1 files changed, 154 insertions, 0 deletions

diff --git a/meta/recipes-core/glib-2.0/glib-2.0/CVE-2023-32643.patch b/meta/recipes-core/glib-2.0/glib-2.0/CVE-2023-32643.patch
new file mode 100644
index 0000000000..9c0867bf5f
--- /dev/null
+++ b/meta/recipes-core/glib-2.0/glib-2.0/CVE-2023-32643.patch
@@ -0,0 +1,154 @@
+From 78da5faccb3e065116b75b3ff87ff55381da6c76 Mon Sep 17 00:00:00 2001
+From: Philip Withnall <pwithnall@endlessos.org>
+Date: Thu, 17 Aug 2023 11:24:43 +0000
+Subject: [PATCH] gvariant: Check offset table doesn't fall outside variant
+ bounds
+
+When dereferencing the first entry in the offset table for a tuple,
+check that it doesn’t fall outside the bounds of the variant first.
+
+This prevents an out-of-bounds read from some non-normal tuples.
+
+This bug was introduced in commit 73d0aa81c2575a5c9ae77d.
+
+Includes a unit test, although the test will likely only catch the
+original bug if run with asan enabled.
+
+Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
+
+Fixes: #2840
+oss-fuzz#54302
+
+CVE: CVE-2023-32643
+Upstream-Status: Backport from [https://gitlab.gnome.org/GNOME/glib/-/commit/78da5faccb3e065116b75b3ff87ff55381da6c76]
+Signed-off-by: Siddharth Doshi <sdoshi@mvista.com>
+---
+ glib/gvariant-serialiser.c | 12 ++++++--
+ glib/tests/gvariant.c      | 63 ++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 72 insertions(+), 3 deletions(-)
+
+diff --git a/glib/gvariant-serialiser.c b/glib/gvariant-serialiser.c
+index 5aa2cbc..4e50ed7 100644
+--- a/glib/gvariant-serialiser.c
++++ b/glib/gvariant-serialiser.c
+@@ -979,7 +979,8 @@ gvs_tuple_get_member_bounds (GVariantSerialised  value,
+ 
+   member_info = g_variant_type_info_member_info (value.type_info, index_);
+ 
+-  if (member_info->i + 1)
++  if (member_info->i + 1 &&
++      offset_size * (member_info->i + 1) <= value.size)
+     member_start = gvs_read_unaligned_le (value.data + value.size -
+                                           offset_size * (member_info->i + 1),
+                                           offset_size);
+@@ -990,7 +991,8 @@ gvs_tuple_get_member_bounds (GVariantSerialised  value,
+   member_start &= member_info->b;
+   member_start |= member_info->c;
+ 
+-  if (member_info->ending_type == G_VARIANT_MEMBER_ENDING_LAST)
++  if (member_info->ending_type == G_VARIANT_MEMBER_ENDING_LAST &&
++      offset_size * (member_info->i + 1) <= value.size)
+     member_end = value.size - offset_size * (member_info->i + 1);
+ 
+   else if (member_info->ending_type == G_VARIANT_MEMBER_ENDING_FIXED)
+@@ -1001,11 +1003,15 @@ gvs_tuple_get_member_bounds (GVariantSerialised  value,
+       member_end = member_start + fixed_size;
+     }
+ 
+-  else /* G_VARIANT_MEMBER_ENDING_OFFSET */
++  else if (member_info->ending_type == G_VARIANT_MEMBER_ENDING_OFFSET &&
++           offset_size * (member_info->i + 2) <= value.size)
+     member_end = gvs_read_unaligned_le (value.data + value.size -
+                                         offset_size * (member_info->i + 2),
+                                         offset_size);
+ 
++  else  /* invalid */
++    member_end = G_MAXSIZE;
++
+   if (out_member_start != NULL)
+     *out_member_start = member_start;
+   if (out_member_end != NULL)
+diff --git a/glib/tests/gvariant.c b/glib/tests/gvariant.c
+index 679dd40..2eca8be 100644
+--- a/glib/tests/gvariant.c
++++ b/glib/tests/gvariant.c
+@@ -5432,6 +5432,67 @@ test_normal_checking_tuple_offsets4 (void)
+   g_variant_unref (variant);
+ }
+ 
++/* This is a regression test that dereferencing the first element in the offset
++ * table doesn’t dereference memory before the start of the GVariant. The first
++ * element in the offset table gives the offset of the final member in the
++ * tuple (the offset table is stored in reverse), and the position of this final
++ * member is needed to check that none of the tuple members overlap with the
++ * offset table
++ *
++ * See https://gitlab.gnome.org/GNOME/glib/-/issues/2840 */
++static void
++test_normal_checking_tuple_offsets5 (void)
++{
++  /* A tuple of type (sss) in normal form would have an offset table with two
++   * entries:
++   *  - The first entry (lowest index in the table) gives the offset of the
++   *    third `s` in the tuple, as the offset table is reversed compared to the
++   *    tuple members.
++   *  - The second entry (highest index in the table) gives the offset of the
++   *    second `s` in the tuple.
++   *  - The offset of the first `s` in the tuple is always 0.
++   *
++   * See §2.5.4 (Structures) of the GVariant specification for details, noting
++   * that the table is only layed out this way because all three members of the
++   * tuple have non-fixed sizes.
++   *
++   * It’s not clear whether the 0xaa data of this variant is part of the strings
++   * in the tuple, or part of the offset table. It doesn’t really matter. This
++   * is a regression test to check that the code to validate the offset table
++   * doesn’t unconditionally try to access the first entry in the offset table
++   * by subtracting the table size from the end of the GVariant data.
++   *
++   * In this non-normal case, that would result in an address off the start of
++   * the GVariant data, and an out-of-bounds read, because the GVariant is one
++   * byte long, but the offset table is calculated as two bytes long (with 1B
++   * sized entries) from the tuple’s type.
++   */
++  const GVariantType *data_type = G_VARIANT_TYPE ("(sss)");
++  const guint8 data[] = { 0xaa };
++  gsize size = sizeof (data);
++  GVariant *variant = NULL;
++  GVariant *normal_variant = NULL;
++  GVariant *expected = NULL;
++
++  g_test_bug ("https://gitlab.gnome.org/GNOME/glib/-/issues/2840");
++
++  variant = g_variant_new_from_data (data_type, data, size, FALSE, NULL, NULL);
++  g_assert_nonnull (variant);
++
++  g_assert_false (g_variant_is_normal_form (variant));
++
++  normal_variant = g_variant_get_normal_form (variant);
++  g_assert_nonnull (normal_variant);
++
++  expected = g_variant_new_parsed ("('', '', '')");
++  g_assert_cmpvariant (expected, variant);
++  g_assert_cmpvariant (expected, normal_variant);
++
++  g_variant_unref (expected);
++  g_variant_unref (normal_variant);
++  g_variant_unref (variant);
++}
++
+ /* Test that an otherwise-valid serialised GVariant is considered non-normal if
+  * its offset table entries are too wide.
+  *
+@@ -5680,6 +5741,8 @@ main (int argc, char **argv)
+                    test_normal_checking_tuple_offsets3);
+   g_test_add_func ("/gvariant/normal-checking/tuple-offsets4",
+                    test_normal_checking_tuple_offsets4);
++  g_test_add_func ("/gvariant/normal-checking/tuple-offsets5",
++                   test_normal_checking_tuple_offsets5);
+   g_test_add_func ("/gvariant/normal-checking/tuple-offsets/minimal-sized",
+                    test_normal_checking_tuple_offsets_minimal_sized);
+   g_test_add_func ("/gvariant/normal-checking/empty-object-path",
+-- 
+2.24.4
+