renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-16 09:13:55 +08:00
Code

ext2: Call dquot_writeback_dquots() with s_umount held

Browse Source 
ext2_sync_fs() could be called without s_umount semaphore held when
called through ext2_write_super() from __ext2_write_inode(). This
function then calls dquot_writeback_dquots() which relies on s_umount to
be held for protection against other quota operations.

In fact __ext2_write_inode() does not need all the functionality
ext2_write_super() provides. It is enough to just write the superblock.
So use ext2_sync_super() instead.

Fixes: 9d1ccbe70e
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2017-04-05 13:32:52 +02:00
parent ab4949640d
commit 6554766150
3 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
fs/ext2/ext2.h
View File

@ -796,7 +796,8 @@ void ext2_error(struct super_block *, const char *, const char *, ...);
extern __printf(3, 4)
void ext2_msg(struct super_block *, const char *, const char *, ...);
extern void ext2_update_dynamic_rev (struct super_block *sb);
extern void ext2_write_super (struct super_block *);
extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
int wait);
/*
* Inodes and files operations

2
fs/ext2/inode.c
View File

@ -1615,7 +1615,7 @@ static int __ext2_write_inode(struct inode *inode, int do_sync)
EXT2_SET_RO_COMPAT_FEATURE(sb,
EXT2_FEATURE_RO_COMPAT_LARGE_FILE);
spin_unlock(&EXT2_SB(sb)->s_lock);
ext2_write_super(sb);
ext2_sync_super(sb, EXT2_SB(sb)->s_es, 1);
}
}
}

9
fs/ext2/super.c
View File

@ -36,8 +36,7 @@
#include "xattr.h"
#include "acl.h"
static void ext2_sync_super(struct super_block *sb,
struct ext2_super_block *es, int wait);
static void ext2_write_super(struct super_block *sb);
static int ext2_remount (struct super_block * sb, int * flags, char * data);
static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
static int ext2_sync_fs(struct super_block *sb, int wait);
@ -1194,8 +1193,8 @@ static void ext2_clear_super_error(struct super_block *sb)
}
}
static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
int wait)
void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
int wait)
{
ext2_clear_super_error(sb);
spin_lock(&EXT2_SB(sb)->s_lock);
@ -1270,7 +1269,7 @@ static int ext2_unfreeze(struct super_block *sb)
return 0;
}
void ext2_write_super(struct super_block *sb)
static void ext2_write_super(struct super_block *sb)
{
if (!(sb->s_flags & MS_RDONLY))
ext2_sync_fs(sb, 1);