flatpak/CVE-2023-28101-1.patch
starlet-dx c06772b78d Fix CVE-2023-28100 and CVE-2023-28101 and Fix several memory leaks
(cherry picked from commit 6fe17b7f232e7c9530c41cff1c634d3cbad5ef28)
2024-03-29 09:00:50 +08:00

321 lines
10 KiB
Diff

From acd627a2fabe9856947399044dbf7aa79247c75b Mon Sep 17 00:00:00 2001
From: Ryan Gonzalez <ryan.gonzalez@collabora.com>
Date: Sat, 4 Mar 2023 16:23:37 -0600
Subject: [PATCH] Ensure special characters in permissions and metadata are
escaped
This prevents someone from placing special characters in order to
manipulate the appearance of the permissions list.
CVE-2023-28101, GHSA-h43h-fwqx-mpp8
Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>
---
app/flatpak-builtins-info.c | 8 +++-
app/flatpak-builtins-remote-info.c | 5 +-
app/flatpak-cli-transaction.c | 12 +++--
common/flatpak-utils-private.h | 11 +++++
common/flatpak-utils.c | 77 ++++++++++++++++++++++++++++++
tests/make-test-app.sh | 8 ++++
tests/test-info.sh | 14 ++++--
tests/testcommon.c | 39 +++++++++++++++
8 files changed, 164 insertions(+), 10 deletions(-)
diff --git a/app/flatpak-builtins-info.c b/app/flatpak-builtins-info.c
index c13d2d89eb..35d49c446a 100644
--- a/app/flatpak-builtins-info.c
+++ b/app/flatpak-builtins-info.c
@@ -400,7 +400,9 @@ flatpak_builtin_info (int argc, char **argv, GCancellable *cancellable, GError *
if (!g_file_load_contents (file, cancellable, &data, &data_size, NULL, error))
return FALSE;
- g_print ("%s", data);
+ flatpak_print_escaped_string (data,
+ FLATPAK_ESCAPE_ALLOW_NEWLINES
+ | FLATPAK_ESCAPE_DO_NOT_QUOTE);
}
if (opt_show_permissions || opt_file_access)
@@ -421,7 +423,9 @@ flatpak_builtin_info (int argc, char **argv, GCancellable *cancellable, GError *
if (contents == NULL)
return FALSE;
- g_print ("%s", contents);
+ flatpak_print_escaped_string (contents,
+ FLATPAK_ESCAPE_ALLOW_NEWLINES
+ | FLATPAK_ESCAPE_DO_NOT_QUOTE);
}
if (opt_file_access)
diff --git a/app/flatpak-builtins-remote-info.c b/app/flatpak-builtins-remote-info.c
index 20705a97ca..0ab05b7ca4 100644
--- a/app/flatpak-builtins-remote-info.c
+++ b/app/flatpak-builtins-remote-info.c
@@ -441,7 +441,10 @@ flatpak_builtin_remote_info (int argc, char **argv, GCancellable *cancellable, G
if (opt_show_metadata)
{
- g_print ("%s", xa_metadata ? xa_metadata : "");
+ if (xa_metadata != NULL)
+ flatpak_print_escaped_string (xa_metadata,
+ FLATPAK_ESCAPE_ALLOW_NEWLINES
+ | FLATPAK_ESCAPE_DO_NOT_QUOTE);
if (xa_metadata == NULL || !g_str_has_suffix (xa_metadata, "\n"))
g_print ("\n");
}
diff --git a/app/flatpak-cli-transaction.c b/app/flatpak-cli-transaction.c
index a258f905c4..b915bedd04 100644
--- a/app/flatpak-cli-transaction.c
+++ b/app/flatpak-cli-transaction.c
@@ -894,12 +894,16 @@ print_perm_line (int idx,
int cols)
{
g_autoptr(GString) res = g_string_new (NULL);
+ g_autofree char *escaped_first_perm = NULL;
int i;
- g_string_append_printf (res, " [%d] %s", idx, (char *) items->pdata[0]);
+ escaped_first_perm = flatpak_escape_string (items->pdata[0], FLATPAK_ESCAPE_DEFAULT);
+ g_string_append_printf (res, " [%d] %s", idx, escaped_first_perm);
for (i = 1; i < items->len; i++)
{
+ g_autofree char *escaped = flatpak_escape_string (items->pdata[i],
+ FLATPAK_ESCAPE_DEFAULT);
char *p;
int len;
@@ -908,10 +912,10 @@ print_perm_line (int idx,
p = res->str;
len = (res->str + strlen (res->str)) - p;
- if (len + strlen ((char *) items->pdata[i]) + 2 >= cols)
- g_string_append_printf (res, ",\n %s", (char *) items->pdata[i]);
+ if (len + strlen (escaped) + 2 >= cols)
+ g_string_append_printf (res, ",\n %s", escaped);
else
- g_string_append_printf (res, ", %s", (char *) items->pdata[i]);
+ g_string_append_printf (res, ", %s", escaped);
}
g_print ("%s\n", res->str);
diff --git a/common/flatpak-utils-private.h b/common/flatpak-utils-private.h
index 1a92154706..c1282641f9 100644
--- a/common/flatpak-utils-private.h
+++ b/common/flatpak-utils-private.h
@@ -902,6 +902,17 @@ null_safe_g_ptr_array_unref (gpointer data)
g_clear_pointer (&data, g_ptr_array_unref);
}
+typedef enum {
+ FLATPAK_ESCAPE_DEFAULT = 0,
+ FLATPAK_ESCAPE_ALLOW_NEWLINES = 1 << 0,
+ FLATPAK_ESCAPE_DO_NOT_QUOTE = 1 << 1,
+} FlatpakEscapeFlags;
+
+char * flatpak_escape_string (const char *s,
+ FlatpakEscapeFlags flags);
+void flatpak_print_escaped_string (const char *s,
+ FlatpakEscapeFlags flags);
+
#define FLATPAK_MESSAGE_ID "c7b39b1e006b464599465e105b361485"
#endif /* __FLATPAK_UTILS_H__ */
diff --git a/common/flatpak-utils.c b/common/flatpak-utils.c
index 3a5adb82ee..0b91ae3f91 100644
--- a/common/flatpak-utils.c
+++ b/common/flatpak-utils.c
@@ -8613,4 +8613,81 @@ flatpak_dconf_path_is_similar (const char *path1,
return (path1[i1] == '\0');
}
+static gboolean
+is_char_safe (gunichar c)
+{
+ return g_unichar_isgraph (c) || c == ' ';
+}
+
+static gboolean
+should_hex_escape (gunichar c,
+ FlatpakEscapeFlags flags)
+{
+ if ((flags & FLATPAK_ESCAPE_ALLOW_NEWLINES) && c == '\n')
+ return FALSE;
+ return !is_char_safe (c);
+}
+
+static void
+append_hex_escaped_character (GString *result,
+ gunichar c)
+{
+ if (c <= 0xFF)
+ g_string_append_printf (result, "\\x%02X", c);
+ else if (c <= 0xFFFF)
+ g_string_append_printf (result, "\\u%04X", c);
+ else
+ g_string_append_printf (result, "\\U%08X", c);
+}
+
+char *
+flatpak_escape_string (const char *s,
+ FlatpakEscapeFlags flags)
+{
+ g_autoptr(GString) res = g_string_new ("");
+ gboolean did_escape = FALSE;
+
+ while (*s)
+ {
+ gunichar c = g_utf8_get_char_validated (s, -1);
+ if (c == (gunichar)-2 || c == (gunichar)-1)
+ {
+ /* Need to convert to unsigned first, to avoid negative chars becoming
+ huge gunichars. */
+ append_hex_escaped_character (res, (unsigned char)*s++);
+ did_escape = TRUE;
+ continue;
+ }
+ else if (should_hex_escape (c, flags))
+ {
+ append_hex_escaped_character (res, c);
+ did_escape = TRUE;
+ }
+ else if (c == '\\' || (!(flags & FLATPAK_ESCAPE_DO_NOT_QUOTE) && c == '\''))
+ {
+ g_string_append_printf (res, "\\%c", (char) c);
+ did_escape = TRUE;
+ }
+ else
+ g_string_append_unichar (res, c);
+
+ s = g_utf8_find_next_char (s, NULL);
+ }
+
+ if (did_escape && !(flags & FLATPAK_ESCAPE_DO_NOT_QUOTE))
+ {
+ g_string_prepend_c (res, '\'');
+ g_string_append_c (res, '\'');
+ }
+
+ return g_string_free (g_steal_pointer (&res), FALSE);
+}
+
+void
+flatpak_print_escaped_string (const char *s,
+ FlatpakEscapeFlags flags)
+{
+ g_autofree char *escaped = flatpak_escape_string (s, flags);
+ g_print ("%s", escaped);
+}
diff --git a/tests/make-test-app.sh b/tests/make-test-app.sh
index 731160535c..125e97f6b5 100755
--- a/tests/make-test-app.sh
+++ b/tests/make-test-app.sh
@@ -40,6 +40,14 @@ required-flatpak=$REQUIRED_VERSION
EOF
fi
+if [ x${INCLUDE_SPECIAL_CHARACTER-} != x ]; then
+TAB=$'\t'
+cat >> ${DIR}/metadata <<EOF
+[Environment]
+A=x${TAB}y
+EOF
+fi
+
cat >> ${DIR}/metadata <<EOF
[Extension $APP_ID.Locale]
directory=share/runtime/locale
diff --git a/tests/test-info.sh b/tests/test-info.sh
index 4a247bdb48..2158c11b10 100644
--- a/tests/test-info.sh
+++ b/tests/test-info.sh
@@ -6,9 +6,9 @@ set -euo pipefail
skip_revokefs_without_fuse
-echo "1..7"
+echo "1..8"
-setup_repo
+INCLUDE_SPECIAL_CHARACTER=1 setup_repo
install_repo
COMMIT=`${FLATPAK} ${U} info --show-commit org.test.Hello`
@@ -19,9 +19,17 @@ assert_file_has_content info "^app/org\.test\.Hello/$(flatpak --default-arch)/ma
ok "info -rcos"
+${FLATPAK} info --show-metadata org.test.Hello > info
+
+# CVE-2023-28101
+assert_file_has_content info "name=org\.test\.Hello"
+assert_file_has_content info "^A=x\\\\x09y"
+
+ok "info --show-metadata"
+
${FLATPAK} info --show-permissions org.test.Hello > info
-assert_file_empty info
+assert_file_has_content info "^A=x\\\\x09y"
ok "info --show-permissions"
diff --git a/tests/testcommon.c b/tests/testcommon.c
index 1d217c072a..daae5e4aac 100644
--- a/tests/testcommon.c
+++ b/tests/testcommon.c
@@ -1557,6 +1557,44 @@ test_dconf_paths (void)
}
}
+typedef struct {
+ const char *in;
+ FlatpakEscapeFlags flags;
+ const char *out;
+} EscapeData;
+
+static EscapeData escapes[] = {
+ {"abc def", FLATPAK_ESCAPE_DEFAULT, "abc def"},
+ {"やあ", FLATPAK_ESCAPE_DEFAULT, "やあ"},
+ {"\033[;1m", FLATPAK_ESCAPE_DEFAULT, "'\\x1B[;1m'"},
+ // non-printable U+061C
+ {"\u061C", FLATPAK_ESCAPE_DEFAULT, "'\\u061C'"},
+ // non-printable U+1343F
+ {"\xF0\x93\x90\xBF", FLATPAK_ESCAPE_DEFAULT, "'\\U0001343F'"},
+ // invalid utf-8
+ {"\xD8\1", FLATPAK_ESCAPE_DEFAULT, "'\\xD8\\x01'"},
+ {"\b \n abc ' \\", FLATPAK_ESCAPE_DEFAULT, "'\\x08 \\x0A abc \\' \\\\'"},
+ {"\b \n abc ' \\", FLATPAK_ESCAPE_DO_NOT_QUOTE, "\\x08 \\x0A abc ' \\\\"},
+ {"abc\tdef\n\033[;1m ghi\b", FLATPAK_ESCAPE_ALLOW_NEWLINES | FLATPAK_ESCAPE_DO_NOT_QUOTE,
+ "abc\\x09def\n\\x1B[;1m ghi\\x08"},
+};
+
+/* CVE-2023-28101 */
+static void
+test_string_escape (void)
+{
+ gsize idx;
+
+ for (idx = 0; idx < G_N_ELEMENTS (escapes); idx++)
+ {
+ EscapeData *data = &escapes[idx];
+ g_autofree char *ret = NULL;
+
+ ret = flatpak_escape_string (data->in, data->flags);
+ g_assert_cmpstr (ret, ==, data->out);
+ }
+}
+
int
main (int argc, char *argv[])
{
@@ -1585,6 +1623,7 @@ main (int argc, char *argv[])
g_test_add_func ("/common/dconf-app-id", test_dconf_app_id);
g_test_add_func ("/common/dconf-paths", test_dconf_paths);
g_test_add_func ("/common/decompose-ref", test_decompose);
+ g_test_add_func ("/common/string-escape", test_string_escape);
g_test_add_func ("/app/looks-like-branch", test_looks_like_branch);
g_test_add_func ("/app/columns", test_columns);