Since commit c69899a17ca4 "NFSv4: Update of VFS byte range lock must be
atomic with the stateid update", NFSv4 has been inserting locks in rpciod
worker context. The result is that the file_lock's fl_nspid is the
kworker's pid instead of the original userspace pid. We can fix that up by
setting fl_nspid in locks_allocate_lock, and tranfer it to the file_lock
that's eventually recorded.
Also, let's set fl_nspid directly in a few places it is stored on the
stack. The use of fl_pid is retained for lock managers that do not set
fl_nspid and instead wish to use and record private fl_pid numbers.
Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
---
fs/locks.c | 44 ++++++++++++++++++++++++++------------------
1 file changed, 26 insertions(+), 18 deletions(-)
diff --git a/fs/locks.c b/fs/locks.c
index af2031a1fcff..959b3f93f4bd 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -249,7 +249,7 @@ locks_dump_ctx_list(struct list_head *list, char *list_type)
struct file_lock *fl;
list_for_each_entry(fl, list, fl_list) {
- pr_warn("%s: fl_owner=%p fl_flags=0x%x fl_type=0x%x fl_pid=%u\n", list_type, fl->fl_owner, fl->fl_flags, fl->fl_type, fl->fl_pid);
+ pr_warn("%s: fl_owner=%p fl_flags=0x%x fl_type=0x%x fl_pid=%u\n", list_type, fl->fl_owner, fl->fl_flags, fl->fl_type, pid_vnr(fl->fl_nspid));
}
}
@@ -294,8 +294,10 @@ struct file_lock *locks_alloc_lock(void)
{
struct file_lock *fl = kmem_cache_zalloc(filelock_cache, GFP_KERNEL);
- if (fl)
+ if (fl) {
locks_init_lock_heads(fl);
+ fl->fl_nspid = get_pid(task_tgid(current));
+ }
return fl;
}
@@ -328,6 +330,8 @@ void locks_free_lock(struct file_lock *fl)
BUG_ON(!hlist_unhashed(&fl->fl_link));
locks_release_private(fl);
+ if (fl->fl_nspid)
+ put_pid(fl->fl_nspid);
kmem_cache_free(filelock_cache, fl);
}
EXPORT_SYMBOL(locks_free_lock);
@@ -357,8 +361,15 @@ EXPORT_SYMBOL(locks_init_lock);
*/
void locks_copy_conflock(struct file_lock *new, struct file_lock *fl)
{
+ struct pid *replace_pid = new->fl_nspid;
+
new->fl_owner = fl->fl_owner;
new->fl_pid = fl->fl_pid;
+ if (fl->fl_nspid) {
+ new->fl_nspid = get_pid(fl->fl_nspid);
+ if (replace_pid)
+ put_pid(replace_pid);
+ }
new->fl_file = NULL;
new->fl_flags = fl->fl_flags;
new->fl_type = fl->fl_type;
@@ -422,7 +433,6 @@ flock_make_lock(struct file *filp, unsigned int cmd)
fl->fl_file = filp;
fl->fl_owner = filp;
- fl->fl_pid = current->tgid;
fl->fl_flags = FL_FLOCK;
fl->fl_type = type;
fl->fl_end = OFFSET_MAX;
@@ -482,7 +492,6 @@ static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
fl->fl_end = OFFSET_MAX;
fl->fl_owner = current->files;
- fl->fl_pid = current->tgid;
fl->fl_file = filp;
fl->fl_flags = FL_POSIX;
fl->fl_ops = NULL;
@@ -547,8 +556,6 @@ static int lease_init(struct file *filp, long type, struct file_lock *fl)
return -EINVAL;
fl->fl_owner = filp;
- fl->fl_pid = current->tgid;
-
fl->fl_file = filp;
fl->fl_flags = FL_LEASE;
fl->fl_start = 0;
@@ -733,7 +740,6 @@ static void locks_wake_up_blocks(struct file_lock *blocker)
static void
locks_insert_lock_ctx(struct file_lock *fl, struct list_head *before)
{
- fl->fl_nspid = get_pid(task_tgid(current));
list_add_tail(&fl->fl_list, before);
locks_insert_global_locks(fl);
}
@@ -743,10 +749,6 @@ locks_unlink_lock_ctx(struct file_lock *fl)
{
locks_delete_global_locks(fl);
list_del_init(&fl->fl_list);
- if (fl->fl_nspid) {
- put_pid(fl->fl_nspid);
- fl->fl_nspid = NULL;
- }
locks_wake_up_blocks(fl);
}
@@ -823,8 +825,6 @@ posix_test_lock(struct file *filp, struct file_lock *fl)
list_for_each_entry(cfl, &ctx->flc_posix, fl_list) {
if (posix_locks_conflict(fl, cfl)) {
locks_copy_conflock(fl, cfl);
- if (cfl->fl_nspid)
- fl->fl_pid = pid_vnr(cfl->fl_nspid);
goto out;
}
}
@@ -1298,7 +1298,7 @@ int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start,
bool sleep = false;
locks_init_lock(&fl);
- fl.fl_pid = current->tgid;
+ fl.fl_nspid = get_pid(task_tgid(current));
fl.fl_file = filp;
fl.fl_flags = FL_POSIX | FL_ACCESS;
if (filp && !(filp->f_flags & O_NONBLOCK))
@@ -1336,6 +1336,7 @@ int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start,
break;
}
+ put_pid(fl.fl_nspid);
return error;
}
@@ -2052,7 +2053,7 @@ EXPORT_SYMBOL_GPL(vfs_test_lock);
static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
{
- flock->l_pid = IS_OFDLCK(fl) ? -1 : fl->fl_pid;
+ flock->l_pid = IS_OFDLCK(fl) ? -1 : pid_vnr(fl->fl_nspid);
#if BITS_PER_LONG == 32
/*
* Make sure we can represent the posix lock via
@@ -2074,7 +2075,7 @@ static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
#if BITS_PER_LONG == 32
static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
{
- flock->l_pid = IS_OFDLCK(fl) ? -1 : fl->fl_pid;
+ flock->l_pid = IS_OFDLCK(fl) ? -1 : pid_vnr(fl->fl_nspid);
flock->l_start = fl->fl_start;
flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
fl->fl_end - fl->fl_start + 1;
@@ -2093,6 +2094,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
int error;
error = -EFAULT;
+ file_lock.fl_nspid = get_pid(task_tgid(current));
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
error = -EINVAL;
@@ -2129,6 +2131,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
rel_priv:
locks_release_private(&file_lock);
out:
+ put_pid(file_lock.fl_nspid);
return error;
}
@@ -2322,6 +2325,7 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
int error;
error = -EFAULT;
+ file_lock.fl_nspid = get_pid(task_tgid(current));
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
error = -EINVAL;
@@ -2356,6 +2360,7 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
locks_release_private(&file_lock);
out:
+ put_pid(file_lock.fl_nspid);
return error;
}
@@ -2482,7 +2487,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
lock.fl_start = 0;
lock.fl_end = OFFSET_MAX;
lock.fl_owner = owner;
- lock.fl_pid = current->tgid;
+ lock.fl_nspid = get_pid(task_tgid(current));
lock.fl_file = filp;
lock.fl_ops = NULL;
lock.fl_lmops = NULL;
@@ -2491,6 +2496,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
if (lock.fl_ops && lock.fl_ops->fl_release_private)
lock.fl_ops->fl_release_private(&lock);
+ put_pid(lock.fl_nspid);
trace_locks_remove_posix(inode, &lock, error);
}
@@ -2502,7 +2508,6 @@ locks_remove_flock(struct file *filp, struct file_lock_context *flctx)
{
struct file_lock fl = {
.fl_owner = filp,
- .fl_pid = current->tgid,
.fl_file = filp,
.fl_flags = FL_FLOCK | FL_CLOSE,
.fl_type = F_UNLCK,
@@ -2513,6 +2518,8 @@ locks_remove_flock(struct file *filp, struct file_lock_context *flctx)
if (list_empty(&flctx->flc_flock))
return;
+ fl.fl_nspid = get_pid(task_tgid(current));
+
if (filp->f_op->flock && is_remote_lock(filp))
filp->f_op->flock(filp, F_SETLKW, &fl);
else
@@ -2520,6 +2527,7 @@ locks_remove_flock(struct file *filp, struct file_lock_context *flctx)
if (fl.fl_ops && fl.fl_ops->fl_release_private)
fl.fl_ops->fl_release_private(&fl);
+ put_pid(fl.fl_nspid);
}
/* The i_flctx must be valid when calling into here */
--
2.9.3
