Message ID | 20190129150858.10430-1-stefan.bader@canonical.com |
---|---|
State | New |
Headers | show |
Series | [REGRESSION/bionic] ext4: fix false negatives *and* false positives in ext4_check_descriptors() | expand |
On 29/01/2019 15:08, Stefan Bader wrote: > From: Theodore Ts'o <tytso@mit.edu> > > BugLink: https://bugs.launchpad.net/bugs/1813727 > > Ext4_check_descriptors() was getting called before s_gdb_count was > initialized. So for file systems w/o the meta_bg feature, allocation > bitmaps could overlap the block group descriptors and ext4 wouldn't > notice. > > For file systems with the meta_bg feature enabled, there was a > fencepost error which would cause the ext4_check_descriptors() to > incorrectly believe that the block allocation bitmap overlaps with the > block group descriptor blocks, and it would reject the mount. > > Fix both of these problems. > > Signed-off-by: Theodore Ts'o <tytso@mit.edu> > Cc: stable@vger.kernel.org > > (cherry picked from commit 44de022c4382541cebdd6de4465d1f4f465ff1dd) > Signed-off-by: Stefan Bader <stefan.bader@canonical.com> > --- > > This likely was introduced via upstream stable 2018-12-12 > e1d8355dd9508466024730813a84c8ee386d7b65. > > fs/ext4/super.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 6503bbac60cb..4288dede4c69 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -2328,7 +2328,7 @@ static int ext4_check_descriptors(struct super_block *sb, > struct ext4_sb_info *sbi = EXT4_SB(sb); > ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); > ext4_fsblk_t last_block; > - ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1; > + ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0); > ext4_fsblk_t block_bitmap; > ext4_fsblk_t inode_bitmap; > ext4_fsblk_t inode_table; > @@ -4083,14 +4083,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > goto failed_mount2; > } > } > + sbi->s_gdb_count = db_count; > if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) { > ext4_msg(sb, KERN_ERR, "group descriptors corrupted!"); > ret = -EFSCORRUPTED; > goto failed_mount2; > } > > - sbi->s_gdb_count = db_count; > - > timer_setup(&sbi->s_err_report, print_daily_error_info, 0); > > /* Register extent status tree shrinker */ > Clean cherry pick, addresses the issue fine. Acked-by: Colin Ian King <colin.king@canonical.com>
Clean cherry-pick.
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
On 2019-01-29 16:08:58, Stefan Bader wrote: > From: Theodore Ts'o <tytso@mit.edu> > > BugLink: https://bugs.launchpad.net/bugs/1813727 > > Ext4_check_descriptors() was getting called before s_gdb_count was > initialized. So for file systems w/o the meta_bg feature, allocation > bitmaps could overlap the block group descriptors and ext4 wouldn't > notice. > > For file systems with the meta_bg feature enabled, there was a > fencepost error which would cause the ext4_check_descriptors() to > incorrectly believe that the block allocation bitmap overlaps with the > block group descriptor blocks, and it would reject the mount. > > Fix both of these problems. > > Signed-off-by: Theodore Ts'o <tytso@mit.edu> > Cc: stable@vger.kernel.org > > (cherry picked from commit 44de022c4382541cebdd6de4465d1f4f465ff1dd) > Signed-off-by: Stefan Bader <stefan.bader@canonical.com> > --- Acked-by: Tyler Hicks <tyhicks@canonical.com> Tyler
On 29.01.19 16:08, Stefan Bader wrote: > From: Theodore Ts'o <tytso@mit.edu> > > BugLink: https://bugs.launchpad.net/bugs/1813727 > > Ext4_check_descriptors() was getting called before s_gdb_count was > initialized. So for file systems w/o the meta_bg feature, allocation > bitmaps could overlap the block group descriptors and ext4 wouldn't > notice. > > For file systems with the meta_bg feature enabled, there was a > fencepost error which would cause the ext4_check_descriptors() to > incorrectly believe that the block allocation bitmap overlaps with the > block group descriptor blocks, and it would reject the mount. > > Fix both of these problems. > > Signed-off-by: Theodore Ts'o <tytso@mit.edu> > Cc: stable@vger.kernel.org > > (cherry picked from commit 44de022c4382541cebdd6de4465d1f4f465ff1dd) > Signed-off-by: Stefan Bader <stefan.bader@canonical.com> > --- > > This likely was introduced via upstream stable 2018-12-12 > e1d8355dd9508466024730813a84c8ee386d7b65. > > fs/ext4/super.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 6503bbac60cb..4288dede4c69 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -2328,7 +2328,7 @@ static int ext4_check_descriptors(struct super_block *sb, > struct ext4_sb_info *sbi = EXT4_SB(sb); > ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); > ext4_fsblk_t last_block; > - ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1; > + ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0); > ext4_fsblk_t block_bitmap; > ext4_fsblk_t inode_bitmap; > ext4_fsblk_t inode_table; > @@ -4083,14 +4083,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > goto failed_mount2; > } > } > + sbi->s_gdb_count = db_count; > if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) { > ext4_msg(sb, KERN_ERR, "group descriptors corrupted!"); > ret = -EFSCORRUPTED; > goto failed_mount2; > } > > - sbi->s_gdb_count = db_count; > - > timer_setup(&sbi->s_err_report, print_daily_error_info, 0); > > /* Register extent status tree shrinker */ > Totally forgot to reply, this by now is committed and even built and might go out to updates soon. Applied to bionic/master-next. Thanks. -Stefan
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 6503bbac60cb..4288dede4c69 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2328,7 +2328,7 @@ static int ext4_check_descriptors(struct super_block *sb, struct ext4_sb_info *sbi = EXT4_SB(sb); ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); ext4_fsblk_t last_block; - ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1; + ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0); ext4_fsblk_t block_bitmap; ext4_fsblk_t inode_bitmap; ext4_fsblk_t inode_table; @@ -4083,14 +4083,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount2; } } + sbi->s_gdb_count = db_count; if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) { ext4_msg(sb, KERN_ERR, "group descriptors corrupted!"); ret = -EFSCORRUPTED; goto failed_mount2; } - sbi->s_gdb_count = db_count; - timer_setup(&sbi->s_err_report, print_daily_error_info, 0); /* Register extent status tree shrinker */