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author | Theodore Ts'o <tytso@mit.edu> | 2013-03-11 23:39:59 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-05 10:16:52 -0700 |
commit | 503f4bdcc078e7abee273a85ce322de81b18a224 (patch) | |
tree | 30eb5483102eb88ac8e5d9c9ddb84e6437ddd6ba | |
parent | 7fb54baf47818c2a76999ff907e2cecf25b98218 (diff) | |
download | lwn-503f4bdcc078e7abee273a85ce322de81b18a224.tar.gz lwn-503f4bdcc078e7abee273a85ce322de81b18a224.zip |
ext4: use atomic64_t for the per-flexbg free_clusters count
commit 90ba983f6889e65a3b506b30dc606aa9d1d46cd2 upstream.
A user who was using a 8TB+ file system and with a very large flexbg
size (> 65536) could cause the atomic_t used in the struct flex_groups
to overflow. This was detected by PaX security patchset:
http://forums.grsecurity.net/viewtopic.php?f=3&t=3289&p=12551#p12551
This bug was introduced in commit 9f24e4208f7e, so it's been around
since 2.6.30. :-(
Fix this by using an atomic64_t for struct orlav_stats's
free_clusters.
[Backported for 3.0-stable. Renamed free_clusters back to free_blocks;
fixed a few more atomic_read's of free_blocks left in 3.0.]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Lingzhu Xiang <lxiang@redhat.com>
Reviewed-by: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | fs/ext4/ext4.h | 6 | ||||
-rw-r--r-- | fs/ext4/ialloc.c | 18 | ||||
-rw-r--r-- | fs/ext4/mballoc.c | 10 | ||||
-rw-r--r-- | fs/ext4/resize.c | 4 | ||||
-rw-r--r-- | fs/ext4/super.c | 4 |
5 files changed, 21 insertions, 21 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index e0113aa0d3a2..2041de7a7004 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -288,9 +288,9 @@ struct ext4_group_desc */ struct flex_groups { - atomic_t free_inodes; - atomic_t free_blocks; - atomic_t used_dirs; + atomic64_t free_blocks; + atomic_t free_inodes; + atomic_t used_dirs; }; #define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */ diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 29272de30232..dd732c7aa814 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -345,8 +345,8 @@ static int find_group_flex(struct super_block *sb, struct inode *parent, ext4_group_t ngroups = ext4_get_groups_count(sb); int flex_size = ext4_flex_bg_size(sbi); ext4_group_t best_flex = parent_fbg_group; - int blocks_per_flex = sbi->s_blocks_per_group * flex_size; - int flexbg_free_blocks; + ext4_fsblk_t blocks_per_flex = sbi->s_blocks_per_group * flex_size; + ext4_fsblk_t flexbg_free_blocks; int flex_freeb_ratio; ext4_group_t n_fbg_groups; ext4_group_t i; @@ -355,7 +355,7 @@ static int find_group_flex(struct super_block *sb, struct inode *parent, sbi->s_log_groups_per_flex; find_close_to_parent: - flexbg_free_blocks = atomic_read(&flex_group[best_flex].free_blocks); + flexbg_free_blocks = atomic64_read(&flex_group[best_flex].free_blocks); flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex; if (atomic_read(&flex_group[best_flex].free_inodes) && flex_freeb_ratio > free_block_ratio) @@ -370,7 +370,7 @@ find_close_to_parent: if (i == parent_fbg_group || i == parent_fbg_group - 1) continue; - flexbg_free_blocks = atomic_read(&flex_group[i].free_blocks); + flexbg_free_blocks = atomic64_read(&flex_group[i].free_blocks); flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex; if (flex_freeb_ratio > free_block_ratio && @@ -380,14 +380,14 @@ find_close_to_parent: } if ((atomic_read(&flex_group[best_flex].free_inodes) == 0) || - ((atomic_read(&flex_group[i].free_blocks) > - atomic_read(&flex_group[best_flex].free_blocks)) && + ((atomic64_read(&flex_group[i].free_blocks) > + atomic64_read(&flex_group[best_flex].free_blocks)) && atomic_read(&flex_group[i].free_inodes))) best_flex = i; } if (!atomic_read(&flex_group[best_flex].free_inodes) || - !atomic_read(&flex_group[best_flex].free_blocks)) + !atomic64_read(&flex_group[best_flex].free_blocks)) return -1; found_flexbg: @@ -406,8 +406,8 @@ out: } struct orlov_stats { + __u64 free_blocks; __u32 free_inodes; - __u32 free_blocks; __u32 used_dirs; }; @@ -424,7 +424,7 @@ static void get_orlov_stats(struct super_block *sb, ext4_group_t g, if (flex_size > 1) { stats->free_inodes = atomic_read(&flex_group[g].free_inodes); - stats->free_blocks = atomic_read(&flex_group[g].free_blocks); + stats->free_blocks = atomic64_read(&flex_group[g].free_blocks); stats->used_dirs = atomic_read(&flex_group[g].used_dirs); return; } diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 31bbdb52b899..35959f641986 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2814,8 +2814,8 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, if (sbi->s_log_groups_per_flex) { ext4_group_t flex_group = ext4_flex_group(sbi, ac->ac_b_ex.fe_group); - atomic_sub(ac->ac_b_ex.fe_len, - &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_sub(ac->ac_b_ex.fe_len, + &sbi->s_flex_groups[flex_group].free_blocks); } err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh); @@ -4614,7 +4614,7 @@ do_more: if (sbi->s_log_groups_per_flex) { ext4_group_t flex_group = ext4_flex_group(sbi, block_group); - atomic_add(count, &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_add(count, &sbi->s_flex_groups[flex_group].free_blocks); } ext4_mb_unload_buddy(&e4b); @@ -4745,8 +4745,8 @@ void ext4_add_groupblocks(handle_t *handle, struct super_block *sb, if (sbi->s_log_groups_per_flex) { ext4_group_t flex_group = ext4_flex_group(sbi, block_group); - atomic_add(blocks_freed, - &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_add(blocks_freed, + &sbi->s_flex_groups[flex_group].free_blocks); } ext4_mb_unload_buddy(&e4b); diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 244100f08fcb..d2661aaca32a 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -929,8 +929,8 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) sbi->s_log_groups_per_flex) { ext4_group_t flex_group; flex_group = ext4_flex_group(sbi, input->group); - atomic_add(input->free_blocks_count, - &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_add(input->free_blocks_count, + &sbi->s_flex_groups[flex_group].free_blocks); atomic_add(EXT4_INODES_PER_GROUP(sb), &sbi->s_flex_groups[flex_group].free_inodes); } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index c6a3363f956e..e05cd34ccffd 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1992,8 +1992,8 @@ static int ext4_fill_flex_info(struct super_block *sb) flex_group = ext4_flex_group(sbi, i); atomic_add(ext4_free_inodes_count(sb, gdp), &sbi->s_flex_groups[flex_group].free_inodes); - atomic_add(ext4_free_blks_count(sb, gdp), - &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_add(ext4_free_blks_count(sb, gdp), + &sbi->s_flex_groups[flex_group].free_blocks); atomic_add(ext4_used_dirs_count(sb, gdp), &sbi->s_flex_groups[flex_group].used_dirs); } |