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.
Assigned-off-by: Vitaliy Gusev <vgusev@xxxxxxxxxx>
Acked-by: Serge Hallyn <serue@xxxxxxxxxx>
fs/locks.c | 26 +++++++++++++++++++++-----
include/linux/fs.h | 3 ++-
2 files changed, 23 insertions(+), 6 deletions(-)
diff --git a/fs/locks.c b/fs/locks.c
index 8b8388e..14989fa 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 +588,9 @@ 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);
+ put_pid(fl->fl_nspid);
+ fl->fl_nspid = NULL;
+
locks_wake_up_blocks(fl);
locks_free_lock(fl);
}
@@ -673,9 +680,12 @@ 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;
@@ -2084,6 +2094,12 @@ 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;
@@ -2124,16 +2140,16 @@ 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 b3ec4a4..1fb952f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -869,7 +869,8 @@ struct file_lock {
struct list_head fl_link; /* doubly linked list of all locks */
struct list_head fl_block; /* circular list of blocked processes */
fl_owner_t fl_owner;
- unsigned int fl_pid;
+ unsigned int fl_pid; /* unique id and sometimes global pid */
+ struct pid *fl_nspid; /* to calculate owner pid_nr for userspace */
wait_queue_head_t fl_wait;
struct file *fl_file;
unsigned char fl_flags;
diff --git a/fs/locks.c b/fs/locks.c
index 8b8388e..d2d3d75 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);
}
@@ -673,14 +682,16 @@ 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);
/* This function tests for deadlock condition before putting a process to
@@ -2084,6 +2095,12 @@ 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;
@@ -2124,16 +2141,16 @@ 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 b3ec4a4..5876f68 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -870,6 +870,7 @@ 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;
