3.16.81-rc1 review patch. If anyone has any objections, please let me know.
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From: Ben Hutchings ben@decadent.org.uk
Based on commit 7bc04c5c2cc4 "ext4: fix use-after-free race with debug_want_extra_isize". We don't have that bug but this will make it easier to backport commit 4ea99936a163 "ext4: add more paranoia checking in ext4_expand_extra_isize handling".
Cc: Barret Rhoden brho@google.com Cc: Theodore Ts'o tytso@mit.edu Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3423,6 +3423,36 @@ int ext4_calculate_overhead(struct super return 0; }
+static void ext4_clamp_want_extra_isize(struct super_block *sb) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + struct ext4_super_block *es = sbi->s_es; + + /* determine the minimum size of new large inodes, if present */ + if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) { + sbi->s_want_extra_isize = sizeof(struct ext4_inode) - + EXT4_GOOD_OLD_INODE_SIZE; + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) { + if (sbi->s_want_extra_isize < + le16_to_cpu(es->s_want_extra_isize)) + sbi->s_want_extra_isize = + le16_to_cpu(es->s_want_extra_isize); + if (sbi->s_want_extra_isize < + le16_to_cpu(es->s_min_extra_isize)) + sbi->s_want_extra_isize = + le16_to_cpu(es->s_min_extra_isize); + } + } + /* Check if enough inode space is available */ + if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize > + sbi->s_inode_size) { + sbi->s_want_extra_isize = sizeof(struct ext4_inode) - + EXT4_GOOD_OLD_INODE_SIZE; + ext4_msg(sb, KERN_INFO, + "required extra inode space not available"); + } +}
static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb) { @@ -4245,30 +4275,7 @@ no_journal: if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY)) sb->s_flags |= MS_RDONLY;
- /* determine the minimum size of new large inodes, if present */ - if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) { - sbi->s_want_extra_isize = sizeof(struct ext4_inode) - - EXT4_GOOD_OLD_INODE_SIZE; - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) { - if (sbi->s_want_extra_isize < - le16_to_cpu(es->s_want_extra_isize)) - sbi->s_want_extra_isize = - le16_to_cpu(es->s_want_extra_isize); - if (sbi->s_want_extra_isize < - le16_to_cpu(es->s_min_extra_isize)) - sbi->s_want_extra_isize = - le16_to_cpu(es->s_min_extra_isize); - } - } - /* Check if enough inode space is available */ - if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize > - sbi->s_inode_size) { - sbi->s_want_extra_isize = sizeof(struct ext4_inode) - - EXT4_GOOD_OLD_INODE_SIZE; - ext4_msg(sb, KERN_INFO, "required extra inode space not" - "available"); - } + ext4_clamp_want_extra_isize(sb);
err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb)); if (err) {