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-rw-r--r--meta/recipes-core/glib-2.0/glib-2.0/CVE-2023-32643.patch155
1 files changed, 155 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..b5cb4273b6
--- /dev/null
+++ b/meta/recipes-core/glib-2.0/glib-2.0/CVE-2023-32643.patch
@@ -0,0 +1,155 @@
+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 [https://gitlab.gnome.org/GNOME/glib/-/commit/78da5faccb3e065116b75b3ff87ff55381da6c76]
+
+Signed-off-by: Soumya Sambu <soumya.sambu@windriver.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 3d6e7b8..5abb87e 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 43091f2..ab0361a 100644
+--- a/glib/tests/gvariant.c
++++ b/glib/tests/gvariant.c
+@@ -5416,6 +5416,67 @@ 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.
+ *
+@@ -5663,6 +5724,8 @@ 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",
+--
+2.40.0