I resurect and refreshed this old patch from https://lists.linux-foundation.org/pipermail/containers/2007-February/003726.html This patch makes automount to work within a container. Make autofs4 container-friendly by caching struct pid reference rather than pid_t and using pid_nr() to retreive a task's pid_t. ChangeLog: - Refreshed against linux-next (added dev-ioctl.c) - Fix Eric Biederman's comments - Use find_get_pid() to hold a reference to oz_pgrp and release while unmounting; separate out changes to autofs and autofs4. - Also rollback my earlier change to autofs_wait_queue (pid and tgid in the wait queue are just used to write to a userspace daemon's pipe). - Fix Cedric's comments: retain old prototype of parse_options() and move necessary change to its caller. Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxx> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxx> Cc: Ian Kent <raven@xxxxxxxxxx> Cc: Cedric Le Goater <clg@xxxxxxxxxx> Cc: Dave Hansen <haveblue@xxxxxxxxxx> Cc: Serge E. Hallyn <serge.hallyn@xxxxxxxxxxxxx> Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx> Cc: Helmut Lichtenberg <heli@xxxxxxxxxx> --- fs/autofs4/autofs_i.h | 28 ++++++++++++++-------------- fs/autofs4/dev-ioctl.c | 2 +- fs/autofs4/inode.c | 22 ++++++++++++++++------ fs/autofs4/root.c | 3 ++- fs/autofs4/waitq.c | 4 ++-- 5 files changed, 35 insertions(+), 24 deletions(-) diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 3d283ab..e7298a1 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -39,25 +39,25 @@ /* #define DEBUG */ #ifdef DEBUG -#define DPRINTK(fmt, args...) \ -do { \ - printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \ - current->pid, __func__, ##args); \ +#define DPRINTK(fmt, args...) \ +do { \ + printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \ + pid_nr(task_pid(current)), __func__, ##args); \ } while (0) #else #define DPRINTK(fmt, args...) do {} while (0) #endif -#define AUTOFS_WARN(fmt, args...) \ -do { \ - printk(KERN_WARNING "pid %d: %s: " fmt "\n", \ - current->pid, __func__, ##args); \ +#define AUTOFS_WARN(fmt, args...) \ +do { \ + printk(KERN_WARNING "pid %d: %s: " fmt "\n", \ + pid_nr(task_pid(current)), __func__, ##args); \ } while (0) -#define AUTOFS_ERROR(fmt, args...) \ -do { \ - printk(KERN_ERR "pid %d: %s: " fmt "\n", \ - current->pid, __func__, ##args); \ +#define AUTOFS_ERROR(fmt, args...) \ +do { \ + printk(KERN_ERR "pid %d: %s: " fmt "\n", \ + pid_nr(task_pid(current)), __func__, ##args); \ } while (0) /* Unified info structure. This is pointed to by both the dentry and @@ -122,7 +122,7 @@ struct autofs_sb_info { u32 magic; int pipefd; struct file *pipe; - pid_t oz_pgrp; + struct pid *oz_pgrp; int catatonic; int version; int sub_version; @@ -156,7 +156,7 @@ static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) filesystem without "magic".) */ static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { - return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp; + return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp; } /* Does a dentry have some pending activity? */ diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c index eff9a41..94a523a 100644 --- a/fs/autofs4/dev-ioctl.c +++ b/fs/autofs4/dev-ioctl.c @@ -377,7 +377,7 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp, fput(pipe); goto out; } - sbi->oz_pgrp = task_pgrp_nr(current); + sbi->oz_pgrp = task_pgrp(current); sbi->pipefd = pipefd; sbi->pipe = pipe; sbi->catatonic = 0; diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c index 821b2b9..b36af5a 100644 --- a/fs/autofs4/inode.c +++ b/fs/autofs4/inode.c @@ -111,7 +111,7 @@ void autofs4_kill_sb(struct super_block *sb) /* Free wait queues, close pipe */ autofs4_catatonic_mode(sbi); - + put_pid(sbi->oz_pgrp); sb->s_fs_info = NULL; kfree(sbi); @@ -133,7 +133,7 @@ static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt) seq_printf(m, ",uid=%u", root_inode->i_uid); if (root_inode->i_gid != 0) seq_printf(m, ",gid=%u", root_inode->i_gid); - seq_printf(m, ",pgrp=%d", sbi->oz_pgrp); + seq_printf(m, ",pgrp=%d", pid_nr(sbi->oz_pgrp)); seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); seq_printf(m, ",minproto=%d", sbi->min_proto); seq_printf(m, ",maxproto=%d", sbi->max_proto); @@ -263,6 +263,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent) int pipefd; struct autofs_sb_info *sbi; struct autofs_info *ino; + pid_t pgid; sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); if (!sbi) @@ -275,7 +276,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent) sbi->pipe = NULL; sbi->catatonic = 1; sbi->exp_timeout = 0; - sbi->oz_pgrp = task_pgrp_nr(current); + sbi->oz_pgrp = task_pgrp(current); sbi->sb = s; sbi->version = 0; sbi->sub_version = 0; @@ -314,7 +315,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent) /* Can this call block? */ if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid, - &sbi->oz_pgrp, &sbi->type, &sbi->min_proto, + &pgid, &sbi->type, &sbi->min_proto, &sbi->max_proto)) { printk("autofs: called with bogus options\n"); goto fail_dput; @@ -342,12 +343,19 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent) sbi->version = sbi->max_proto; sbi->sub_version = AUTOFS_PROTO_SUBVERSION; - DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp); + DPRINTK("pipe fd = %d, pgrp = %u", pipefd, pgid); + + sbi->oz_pgrp = find_get_pid(pgid); + if (!sbi->oz_pgrp) { + printk("autofs: could not find process group %d\n", pgid); + goto fail_dput; + } + pipe = fget(pipefd); if (!pipe) { printk("autofs: could not open pipe file descriptor\n"); - goto fail_dput; + goto fail_put_pid; } if (!pipe->f_op || !pipe->f_op->write) goto fail_fput; @@ -368,6 +376,8 @@ fail_fput: printk("autofs: pipe file descriptor does not contain proper ops\n"); fput(pipe); /* fall through */ +fail_put_pid: + put_pid(sbi->oz_pgrp); fail_dput: dput(root); goto fail_free; diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index 9dd29c2..b1d199a 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -539,7 +539,8 @@ static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, s oz_mode = autofs4_oz_mode(sbi); DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d", - current->pid, task_pgrp_nr(current), sbi->catatonic, oz_mode); + pid_nr(task_pid(current)), task_pgrp_nr(current), + sbi->catatonic, oz_mode); active = autofs4_lookup_active(dentry); if (active) { diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 2341375..7b68e4a 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -387,8 +387,8 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry, wq->ino = autofs4_get_ino(sbi); wq->uid = current_uid(); wq->gid = current_gid(); - wq->pid = current->pid; - wq->tgid = current->tgid; + wq->pid = pid_nr(task_pid(current)); + wq->tgid = pid_nr(task_tgid(current)); wq->status = -EINTR; /* Status return if interrupted */ wq->wait_ctr = 2; mutex_unlock(&sbi->wq_mutex); -- 1.7.0.4 _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
