e2fsprogs: Fix CVE-2022-1304

[openwrt/openwrt.git] / tools / e2fsprogs / patches / 004-CVE-2022-1304-libext2fs-add-sanity-check-to-extent-manipulation.patch

diff --git a/tools/e2fsprogs/patches/004-CVE-2022-1304-libext2fs-add-sanity-check-to-extent-manipulation.patch b/tools/e2fsprogs/patches/004-CVE-2022-1304-libext2fs-add-sanity-check-to-extent-manipulation.patch
new file mode 100644 (file)
index 0000000..e5a7616
--- /dev/null
+++ b/tools/e2fsprogs/patches/004-CVE-2022-1304-libext2fs-add-sanity-check-to-extent-manipulation.patch
@@ -0,0 +1,50 @@
+From ab51d587bb9b229b1fade1afd02e1574c1ba5c76 Mon Sep 17 00:00:00 2001
+From: Lukas Czerner <lczerner@redhat.com>
+Date: Thu, 21 Apr 2022 19:31:48 +0200
+Subject: libext2fs: add sanity check to extent manipulation
+
+It is possible to have a corrupted extent tree in such a way that a leaf
+node contains zero extents in it. Currently if that happens and we try
+to traverse the tree we can end up accessing wrong data, or possibly
+even uninitialized memory. Make sure we don't do that.
+
+Additionally make sure that we have a sane number of bytes passed to
+memmove() in ext2fs_extent_delete().
+
+Note that e2fsck is currently unable to spot and fix such corruption in
+pass1.
+
+Signed-off-by: Lukas Czerner <lczerner@redhat.com>
+Reported-by: Nils Bars <nils_bars@t-online.de>
+Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=2068113
+Addresses: CVE-2022-1304
+Addresses-Debian-Bug: #1010263
+Signed-off-by: Theodore Ts'o <tytso@mit.edu>
+---
+ lib/ext2fs/extent.c | 8 ++++++++
+ 1 file changed, 8 insertions(+)
+
+--- a/lib/ext2fs/extent.c
++++ b/lib/ext2fs/extent.c
+@@ -495,6 +495,10 @@ retry:
+                       ext2fs_le16_to_cpu(eh->eh_entries);
+               newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max);
+ 
++              /* Make sure there is at least one extent present */
++              if (newpath->left <= 0)
++                      return EXT2_ET_EXTENT_NO_DOWN;
++
+               if (path->left > 0) {
+                       ix++;
+                       newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block);
+@@ -1630,6 +1634,10 @@ errcode_t ext2fs_extent_delete(ext2_exte
+ 
+       cp = path->curr;
+ 
++      /* Sanity check before memmove() */
++      if (path->left < 0)
++              return EXT2_ET_EXTENT_LEAF_BAD;
++
+       if (path->left) {
+               memmove(cp, cp + sizeof(struct ext3_extent_idx),
+                       path->left * sizeof(struct ext3_extent_idx));