From 74dbbdd7fdc11763f4698d2f3e684cf4446951e6 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 6 May 2009 01:07:50 -0400 Subject: New helper: deactivate_locked_super() Does equivalent of up_write(&s->s_umount); deactivate_super(s); However, it does not does not unlock it until it's all over. As the result, it's safe to use to dispose of new superblock on ->get_sb() failure exits - nobody will see the sucker until it's all over. Equivalent using up_write/deactivate_super is safe for that purpose if superblock is either safe to use or has NULL ->s_root when we unlock. Normally filesystems take the required precautions, but a) we do have bugs in that area in some of them. b) up_write/deactivate_super sequence is extremely common, so the helper makes sense anyway. Signed-off-by: Al Viro --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/fs.h') diff --git a/include/linux/fs.h b/include/linux/fs.h index 5bed436..11484d0 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1775,6 +1775,7 @@ void kill_block_super(struct super_block *sb); void kill_anon_super(struct super_block *sb); void kill_litter_super(struct super_block *sb); void deactivate_super(struct super_block *sb); +void deactivate_locked_super(struct super_block *sb); int set_anon_super(struct super_block *s, void *data); struct super_block *sget(struct file_system_type *type, int (*test)(struct super_block *,void *), -- cgit v1.1 From 6e8341a11eb21826b7192d0bb88cb5b44900a9af Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 6 Apr 2009 11:16:22 -0400 Subject: Switch open_exec() and sys_uselib() to do_open_filp() ... and make path_lookup_open() static Signed-off-by: Al Viro --- include/linux/fs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/fs.h') diff --git a/include/linux/fs.h b/include/linux/fs.h index 11484d0..ed78842 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2118,7 +2118,7 @@ extern struct file *create_write_pipe(int flags); extern void free_write_pipe(struct file *); extern struct file *do_filp_open(int dfd, const char *pathname, - int open_flag, int mode); + int open_flag, int mode, int acc_mode); extern int may_open(struct path *, int, int); extern int kernel_read(struct file *, unsigned long, char *, unsigned long); -- cgit v1.1 From 2a32cebd6cbcc43996c3e2d114fa32ba1e71192a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 8 May 2009 16:05:57 -0400 Subject: Fix races around the access to ->s_options Put generic_show_options read access to s_options under rcu_read_lock, split save_mount_options() into "we are setting it the first time" (uses in foo_fill_super()) and "we are relacing and freeing the old one", synchronize_rcu() before kfree() in the latter. Signed-off-by: Al Viro --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/fs.h') diff --git a/include/linux/fs.h b/include/linux/fs.h index ed78842..3b534e5 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2368,6 +2368,7 @@ extern void file_update_time(struct file *file); extern int generic_show_options(struct seq_file *m, struct vfsmount *mnt); extern void save_mount_options(struct super_block *sb, char *options); +extern void replace_mount_options(struct super_block *sb, char *options); static inline ino_t parent_ino(struct dentry *dentry) { -- cgit v1.1