diff options
Diffstat (limited to '')
| -rw-r--r-- | debian/patches/CVE-2023-38408-2.patch | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/debian/patches/CVE-2023-38408-2.patch b/debian/patches/CVE-2023-38408-2.patch new file mode 100644 index 0000000..7ee3c13 --- /dev/null +++ b/debian/patches/CVE-2023-38408-2.patch @@ -0,0 +1,171 @@ +From fb685ebb9f8391ab2836715c9c347ee50a0c9f48 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: backport, https://anongit.mindrot.org/openssh.git/commit/?id=29ef8a04866ca14688d5b7fed7b8b9deab851f77 +Last-Update: 2023-09-17 + +Patch-Name: CVE-2023-38408-2.patch +--- + misc.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++ + misc.h | 1 + + ssh-pkcs11.c | 4 +++ + ssh-sk.c | 6 ++-- + 4 files changed, 88 insertions(+), 2 deletions(-) + +diff --git a/misc.c b/misc.c +index c75a795c2..c6e9e71a3 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> +@@ -2463,3 +2467,78 @@ ssh_signal(int signum, sshsig_t handler) + } + return osa.sa_handler; + } ++ ++/* ++ * 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("%s: nlist failed for %s", __func__, path); ++ goto out; ++ } ++ if (r != 0 || nl[0].n_value == 0 || nl[0].n_type == 0) { ++ error("%s: library %s does not contain symbol %s", ++ __func__, 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("%s: open %s: %s", __func__, path, strerror(errno)); ++ return -1; ++ } ++ if (fstat(fd, &st) != 0) { ++ error("%s: fstat %s: %s", __func__, path, strerror(errno)); ++ goto out; ++ } ++ if (!S_ISREG(st.st_mode)) { ++ error("%s: %s is not a regular file", __func__, path); ++ goto out; ++ } ++ if (st.st_size < 0 || ++ (size_t)st.st_size < strlen(s) || ++ st.st_size >= INT_MAX/2) { ++ error("%s: %s bad size %lld", ++ __func__, 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("%s: mmap %s: %s", __func__, path, strerror(errno)); ++ goto out; ++ } ++ if (memmem(m, sz, s, strlen(s)) == NULL) { ++ error("%s: %s does not contain expected string %s", ++ __func__, 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 b34c798e7..eb30bb454 100644 +--- a/misc.h ++++ b/misc.h +@@ -90,6 +90,7 @@ const char *atoi_err(const char *, int *); + int parse_absolute_time(const char *, uint64_t *); + void format_absolute_time(uint64_t, char *, size_t); + int path_absolute(const char *); ++int lib_contains_symbol(const char *, const char *); + + void sock_set_v6only(int); + +diff --git a/ssh-pkcs11.c b/ssh-pkcs11.c +index d864051c4..df4d53626 100644 +--- a/ssh-pkcs11.c ++++ b/ssh-pkcs11.c +@@ -1514,6 +1514,10 @@ pkcs11_register_provider(char *provider_id, char *pin, + __func__, 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 1455df635..76fee8af2 100644 +--- a/ssh-sk.c ++++ b/ssh-sk.c +@@ -123,10 +123,12 @@ sshsk_open(const char *path) + #endif + return ret; + } +- 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", |