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-rw-r--r--source/l/glibc/patches/glibc.CVE-2021-3999.patch356
1 files changed, 0 insertions, 356 deletions
diff --git a/source/l/glibc/patches/glibc.CVE-2021-3999.patch b/source/l/glibc/patches/glibc.CVE-2021-3999.patch
deleted file mode 100644
index 0644f798a..000000000
--- a/source/l/glibc/patches/glibc.CVE-2021-3999.patch
+++ /dev/null
@@ -1,356 +0,0 @@
-From 472e799a5f2102bc0c3206dbd5a801765fceb39c Mon Sep 17 00:00:00 2001
-From: Siddhesh Poyarekar <siddhesh@sourceware.org>
-Date: Fri, 21 Jan 2022 23:32:56 +0530
-Subject: [PATCH] getcwd: Set errno to ERANGE for size == 1 (CVE-2021-3999)
-
-No valid path returned by getcwd would fit into 1 byte, so reject the
-size early and return NULL with errno set to ERANGE. This change is
-prompted by CVE-2021-3999, which describes a single byte buffer
-underflow and overflow when all of the following conditions are met:
-
-- The buffer size (i.e. the second argument of getcwd) is 1 byte
-- The current working directory is too long
-- '/' is also mounted on the current working directory
-
-Sequence of events:
-
-- In sysdeps/unix/sysv/linux/getcwd.c, the syscall returns ENAMETOOLONG
- because the linux kernel checks for name length before it checks
- buffer size
-
-- The code falls back to the generic getcwd in sysdeps/posix
-
-- In the generic func, the buf[0] is set to '\0' on line 250
-
-- this while loop on line 262 is bypassed:
-
- while (!(thisdev == rootdev && thisino == rootino))
-
- since the rootfs (/) is bind mounted onto the directory and the flow
- goes on to line 449, where it puts a '/' in the byte before the
- buffer.
-
-- Finally on line 458, it moves 2 bytes (the underflowed byte and the
- '\0') to the buf[0] and buf[1], resulting in a 1 byte buffer overflow.
-
-- buf is returned on line 469 and errno is not set.
-
-This resolves BZ #28769.
-
-Reviewed-by: Andreas Schwab <schwab@linux-m68k.org>
-Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
-Signed-off-by: Qualys Security Advisory <qsa@qualys.com>
-Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
-(cherry picked from commit 23e0e8f5f1fb5ed150253d986ecccdc90c2dcd5e)
----
- NEWS | 6 +
- sysdeps/posix/getcwd.c | 7 +
- sysdeps/unix/sysv/linux/Makefile | 7 +-
- .../unix/sysv/linux/tst-getcwd-smallbuff.c | 241 ++++++++++++++++++
- 4 files changed, 260 insertions(+), 1 deletion(-)
- create mode 100644 sysdeps/unix/sysv/linux/tst-getcwd-smallbuff.c
-
-diff --git a/NEWS b/NEWS
-index b4f81c2668..8d7467d2c1 100644
---- a/NEWS
-+++ b/NEWS
-@@ -20,6 +20,12 @@ Security related changes:
- function could result in a memory leak and potential access of
- uninitialized memory. Reported by Qualys.
-
-+ CVE-2021-3999: Passing a buffer of size exactly 1 byte to the getcwd
-+ function may result in an off-by-one buffer underflow and overflow
-+ when the current working directory is longer than PATH_MAX and also
-+ corresponds to the / directory through an unprivileged mount
-+ namespace. Reported by Qualys.
-+
- The following bugs are resolved with this release:
-
- [12889] nptl: Fix race between pthread_kill and thread exit
-diff --git a/sysdeps/posix/getcwd.c b/sysdeps/posix/getcwd.c
-index 13680026ff..b6984a382c 100644
---- a/sysdeps/posix/getcwd.c
-+++ b/sysdeps/posix/getcwd.c
-@@ -187,6 +187,13 @@ __getcwd_generic (char *buf, size_t size)
- size_t allocated = size;
- size_t used;
-
-+ /* A size of 1 byte is never useful. */
-+ if (allocated == 1)
-+ {
-+ __set_errno (ERANGE);
-+ return NULL;
-+ }
-+
- #if HAVE_MINIMALLY_WORKING_GETCWD
- /* If AT_FDCWD is not defined, the algorithm below is O(N**2) and
- this is much slower than the system getcwd (at least on
-diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
-index 76ad06361c..9380d3848d 100644
---- a/sysdeps/unix/sysv/linux/Makefile
-+++ b/sysdeps/unix/sysv/linux/Makefile
-@@ -331,7 +331,12 @@ sysdep_routines += xstatconv internal_statvfs \
-
- sysdep_headers += bits/fcntl-linux.h
-
--tests += tst-fallocate tst-fallocate64 tst-o_path-locks
-+tests += \
-+ tst-fallocate \
-+ tst-fallocate64 \
-+ tst-getcwd-smallbuff \
-+ tst-o_path-locks \
-+# tests
- endif
-
- ifeq ($(subdir),elf)
-diff --git a/sysdeps/unix/sysv/linux/tst-getcwd-smallbuff.c b/sysdeps/unix/sysv/linux/tst-getcwd-smallbuff.c
-new file mode 100644
-index 0000000000..d460d6e766
---- /dev/null
-+++ b/sysdeps/unix/sysv/linux/tst-getcwd-smallbuff.c
-@@ -0,0 +1,241 @@
-+/* Verify that getcwd returns ERANGE for size 1 byte and does not underflow
-+ buffer when the CWD is too long and is also a mount target of /. See bug
-+ #28769 or CVE-2021-3999 for more context.
-+ 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
-+ <https://www.gnu.org/licenses/>. */
-+
-+#include <errno.h>
-+#include <fcntl.h>
-+#include <intprops.h>
-+#include <limits.h>
-+#include <stdio.h>
-+#include <stdlib.h>
-+#include <string.h>
-+#include <sys/mount.h>
-+#include <sys/stat.h>
-+#include <sys/types.h>
-+#include <sys/wait.h>
-+
-+#include <sys/socket.h>
-+#include <sys/un.h>
-+#include <support/check.h>
-+#include <support/temp_file.h>
-+#include <support/xsched.h>
-+#include <support/xunistd.h>
-+
-+static char *base;
-+#define BASENAME "tst-getcwd-smallbuff"
-+#define MOUNT_NAME "mpoint"
-+static int sockfd[2];
-+
-+static void
-+do_cleanup (void)
-+{
-+ support_chdir_toolong_temp_directory (base);
-+ TEST_VERIFY_EXIT (rmdir (MOUNT_NAME) == 0);
-+ free (base);
-+}
-+
-+static void
-+send_fd (const int sock, const int fd)
-+{
-+ struct msghdr msg = {0};
-+ union
-+ {
-+ struct cmsghdr hdr;
-+ char buf[CMSG_SPACE (sizeof (int))];
-+ } cmsgbuf = {0};
-+ struct cmsghdr *cmsg;
-+ struct iovec vec;
-+ char ch = 'A';
-+ ssize_t n;
-+
-+ msg.msg_control = &cmsgbuf.buf;
-+ msg.msg_controllen = sizeof (cmsgbuf.buf);
-+
-+ cmsg = CMSG_FIRSTHDR (&msg);
-+ cmsg->cmsg_len = CMSG_LEN (sizeof (int));
-+ cmsg->cmsg_level = SOL_SOCKET;
-+ cmsg->cmsg_type = SCM_RIGHTS;
-+ memcpy (CMSG_DATA (cmsg), &fd, sizeof (fd));
-+
-+ vec.iov_base = &ch;
-+ vec.iov_len = 1;
-+ msg.msg_iov = &vec;
-+ msg.msg_iovlen = 1;
-+
-+ while ((n = sendmsg (sock, &msg, 0)) == -1 && errno == EINTR);
-+
-+ TEST_VERIFY_EXIT (n == 1);
-+}
-+
-+static int
-+recv_fd (const int sock)
-+{
-+ struct msghdr msg = {0};
-+ union
-+ {
-+ struct cmsghdr hdr;
-+ char buf[CMSG_SPACE(sizeof(int))];
-+ } cmsgbuf = {0};
-+ struct cmsghdr *cmsg;
-+ struct iovec vec;
-+ ssize_t n;
-+ char ch = '\0';
-+ int fd = -1;
-+
-+ vec.iov_base = &ch;
-+ vec.iov_len = 1;
-+ msg.msg_iov = &vec;
-+ msg.msg_iovlen = 1;
-+
-+ msg.msg_control = &cmsgbuf.buf;
-+ msg.msg_controllen = sizeof (cmsgbuf.buf);
-+
-+ while ((n = recvmsg (sock, &msg, 0)) == -1 && errno == EINTR);
-+ if (n != 1 || ch != 'A')
-+ return -1;
-+
-+ cmsg = CMSG_FIRSTHDR (&msg);
-+ if (cmsg == NULL)
-+ return -1;
-+ if (cmsg->cmsg_type != SCM_RIGHTS)
-+ return -1;
-+ memcpy (&fd, CMSG_DATA (cmsg), sizeof (fd));
-+ if (fd < 0)
-+ return -1;
-+ return fd;
-+}
-+
-+static int
-+child_func (void * const arg)
-+{
-+ xclose (sockfd[0]);
-+ const int sock = sockfd[1];
-+ char ch;
-+
-+ TEST_VERIFY_EXIT (read (sock, &ch, 1) == 1);
-+ TEST_VERIFY_EXIT (ch == '1');
-+
-+ if (mount ("/", MOUNT_NAME, NULL, MS_BIND | MS_REC, NULL))
-+ FAIL_EXIT1 ("mount failed: %m\n");
-+ const int fd = xopen ("mpoint",
-+ O_RDONLY | O_PATH | O_DIRECTORY | O_NOFOLLOW, 0);
-+
-+ send_fd (sock, fd);
-+ xclose (fd);
-+
-+ TEST_VERIFY_EXIT (read (sock, &ch, 1) == 1);
-+ TEST_VERIFY_EXIT (ch == 'a');
-+
-+ xclose (sock);
-+ return 0;
-+}
-+
-+static void
-+update_map (char * const mapping, const char * const map_file)
-+{
-+ const size_t map_len = strlen (mapping);
-+
-+ const int fd = xopen (map_file, O_WRONLY, 0);
-+ xwrite (fd, mapping, map_len);
-+ xclose (fd);
-+}
-+
-+static void
-+proc_setgroups_write (const long child_pid, const char * const str)
-+{
-+ const size_t str_len = strlen(str);
-+
-+ char setgroups_path[sizeof ("/proc//setgroups") + INT_STRLEN_BOUND (long)];
-+
-+ snprintf (setgroups_path, sizeof (setgroups_path),
-+ "/proc/%ld/setgroups", child_pid);
-+
-+ const int fd = open (setgroups_path, O_WRONLY);
-+
-+ if (fd < 0)
-+ {
-+ TEST_VERIFY_EXIT (errno == ENOENT);
-+ FAIL_UNSUPPORTED ("/proc/%ld/setgroups not found\n", child_pid);
-+ }
-+
-+ xwrite (fd, str, str_len);
-+ xclose(fd);
-+}
-+
-+static char child_stack[1024 * 1024];
-+
-+int
-+do_test (void)
-+{
-+ base = support_create_and_chdir_toolong_temp_directory (BASENAME);
-+
-+ xmkdir (MOUNT_NAME, S_IRWXU);
-+ atexit (do_cleanup);
-+
-+ TEST_VERIFY_EXIT (socketpair (AF_UNIX, SOCK_STREAM, 0, sockfd) == 0);
-+ pid_t child_pid = xclone (child_func, NULL, child_stack,
-+ sizeof (child_stack),
-+ CLONE_NEWUSER | CLONE_NEWNS | SIGCHLD);
-+
-+ xclose (sockfd[1]);
-+ const int sock = sockfd[0];
-+
-+ char map_path[sizeof ("/proc//uid_map") + INT_STRLEN_BOUND (long)];
-+ char map_buf[sizeof ("0 1") + INT_STRLEN_BOUND (long)];
-+
-+ snprintf (map_path, sizeof (map_path), "/proc/%ld/uid_map",
-+ (long) child_pid);
-+ snprintf (map_buf, sizeof (map_buf), "0 %ld 1", (long) getuid());
-+ update_map (map_buf, map_path);
-+
-+ proc_setgroups_write ((long) child_pid, "deny");
-+ snprintf (map_path, sizeof (map_path), "/proc/%ld/gid_map",
-+ (long) child_pid);
-+ snprintf (map_buf, sizeof (map_buf), "0 %ld 1", (long) getgid());
-+ update_map (map_buf, map_path);
-+
-+ TEST_VERIFY_EXIT (send (sock, "1", 1, MSG_NOSIGNAL) == 1);
-+ const int fd = recv_fd (sock);
-+ TEST_VERIFY_EXIT (fd >= 0);
-+ TEST_VERIFY_EXIT (fchdir (fd) == 0);
-+
-+ static char buf[2 * 10 + 1];
-+ memset (buf, 'A', sizeof (buf));
-+
-+ /* Finally, call getcwd and check if it resulted in a buffer underflow. */
-+ char * cwd = getcwd (buf + sizeof (buf) / 2, 1);
-+ TEST_VERIFY (cwd == NULL);
-+ TEST_VERIFY (errno == ERANGE);
-+
-+ for (int i = 0; i < sizeof (buf); i++)
-+ if (buf[i] != 'A')
-+ {
-+ printf ("buf[%d] = %02x\n", i, (unsigned int) buf[i]);
-+ support_record_failure ();
-+ }
-+
-+ TEST_VERIFY_EXIT (send (sock, "a", 1, MSG_NOSIGNAL) == 1);
-+ xclose (sock);
-+ TEST_VERIFY_EXIT (xwaitpid (child_pid, NULL, 0) == child_pid);
-+
-+ return 0;
-+}
-+
-+#define CLEANUP_HANDLER do_cleanup
-+#include <support/test-driver.c>
---
-2.27.0
-
-
generated by cgit v1.2.3-80-g2a13 (git 2.46.2) at 2024-10-06 14:23:58 +0000