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| author | Sahitya Tummala <stummala@codeaurora.org> | 2018-12-26 11:20:29 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-12 19:47:17 +0100 |
| commit | 69e7f87745e70ca8d9b8a72e045738236d367670 (patch) | |
| tree | 96ce17b8dd58d67fc26297fab123fe6d3261276e | |
| parent | 5d3b4cd8734b41ea04e384d231a09244cfcaebca (diff) | |
| download | linux-rt-69e7f87745e70ca8d9b8a72e045738236d367670.tar.gz | |
f2fs: fix use-after-free issue when accessing sbi->stat_info
[ Upstream commit 60aa4d5536ab7fe32433ca1173bd9d6633851f27 ]
iput() on sbi->node_inode can update sbi->stat_info
in the below context, if the f2fs_write_checkpoint()
has failed with error.
f2fs_balance_fs_bg+0x1ac/0x1ec
f2fs_write_node_pages+0x4c/0x260
do_writepages+0x80/0xbc
__writeback_single_inode+0xdc/0x4ac
writeback_single_inode+0x9c/0x144
write_inode_now+0xc4/0xec
iput+0x194/0x22c
f2fs_put_super+0x11c/0x1e8
generic_shutdown_super+0x70/0xf4
kill_block_super+0x2c/0x5c
kill_f2fs_super+0x44/0x50
deactivate_locked_super+0x60/0x8c
deactivate_super+0x68/0x74
cleanup_mnt+0x40/0x78
Fix this by moving f2fs_destroy_stats() further below iput() in
both f2fs_put_super() and f2fs_fill_super() paths.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/f2fs/super.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 338138b34993..c9639ef0e8d5 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1039,9 +1039,6 @@ static void f2fs_put_super(struct super_block *sb) f2fs_write_checkpoint(sbi, &cpc); } - /* f2fs_write_checkpoint can update stat informaion */ - f2fs_destroy_stats(sbi); - /* * normally superblock is clean, so we need to release this. * In addition, EIO will skip do checkpoint, we need this as well. @@ -1061,6 +1058,12 @@ static void f2fs_put_super(struct super_block *sb) iput(sbi->node_inode); iput(sbi->meta_inode); + /* + * iput() can update stat information, if f2fs_write_checkpoint() + * above failed with error. + */ + f2fs_destroy_stats(sbi); + /* destroy f2fs internal modules */ f2fs_destroy_node_manager(sbi); f2fs_destroy_segment_manager(sbi); @@ -2980,30 +2983,30 @@ try_onemore: f2fs_build_gc_manager(sbi); + err = f2fs_build_stats(sbi); + if (err) + goto free_nm; + /* get an inode for node space */ sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi)); if (IS_ERR(sbi->node_inode)) { f2fs_msg(sb, KERN_ERR, "Failed to read node inode"); err = PTR_ERR(sbi->node_inode); - goto free_nm; + goto free_stats; } - err = f2fs_build_stats(sbi); - if (err) - goto free_node_inode; - /* read root inode and dentry */ root = f2fs_iget(sb, F2FS_ROOT_INO(sbi)); if (IS_ERR(root)) { f2fs_msg(sb, KERN_ERR, "Failed to read root inode"); err = PTR_ERR(root); - goto free_stats; + goto free_node_inode; } if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size || !root->i_nlink) { iput(root); err = -EINVAL; - goto free_stats; + goto free_node_inode; } sb->s_root = d_make_root(root); /* allocate root dentry */ @@ -3121,12 +3124,12 @@ free_sysfs: free_root_inode: dput(sb->s_root); sb->s_root = NULL; -free_stats: - f2fs_destroy_stats(sbi); free_node_inode: f2fs_release_ino_entry(sbi, true); truncate_inode_pages_final(NODE_MAPPING(sbi)); iput(sbi->node_inode); +free_stats: + f2fs_destroy_stats(sbi); free_nm: f2fs_destroy_node_manager(sbi); free_sm: |