4.14-stable patches

added patches:
	ext4-add-validity-checks-for-bitmap-block-numbers.patch

diff --git a/queue-4.14/ext4-add-validity-checks-for-bitmap-block-numbers.patch b/queue-4.14/ext4-add-validity-checks-for-bitmap-block-numbers.patch
new file mode 100644 (file)
index 0000000..f4cd44b
--- /dev/null
+++ b/queue-4.14/ext4-add-validity-checks-for-bitmap-block-numbers.patch
@@ -0,0 +1,101 @@
+From 7dac4a1726a9c64a517d595c40e95e2d0d135f6f Mon Sep 17 00:00:00 2001
+From: Theodore Ts'o <tytso@mit.edu>
+Date: Mon, 26 Mar 2018 23:54:10 -0400
+Subject: ext4: add validity checks for bitmap block numbers
+
+From: Theodore Ts'o <tytso@mit.edu>
+
+commit 7dac4a1726a9c64a517d595c40e95e2d0d135f6f upstream.
+
+An privileged attacker can cause a crash by mounting a crafted ext4
+image which triggers a out-of-bounds read in the function
+ext4_valid_block_bitmap() in fs/ext4/balloc.c.
+
+This issue has been assigned CVE-2018-1093.
+
+BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199181
+BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1560782
+Reported-by: Wen Xu <wen.xu@gatech.edu>
+Signed-off-by: Theodore Ts'o <tytso@mit.edu>
+Cc: stable@vger.kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/ext4/balloc.c |   16 ++++++++++++++--
+ fs/ext4/ialloc.c |    7 +++++++
+ 2 files changed, 21 insertions(+), 2 deletions(-)
+
+--- a/fs/ext4/balloc.c
++++ b/fs/ext4/balloc.c
+@@ -338,20 +338,25 @@ static ext4_fsblk_t ext4_valid_block_bit
+       /* check whether block bitmap block number is set */
+       blk = ext4_block_bitmap(sb, desc);
+       offset = blk - group_first_block;
+-      if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
++      if (offset < 0 || EXT4_B2C(sbi, offset) >= sb->s_blocksize ||
++          !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
+               /* bad block bitmap */
+               return blk;
+ 
+       /* check whether the inode bitmap block number is set */
+       blk = ext4_inode_bitmap(sb, desc);
+       offset = blk - group_first_block;
+-      if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
++      if (offset < 0 || EXT4_B2C(sbi, offset) >= sb->s_blocksize ||
++          !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
+               /* bad block bitmap */
+               return blk;
+ 
+       /* check whether the inode table block number is set */
+       blk = ext4_inode_table(sb, desc);
+       offset = blk - group_first_block;
++      if (offset < 0 || EXT4_B2C(sbi, offset) >= sb->s_blocksize ||
++          EXT4_B2C(sbi, offset + sbi->s_itb_per_group) >= sb->s_blocksize)
++              return blk;
+       next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
+                       EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group),
+                       EXT4_B2C(sbi, offset));
+@@ -417,6 +422,7 @@ struct buffer_head *
+ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
+ {
+       struct ext4_group_desc *desc;
++      struct ext4_sb_info *sbi = EXT4_SB(sb);
+       struct buffer_head *bh;
+       ext4_fsblk_t bitmap_blk;
+       int err;
+@@ -425,6 +431,12 @@ ext4_read_block_bitmap_nowait(struct sup
+       if (!desc)
+               return ERR_PTR(-EFSCORRUPTED);
+       bitmap_blk = ext4_block_bitmap(sb, desc);
++      if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
++          (bitmap_blk >= ext4_blocks_count(sbi->s_es))) {
++              ext4_error(sb, "Invalid block bitmap block %llu in "
++                         "block_group %u", bitmap_blk, block_group);
++              return ERR_PTR(-EFSCORRUPTED);
++      }
+       bh = sb_getblk(sb, bitmap_blk);
+       if (unlikely(!bh)) {
+               ext4_error(sb, "Cannot get buffer for block bitmap - "
+--- a/fs/ext4/ialloc.c
++++ b/fs/ext4/ialloc.c
+@@ -122,6 +122,7 @@ static struct buffer_head *
+ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
+ {
+       struct ext4_group_desc *desc;
++      struct ext4_sb_info *sbi = EXT4_SB(sb);
+       struct buffer_head *bh = NULL;
+       ext4_fsblk_t bitmap_blk;
+       int err;
+@@ -131,6 +132,12 @@ ext4_read_inode_bitmap(struct super_bloc
+               return ERR_PTR(-EFSCORRUPTED);
+ 
+       bitmap_blk = ext4_inode_bitmap(sb, desc);
++      if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
++          (bitmap_blk >= ext4_blocks_count(sbi->s_es))) {
++              ext4_error(sb, "Invalid inode bitmap blk %llu in "
++                         "block_group %u", bitmap_blk, block_group);
++              return ERR_PTR(-EFSCORRUPTED);
++      }
+       bh = sb_getblk(sb, bitmap_blk);
+       if (unlikely(!bh)) {
+               ext4_error(sb, "Cannot read inode bitmap - "

diff --git a/queue-4.14/series b/queue-4.14/series
index d4dec00715cba5ba005de5ceec0d75d47307481d..3754981b39321efca3cc05defabc0d7407ccd9fb 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -1,3 +1,4 @@
 ext4-prevent-right-shifting-extents-beyond-ext_max_blocks.patch
 ext4-set-h_journal-if-there-is-a-failure-starting-a-reserved-handle.patch
 ext4-add-module_softdep-to-ensure-crc32c-is-included-in-the-initramfs.patch
+ext4-add-validity-checks-for-bitmap-block-numbers.patch