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| author | Vitaliy Gusev <vgusev@openvz.org> | 2008-01-17 00:07:08 +0000 |
|---|---|---|
| committer | J. Bruce Fields <bfields@citi.umich.edu> | 2008-02-03 17:51:36 -0500 |
| commit | ab1f16116527e42dec8aee176d673a41a881b809 (patch) | |
| tree | 0d20fa10151e43f9f104986a2b89ec88ca0135af | |
| parent | 4321e01e7dce8042758349ffa2929c723b0d4107 (diff) | |
| download | blackbird-op-linux-ab1f16116527e42dec8aee176d673a41a881b809.tar.gz blackbird-op-linux-ab1f16116527e42dec8aee176d673a41a881b809.zip | |
pid-namespaces-vs-locks-interaction
fcntl(F_GETLK,..) can return pid of process for not current pid namespace
(if process is belonged to the several namespaces). It is true also for
pids in /proc/locks. So correct behavior is saving pointer to the struct
pid of the process lock owner.
Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
| -rw-r--r-- | fs/locks.c | 29 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 |
2 files changed, 24 insertions, 6 deletions
diff --git a/fs/locks.c b/fs/locks.c index faddccb6336a..49354b9c7dc1 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -125,6 +125,7 @@ #include <linux/syscalls.h> #include <linux/time.h> #include <linux/rcupdate.h> +#include <linux/pid_namespace.h> #include <asm/semaphore.h> #include <asm/uaccess.h> @@ -185,6 +186,7 @@ void locks_init_lock(struct file_lock *fl) fl->fl_fasync = NULL; fl->fl_owner = NULL; fl->fl_pid = 0; + fl->fl_nspid = NULL; fl->fl_file = NULL; fl->fl_flags = 0; fl->fl_type = 0; @@ -553,6 +555,8 @@ static void locks_insert_lock(struct file_lock **pos, struct file_lock *fl) { list_add(&fl->fl_link, &file_lock_list); + fl->fl_nspid = get_pid(task_tgid(current)); + /* insert into file's list */ fl->fl_next = *pos; *pos = fl; @@ -584,6 +588,11 @@ static void locks_delete_lock(struct file_lock **thisfl_p) if (fl->fl_ops && fl->fl_ops->fl_remove) fl->fl_ops->fl_remove(fl); + if (fl->fl_nspid) { + put_pid(fl->fl_nspid); + fl->fl_nspid = NULL; + } + locks_wake_up_blocks(fl); locks_free_lock(fl); } @@ -646,14 +655,16 @@ posix_test_lock(struct file *filp, struct file_lock *fl) if (posix_locks_conflict(fl, cfl)) break; } - if (cfl) + if (cfl) { __locks_copy_lock(fl, cfl); - else + if (cfl->fl_nspid) + fl->fl_pid = pid_nr_ns(cfl->fl_nspid, + task_active_pid_ns(current)); + } else fl->fl_type = F_UNLCK; unlock_kernel(); return; } - EXPORT_SYMBOL(posix_test_lock); /* @@ -2070,6 +2081,12 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, int id, char *pfx) { struct inode *inode = NULL; + unsigned int fl_pid; + + if (fl->fl_nspid) + fl_pid = pid_nr_ns(fl->fl_nspid, task_active_pid_ns(current)); + else + fl_pid = fl->fl_pid; if (fl->fl_file != NULL) inode = fl->fl_file->f_path.dentry->d_inode; @@ -2110,16 +2127,16 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, } if (inode) { #ifdef WE_CAN_BREAK_LSLK_NOW - seq_printf(f, "%d %s:%ld ", fl->fl_pid, + seq_printf(f, "%d %s:%ld ", fl_pid, inode->i_sb->s_id, inode->i_ino); #else /* userspace relies on this representation of dev_t ;-( */ - seq_printf(f, "%d %02x:%02x:%ld ", fl->fl_pid, + seq_printf(f, "%d %02x:%02x:%ld ", fl_pid, MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev), inode->i_ino); #endif } else { - seq_printf(f, "%d <none>:0 ", fl->fl_pid); + seq_printf(f, "%d <none>:0 ", fl_pid); } if (IS_POSIX(fl)) { if (fl->fl_end == OFFSET_MAX) diff --git a/include/linux/fs.h b/include/linux/fs.h index a516b6716870..b7736ab8bb5e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -872,6 +872,7 @@ struct file_lock { struct list_head fl_block; /* circular list of blocked processes */ fl_owner_t fl_owner; unsigned int fl_pid; + struct pid *fl_nspid; wait_queue_head_t fl_wait; struct file *fl_file; unsigned char fl_flags; |
