diff options
Diffstat (limited to 'debian/patches/CVE-2023-38408-3.patch')
| -rw-r--r-- | debian/patches/CVE-2023-38408-3.patch | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/debian/patches/CVE-2023-38408-3.patch b/debian/patches/CVE-2023-38408-3.patch new file mode 100644 index 0000000..6089222 --- /dev/null +++ b/debian/patches/CVE-2023-38408-3.patch @@ -0,0 +1,174 @@ +From 29c7785a3673101b3af8f6f712795fa128e52ddd Mon Sep 17 00:00:00 2001 +From: "djm@openbsd.org" <djm@openbsd.org> +Date: Wed, 19 Jul 2023 14:02:27 +0000 +Subject: upstream: Ensure FIDO/PKCS11 libraries contain expected symbols + +This checks via nlist(3) that candidate provider libraries contain one +of the symbols that we will require prior to dlopen(), which can cause +a number of side effects, including execution of constructors. + +Feedback deraadt; ok markus + +OpenBSD-Commit-ID: 1508a5fbd74e329e69a55b56c453c292029aefbe + +Origin: upstream, https://anongit.mindrot.org/openssh.git/commit/?id=29ef8a04866ca14688d5b7fed7b8b9deab851f77 +Last-Update: 2023-09-17 + +Patch-Name: CVE-2023-38408-3.patch +--- + misc.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++ + misc.h | 1 + + ssh-pkcs11.c | 4 +++ + ssh-sk.c | 8 +++--- + 4 files changed, 86 insertions(+), 3 deletions(-) + +diff --git a/misc.c b/misc.c +index 2268d8875..36e72f5b5 100644 +--- a/misc.c ++++ b/misc.c +@@ -22,6 +22,7 @@ + + #include <sys/types.h> + #include <sys/ioctl.h> ++#include <sys/mman.h> + #include <sys/socket.h> + #include <sys/stat.h> + #include <sys/time.h> +@@ -35,6 +36,9 @@ + #ifdef HAVE_POLL_H + #include <poll.h> + #endif ++#ifdef HAVE_NLIST_H ++#include <nlist.h> ++#endif + #include <signal.h> + #include <stdarg.h> + #include <stdio.h> +@@ -2962,3 +2966,75 @@ ptimeout_isset(struct timespec *pt) + { + return pt->tv_sec != -1; + } ++ ++/* ++ * Returns zero if the library at 'path' contains symbol 's', nonzero ++ * otherwise. ++ */ ++int ++lib_contains_symbol(const char *path, const char *s) ++{ ++#ifdef HAVE_NLIST_H ++ struct nlist nl[2]; ++ int ret = -1, r; ++ ++ memset(nl, 0, sizeof(nl)); ++ nl[0].n_name = xstrdup(s); ++ nl[1].n_name = NULL; ++ if ((r = nlist(path, nl)) == -1) { ++ error_f("nlist failed for %s", path); ++ goto out; ++ } ++ if (r != 0 || nl[0].n_value == 0 || nl[0].n_type == 0) { ++ error_f("library %s does not contain symbol %s", path, s); ++ goto out; ++ } ++ /* success */ ++ ret = 0; ++ out: ++ free(nl[0].n_name); ++ return ret; ++#else /* HAVE_NLIST_H */ ++ int fd, ret = -1; ++ struct stat st; ++ void *m = NULL; ++ size_t sz = 0; ++ ++ memset(&st, 0, sizeof(st)); ++ if ((fd = open(path, O_RDONLY)) < 0) { ++ error_f("open %s: %s", path, strerror(errno)); ++ return -1; ++ } ++ if (fstat(fd, &st) != 0) { ++ error_f("fstat %s: %s", path, strerror(errno)); ++ goto out; ++ } ++ if (!S_ISREG(st.st_mode)) { ++ error_f("%s is not a regular file", path); ++ goto out; ++ } ++ if (st.st_size < 0 || ++ (size_t)st.st_size < strlen(s) || ++ st.st_size >= INT_MAX/2) { ++ error_f("%s bad size %lld", path, (long long)st.st_size); ++ goto out; ++ } ++ sz = (size_t)st.st_size; ++ if ((m = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, fd, 0)) == MAP_FAILED || ++ m == NULL) { ++ error_f("mmap %s: %s", path, strerror(errno)); ++ goto out; ++ } ++ if (memmem(m, sz, s, strlen(s)) == NULL) { ++ error_f("%s does not contain expected string %s", path, s); ++ goto out; ++ } ++ /* success */ ++ ret = 0; ++ out: ++ if (m != NULL && m != MAP_FAILED) ++ munmap(m, sz); ++ close(fd); ++ return ret; ++#endif /* HAVE_NLIST_H */ ++} +diff --git a/misc.h b/misc.h +index 31b6557c6..1a49e7cec 100644 +--- a/misc.h ++++ b/misc.h +@@ -96,6 +96,7 @@ int parse_absolute_time(const char *, uint64_t *); + void format_absolute_time(uint64_t, char *, size_t); + int path_absolute(const char *); + int stdfd_devnull(int, int, int); ++int lib_contains_symbol(const char *, const char *); + + void sock_set_v6only(int); + +diff --git a/ssh-pkcs11.c b/ssh-pkcs11.c +index 9e48c134e..0aef37934 100644 +--- a/ssh-pkcs11.c ++++ b/ssh-pkcs11.c +@@ -1532,6 +1532,10 @@ pkcs11_register_provider(char *provider_id, char *pin, + debug_f("provider already registered: %s", provider_id); + goto fail; + } ++ if (lib_contains_symbol(provider_id, "C_GetFunctionList") != 0) { ++ error("provider %s is not a PKCS11 library", provider_id); ++ goto fail; ++ } + /* open shared pkcs11-library */ + if ((handle = dlopen(provider_id, RTLD_NOW)) == NULL) { + error("dlopen %s failed: %s", provider_id, dlerror()); +diff --git a/ssh-sk.c b/ssh-sk.c +index fbeb39320..d1c18803f 100644 +--- a/ssh-sk.c ++++ b/ssh-sk.c +@@ -1,4 +1,4 @@ +-/* $OpenBSD: ssh-sk.c,v 1.39 2022/07/20 03:29:14 djm Exp $ */ ++/* $OpenBSD: ssh-sk.c,v 1.40 2023/07/19 14:02:27 djm Exp $ */ + /* + * Copyright (c) 2019 Google LLC + * +@@ -133,10 +133,12 @@ sshsk_open(const char *path) + goto fail; + #endif + } +- if ((ret->dlhandle = dlopen(path, RTLD_NOW)) == NULL) { +- error("Provider \"%s\" dlopen failed: %s", path, dlerror()); ++ if (lib_contains_symbol(path, "sk_api_version") != 0) { ++ error("provider %s is not an OpenSSH FIDO library", path); + goto fail; + } ++ if ((ret->dlhandle = dlopen(path, RTLD_NOW)) == NULL) ++ fatal("Provider \"%s\" dlopen failed: %s", path, dlerror()); + if ((ret->sk_api_version = dlsym(ret->dlhandle, + "sk_api_version")) == NULL) { + error("Provider \"%s\" dlsym(sk_api_version) failed: %s", |