_TUNABLES", teststrings[i], 1) != 0) +- exit (1); ++ { ++ printf (" [%d] Failed to set GLIBC_TUNABLES: %m", i); ++ support_record_failure (); ++ continue; ++ } + + int status = support_capture_subprogram_self_sgid (buf); + +@@ -128,9 +144,14 @@ do_test (int argc, char **argv) + if (WEXITSTATUS (status) == EXIT_UNSUPPORTED) + return EXIT_UNSUPPORTED; + +- ret |= status; ++ if (WEXITSTATUS (status) != 42) ++ { ++ printf (" [%d] child failed with status %d\n", i, ++ WEXITSTATUS (status)); ++ support_record_failure (); ++ } + } +- return ret; ++ return 0; + } + } + +-- +2.42.0 +