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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 15:45:30 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 15:45:30 (GMT)
commita2e5ad45a9741068f357de4dbff50bb37c233e1b (patch)
tree4bf22a8a01301d5c8d10cb3dcf2397e403c37987
parent26c5eaa1326e9703effd01e7cc3cc0d4ad4b3c19 (diff)
parent0b6e9ea041e6c932f5b3a86fae2d60cbcfad4dd2 (diff)
downloadlinux-a2e5ad45a9741068f357de4dbff50bb37c233e1b.tar.gz
linux-a2e5ad45a9741068f357de4dbff50bb37c233e1b.tar.xz
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi: "Support for pid namespaces from Seth and refcount_t work from Elena" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: Add support for pid namespaces fuse: convert fuse_conn.count from atomic_t to refcount_t fuse: convert fuse_req.count from atomic_t to refcount_t fuse: convert fuse_file.count from atomic_t to refcount_t
-rw-r--r--fs/fuse/dev.c24
-rw-r--r--fs/fuse/file.c30
-rw-r--r--fs/fuse/fuse_i.h11
-rw-r--r--fs/fuse/inode.c9
4 files changed, 50 insertions, 24 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c2d7f3a..c16d00e 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -20,6 +20,7 @@
#include <linux/pipe_fs_i.h>
#include <linux/swap.h>
#include <linux/splice.h>
+#include <linux/sched.h>
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
@@ -45,7 +46,7 @@ static void fuse_request_init(struct fuse_req *req, struct page **pages,
INIT_LIST_HEAD(&req->list);
INIT_LIST_HEAD(&req->intr_entry);
init_waitqueue_head(&req->waitq);
- atomic_set(&req->count, 1);
+ refcount_set(&req->count, 1);
req->pages = pages;
req->page_descs = page_descs;
req->max_pages = npages;
@@ -102,21 +103,20 @@ void fuse_request_free(struct fuse_req *req)
void __fuse_get_request(struct fuse_req *req)
{
- atomic_inc(&req->count);
+ refcount_inc(&req->count);
}
/* Must be called with > 1 refcount */
static void __fuse_put_request(struct fuse_req *req)
{
- BUG_ON(atomic_read(&req->count) < 2);
- atomic_dec(&req->count);
+ refcount_dec(&req->count);
}
-static void fuse_req_init_context(struct fuse_req *req)
+static void fuse_req_init_context(struct fuse_conn *fc, struct fuse_req *req)
{
req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
- req->in.h.pid = current->pid;
+ req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
}
void fuse_set_initialized(struct fuse_conn *fc)
@@ -163,7 +163,7 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
goto out;
}
- fuse_req_init_context(req);
+ fuse_req_init_context(fc, req);
__set_bit(FR_WAITING, &req->flags);
if (for_background)
__set_bit(FR_BACKGROUND, &req->flags);
@@ -256,7 +256,7 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
if (!req)
req = get_reserved_req(fc, file);
- fuse_req_init_context(req);
+ fuse_req_init_context(fc, req);
__set_bit(FR_WAITING, &req->flags);
__clear_bit(FR_BACKGROUND, &req->flags);
return req;
@@ -264,7 +264,7 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
{
- if (atomic_dec_and_test(&req->count)) {
+ if (refcount_dec_and_test(&req->count)) {
if (test_bit(FR_BACKGROUND, &req->flags)) {
/*
* We get here in the unlikely case that a background
@@ -1222,6 +1222,9 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
struct fuse_in *in;
unsigned reqsize;
+ if (task_active_pid_ns(current) != fc->pid_ns)
+ return -EIO;
+
restart:
spin_lock(&fiq->waitq.lock);
err = -EAGAIN;
@@ -1820,6 +1823,9 @@ static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
struct fuse_req *req;
struct fuse_out_header oh;
+ if (task_active_pid_ns(current) != fc->pid_ns)
+ return -EIO;
+
if (nbytes < sizeof(struct fuse_out_header))
return -EINVAL;
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index ec238fb..aa93f09 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -58,7 +58,7 @@ struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
}
INIT_LIST_HEAD(&ff->write_entry);
- atomic_set(&ff->count, 1);
+ refcount_set(&ff->count, 1);
RB_CLEAR_NODE(&ff->polled_node);
init_waitqueue_head(&ff->poll_wait);
@@ -77,7 +77,7 @@ void fuse_file_free(struct fuse_file *ff)
static struct fuse_file *fuse_file_get(struct fuse_file *ff)
{
- atomic_inc(&ff->count);
+ refcount_inc(&ff->count);
return ff;
}
@@ -88,7 +88,7 @@ static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
static void fuse_file_put(struct fuse_file *ff, bool sync)
{
- if (atomic_dec_and_test(&ff->count)) {
+ if (refcount_dec_and_test(&ff->count)) {
struct fuse_req *req = ff->reserved_req;
if (ff->fc->no_open) {
@@ -293,7 +293,7 @@ static int fuse_release(struct inode *inode, struct file *file)
void fuse_sync_release(struct fuse_file *ff, int flags)
{
- WARN_ON(atomic_read(&ff->count) != 1);
+ WARN_ON(refcount_read(&ff->count) > 1);
fuse_prepare_release(ff, flags, FUSE_RELEASE);
/*
* iput(NULL) is a no-op and since the refcount is 1 and everything's
@@ -2083,7 +2083,8 @@ static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma)
return generic_file_mmap(file, vma);
}
-static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
+static int convert_fuse_file_lock(struct fuse_conn *fc,
+ const struct fuse_file_lock *ffl,
struct file_lock *fl)
{
switch (ffl->type) {
@@ -2098,7 +2099,14 @@ static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
fl->fl_start = ffl->start;
fl->fl_end = ffl->end;
- fl->fl_pid = ffl->pid;
+
+ /*
+ * Convert pid into the caller's pid namespace. If the pid
+ * does not map into the namespace fl_pid will get set to 0.
+ */
+ rcu_read_lock();
+ fl->fl_pid = pid_vnr(find_pid_ns(ffl->pid, fc->pid_ns));
+ rcu_read_unlock();
break;
default:
@@ -2147,7 +2155,7 @@ static int fuse_getlk(struct file *file, struct file_lock *fl)
args.out.args[0].value = &outarg;
err = fuse_simple_request(fc, &args);
if (!err)
- err = convert_fuse_file_lock(&outarg.lk, fl);
+ err = convert_fuse_file_lock(fc, &outarg.lk, fl);
return err;
}
@@ -2159,7 +2167,8 @@ static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
FUSE_ARGS(args);
struct fuse_lk_in inarg;
int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
- pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
+ struct pid *pid = fl->fl_type != F_UNLCK ? task_tgid(current) : NULL;
+ pid_t pid_nr = pid_nr_ns(pid, fc->pid_ns);
int err;
if (fl->fl_lmops && fl->fl_lmops->lm_grant) {
@@ -2171,7 +2180,10 @@ static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
if (fl->fl_flags & FL_CLOSE)
return 0;
- fuse_lk_fill(&args, file, fl, opcode, pid, flock, &inarg);
+ if (pid && pid_nr == 0)
+ return -EOVERFLOW;
+
+ fuse_lk_fill(&args, file, fl, opcode, pid_nr, flock, &inarg);
err = fuse_simple_request(fc, &args);
/* locking is restartable */
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index f33341d..1bd7ffd 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -24,6 +24,8 @@
#include <linux/workqueue.h>
#include <linux/kref.h>
#include <linux/xattr.h>
+#include <linux/pid_namespace.h>
+#include <linux/refcount.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
@@ -137,7 +139,7 @@ struct fuse_file {
u64 nodeid;
/** Refcount */
- atomic_t count;
+ refcount_t count;
/** FOPEN_* flags returned by open */
u32 open_flags;
@@ -306,7 +308,7 @@ struct fuse_req {
struct list_head intr_entry;
/** refcount */
- atomic_t count;
+ refcount_t count;
/** Unique ID for the interrupt request */
u64 intr_unique;
@@ -448,7 +450,7 @@ struct fuse_conn {
spinlock_t lock;
/** Refcount */
- atomic_t count;
+ refcount_t count;
/** Number of fuse_dev's */
atomic_t dev_count;
@@ -461,6 +463,9 @@ struct fuse_conn {
/** The group id for this mount */
kgid_t group_id;
+ /** The pid namespace for this mount */
+ struct pid_namespace *pid_ns;
+
/** Maximum read size */
unsigned max_read;
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 73cf051..5a1b58f 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -21,6 +21,7 @@
#include <linux/sched.h>
#include <linux/exportfs.h>
#include <linux/posix_acl.h>
+#include <linux/pid_namespace.h>
MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
MODULE_DESCRIPTION("Filesystem in Userspace");
@@ -601,7 +602,7 @@ void fuse_conn_init(struct fuse_conn *fc)
memset(fc, 0, sizeof(*fc));
spin_lock_init(&fc->lock);
init_rwsem(&fc->killsb);
- atomic_set(&fc->count, 1);
+ refcount_set(&fc->count, 1);
atomic_set(&fc->dev_count, 1);
init_waitqueue_head(&fc->blocked_waitq);
init_waitqueue_head(&fc->reserved_req_waitq);
@@ -619,14 +620,16 @@ void fuse_conn_init(struct fuse_conn *fc)
fc->connected = 1;
fc->attr_version = 1;
get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
+ fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
}
EXPORT_SYMBOL_GPL(fuse_conn_init);
void fuse_conn_put(struct fuse_conn *fc)
{
- if (atomic_dec_and_test(&fc->count)) {
+ if (refcount_dec_and_test(&fc->count)) {
if (fc->destroy_req)
fuse_request_free(fc->destroy_req);
+ put_pid_ns(fc->pid_ns);
fc->release(fc);
}
}
@@ -634,7 +637,7 @@ EXPORT_SYMBOL_GPL(fuse_conn_put);
struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
{
- atomic_inc(&fc->count);
+ refcount_inc(&fc->count);
return fc;
}
EXPORT_SYMBOL_GPL(fuse_conn_get);