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Diffstat (limited to 'fs')
-rw-r--r--fs/namei.c199
-rw-r--r--fs/nsfs.c29
-rw-r--r--fs/open.c147
-rw-r--r--fs/proc/base.c3
-rw-r--r--fs/proc/namespaces.c20
5 files changed, 305 insertions, 93 deletions
diff --git a/fs/namei.c b/fs/namei.c
index 4fb61e0754ed..4167109297e0 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -491,7 +491,7 @@ struct nameidata {
struct path root;
struct inode *inode; /* path.dentry.d_inode */
unsigned int flags;
- unsigned seq, m_seq;
+ unsigned seq, m_seq, r_seq;
int last_type;
unsigned depth;
int total_link_count;
@@ -641,6 +641,14 @@ static bool legitimize_links(struct nameidata *nd)
static bool legitimize_root(struct nameidata *nd)
{
+ /*
+ * For scoped-lookups (where nd->root has been zeroed), we need to
+ * restart the whole lookup from scratch -- because set_root() is wrong
+ * for these lookups (nd->dfd is the root, not the filesystem root).
+ */
+ if (!nd->root.mnt && (nd->flags & LOOKUP_IS_SCOPED))
+ return false;
+ /* Nothing to do if nd->root is zero or is managed by the VFS user. */
if (!nd->root.mnt || (nd->flags & LOOKUP_ROOT))
return true;
nd->flags |= LOOKUP_ROOT_GRABBED;
@@ -776,12 +784,37 @@ static int complete_walk(struct nameidata *nd)
int status;
if (nd->flags & LOOKUP_RCU) {
- if (!(nd->flags & LOOKUP_ROOT))
+ /*
+ * We don't want to zero nd->root for scoped-lookups or
+ * externally-managed nd->root.
+ */
+ if (!(nd->flags & (LOOKUP_ROOT | LOOKUP_IS_SCOPED)))
nd->root.mnt = NULL;
if (unlikely(unlazy_walk(nd)))
return -ECHILD;
}
+ if (unlikely(nd->flags & LOOKUP_IS_SCOPED)) {
+ /*
+ * While the guarantee of LOOKUP_IS_SCOPED is (roughly) "don't
+ * ever step outside the root during lookup" and should already
+ * be guaranteed by the rest of namei, we want to avoid a namei
+ * BUG resulting in userspace being given a path that was not
+ * scoped within the root at some point during the lookup.
+ *
+ * So, do a final sanity-check to make sure that in the
+ * worst-case scenario (a complete bypass of LOOKUP_IS_SCOPED)
+ * we won't silently return an fd completely outside of the
+ * requested root to userspace.
+ *
+ * Userspace could move the path outside the root after this
+ * check, but as discussed elsewhere this is not a concern (the
+ * resolved file was inside the root at some point).
+ */
+ if (!path_is_under(&nd->path, &nd->root))
+ return -EXDEV;
+ }
+
if (likely(!(nd->flags & LOOKUP_JUMPED)))
return 0;
@@ -798,10 +831,18 @@ static int complete_walk(struct nameidata *nd)
return status;
}
-static void set_root(struct nameidata *nd)
+static int set_root(struct nameidata *nd)
{
struct fs_struct *fs = current->fs;
+ /*
+ * Jumping to the real root in a scoped-lookup is a BUG in namei, but we
+ * still have to ensure it doesn't happen because it will cause a breakout
+ * from the dirfd.
+ */
+ if (WARN_ON(nd->flags & LOOKUP_IS_SCOPED))
+ return -ENOTRECOVERABLE;
+
if (nd->flags & LOOKUP_RCU) {
unsigned seq;
@@ -814,6 +855,7 @@ static void set_root(struct nameidata *nd)
get_fs_root(fs, &nd->root);
nd->flags |= LOOKUP_ROOT_GRABBED;
}
+ return 0;
}
static void path_put_conditional(struct path *path, struct nameidata *nd)
@@ -837,6 +879,18 @@ static inline void path_to_nameidata(const struct path *path,
static int nd_jump_root(struct nameidata *nd)
{
+ if (unlikely(nd->flags & LOOKUP_BENEATH))
+ return -EXDEV;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV)) {
+ /* Absolute path arguments to path_init() are allowed. */
+ if (nd->path.mnt != NULL && nd->path.mnt != nd->root.mnt)
+ return -EXDEV;
+ }
+ if (!nd->root.mnt) {
+ int error = set_root(nd);
+ if (error)
+ return error;
+ }
if (nd->flags & LOOKUP_RCU) {
struct dentry *d;
nd->path = nd->root;
@@ -859,14 +913,32 @@ static int nd_jump_root(struct nameidata *nd)
* Helper to directly jump to a known parsed path from ->get_link,
* caller must have taken a reference to path beforehand.
*/
-void nd_jump_link(struct path *path)
+int nd_jump_link(struct path *path)
{
+ int error = -ELOOP;
struct nameidata *nd = current->nameidata;
- path_put(&nd->path);
+ if (unlikely(nd->flags & LOOKUP_NO_MAGICLINKS))
+ goto err;
+
+ error = -EXDEV;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV)) {
+ if (nd->path.mnt != path->mnt)
+ goto err;
+ }
+ /* Not currently safe for scoped-lookups. */
+ if (unlikely(nd->flags & LOOKUP_IS_SCOPED))
+ goto err;
+
+ path_put(&nd->path);
nd->path = *path;
nd->inode = nd->path.dentry->d_inode;
nd->flags |= LOOKUP_JUMPED;
+ return 0;
+
+err:
+ path_put(path);
+ return error;
}
static inline void put_link(struct nameidata *nd)
@@ -1050,6 +1122,9 @@ const char *get_link(struct nameidata *nd)
int error;
const char *res;
+ if (unlikely(nd->flags & LOOKUP_NO_SYMLINKS))
+ return ERR_PTR(-ELOOP);
+
if (!(nd->flags & LOOKUP_RCU)) {
touch_atime(&last->link);
cond_resched();
@@ -1084,10 +1159,9 @@ const char *get_link(struct nameidata *nd)
return res;
}
if (*res == '/') {
- if (!nd->root.mnt)
- set_root(nd);
- if (unlikely(nd_jump_root(nd)))
- return ERR_PTR(-ECHILD);
+ error = nd_jump_root(nd);
+ if (unlikely(error))
+ return ERR_PTR(error);
while (unlikely(*++res == '/'))
;
}
@@ -1269,10 +1343,14 @@ static int follow_managed(struct path *path, struct nameidata *nd)
break;
}
- if (need_mntput && path->mnt == mnt)
- mntput(path->mnt);
- if (need_mntput)
- nd->flags |= LOOKUP_JUMPED;
+ if (need_mntput) {
+ if (path->mnt == mnt)
+ mntput(path->mnt);
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV))
+ ret = -EXDEV;
+ else
+ nd->flags |= LOOKUP_JUMPED;
+ }
if (ret == -EISDIR || !ret)
ret = 1;
if (ret > 0 && unlikely(d_flags_negative(flags)))
@@ -1333,6 +1411,8 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
mounted = __lookup_mnt(path->mnt, path->dentry);
if (!mounted)
break;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV))
+ return false;
path->mnt = &mounted->mnt;
path->dentry = mounted->mnt.mnt_root;
nd->flags |= LOOKUP_JUMPED;
@@ -1353,8 +1433,11 @@ static int follow_dotdot_rcu(struct nameidata *nd)
struct inode *inode = nd->inode;
while (1) {
- if (path_equal(&nd->path, &nd->root))
+ if (path_equal(&nd->path, &nd->root)) {
+ if (unlikely(nd->flags & LOOKUP_BENEATH))
+ return -ECHILD;
break;
+ }
if (nd->path.dentry != nd->path.mnt->mnt_root) {
struct dentry *old = nd->path.dentry;
struct dentry *parent = old->d_parent;
@@ -1367,7 +1450,7 @@ static int follow_dotdot_rcu(struct nameidata *nd)
nd->path.dentry = parent;
nd->seq = seq;
if (unlikely(!path_connected(&nd->path)))
- return -ENOENT;
+ return -ECHILD;
break;
} else {
struct mount *mnt = real_mount(nd->path.mnt);
@@ -1379,6 +1462,8 @@ static int follow_dotdot_rcu(struct nameidata *nd)
return -ECHILD;
if (&mparent->mnt == nd->path.mnt)
break;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV))
+ return -ECHILD;
/* we know that mountpoint was pinned */
nd->path.dentry = mountpoint;
nd->path.mnt = &mparent->mnt;
@@ -1393,6 +1478,8 @@ static int follow_dotdot_rcu(struct nameidata *nd)
return -ECHILD;
if (!mounted)
break;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV))
+ return -ECHILD;
nd->path.mnt = &mounted->mnt;
nd->path.dentry = mounted->mnt.mnt_root;
inode = nd->path.dentry->d_inode;
@@ -1480,9 +1567,12 @@ static int path_parent_directory(struct path *path)
static int follow_dotdot(struct nameidata *nd)
{
- while(1) {
- if (path_equal(&nd->path, &nd->root))
+ while (1) {
+ if (path_equal(&nd->path, &nd->root)) {
+ if (unlikely(nd->flags & LOOKUP_BENEATH))
+ return -EXDEV;
break;
+ }
if (nd->path.dentry != nd->path.mnt->mnt_root) {
int ret = path_parent_directory(&nd->path);
if (ret)
@@ -1491,6 +1581,8 @@ static int follow_dotdot(struct nameidata *nd)
}
if (!follow_up(&nd->path))
break;
+ if (unlikely(nd->flags & LOOKUP_NO_XDEV))
+ return -EXDEV;
}
follow_mount(&nd->path);
nd->inode = nd->path.dentry->d_inode;
@@ -1699,12 +1791,33 @@ static inline int may_lookup(struct nameidata *nd)
static inline int handle_dots(struct nameidata *nd, int type)
{
if (type == LAST_DOTDOT) {
- if (!nd->root.mnt)
- set_root(nd);
- if (nd->flags & LOOKUP_RCU) {
- return follow_dotdot_rcu(nd);
- } else
- return follow_dotdot(nd);
+ int error = 0;
+
+ if (!nd->root.mnt) {
+ error = set_root(nd);
+ if (error)
+ return error;
+ }
+ if (nd->flags & LOOKUP_RCU)
+ error = follow_dotdot_rcu(nd);
+ else
+ error = follow_dotdot(nd);
+ if (error)
+ return error;
+
+ if (unlikely(nd->flags & LOOKUP_IS_SCOPED)) {
+ /*
+ * If there was a racing rename or mount along our
+ * path, then we can't be sure that ".." hasn't jumped
+ * above nd->root (and so userspace should retry or use
+ * some fallback).
+ */
+ smp_rmb();
+ if (unlikely(__read_seqcount_retry(&mount_lock.seqcount, nd->m_seq)))
+ return -EAGAIN;
+ if (unlikely(__read_seqcount_retry(&rename_lock.seqcount, nd->r_seq)))
+ return -EAGAIN;
+ }
}
return 0;
}
@@ -2158,6 +2271,7 @@ OK:
/* must be paired with terminate_walk() */
static const char *path_init(struct nameidata *nd, unsigned flags)
{
+ int error;
const char *s = nd->name->name;
if (!*s)
@@ -2168,6 +2282,11 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
nd->last_type = LAST_ROOT; /* if there are only slashes... */
nd->flags = flags | LOOKUP_JUMPED | LOOKUP_PARENT;
nd->depth = 0;
+
+ nd->m_seq = __read_seqcount_begin(&mount_lock.seqcount);
+ nd->r_seq = __read_seqcount_begin(&rename_lock.seqcount);
+ smp_rmb();
+
if (flags & LOOKUP_ROOT) {
struct dentry *root = nd->root.dentry;
struct inode *inode = root->d_inode;
@@ -2176,9 +2295,8 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
nd->path = nd->root;
nd->inode = inode;
if (flags & LOOKUP_RCU) {
- nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
+ nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
nd->root_seq = nd->seq;
- nd->m_seq = read_seqbegin(&mount_lock);
} else {
path_get(&nd->path);
}
@@ -2189,13 +2307,16 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
nd->path.mnt = NULL;
nd->path.dentry = NULL;
- nd->m_seq = read_seqbegin(&mount_lock);
- if (*s == '/') {
- set_root(nd);
- if (likely(!nd_jump_root(nd)))
- return s;
- return ERR_PTR(-ECHILD);
- } else if (nd->dfd == AT_FDCWD) {
+ /* Absolute pathname -- fetch the root (LOOKUP_IN_ROOT uses nd->dfd). */
+ if (*s == '/' && !(flags & LOOKUP_IN_ROOT)) {
+ error = nd_jump_root(nd);
+ if (unlikely(error))
+ return ERR_PTR(error);
+ return s;
+ }
+
+ /* Relative pathname -- get the starting-point it is relative to. */
+ if (nd->dfd == AT_FDCWD) {
if (flags & LOOKUP_RCU) {
struct fs_struct *fs = current->fs;
unsigned seq;
@@ -2210,7 +2331,6 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
get_fs_pwd(current->fs, &nd->path);
nd->inode = nd->path.dentry->d_inode;
}
- return s;
} else {
/* Caller must check execute permissions on the starting path component */
struct fd f = fdget_raw(nd->dfd);
@@ -2235,8 +2355,19 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
nd->inode = nd->path.dentry->d_inode;
}
fdput(f);
- return s;
}
+
+ /* For scoped-lookups we need to set the root to the dirfd as well. */
+ if (flags & LOOKUP_IS_SCOPED) {
+ nd->root = nd->path;
+ if (flags & LOOKUP_RCU) {
+ nd->root_seq = nd->seq;
+ } else {
+ path_get(&nd->root);
+ nd->flags |= LOOKUP_ROOT_GRABBED;
+ }
+ }
+ return s;
}
static const char *trailing_symlink(struct nameidata *nd)
diff --git a/fs/nsfs.c b/fs/nsfs.c
index f75767bd623a..b13bfd406820 100644
--- a/fs/nsfs.c
+++ b/fs/nsfs.c
@@ -55,7 +55,7 @@ static void nsfs_evict(struct inode *inode)
ns->ops->put(ns);
}
-static void *__ns_get_path(struct path *path, struct ns_common *ns)
+static int __ns_get_path(struct path *path, struct ns_common *ns)
{
struct vfsmount *mnt = nsfs_mnt;
struct dentry *dentry;
@@ -74,13 +74,13 @@ static void *__ns_get_path(struct path *path, struct ns_common *ns)
got_it:
path->mnt = mntget(mnt);
path->dentry = dentry;
- return NULL;
+ return 0;
slow:
rcu_read_unlock();
inode = new_inode_pseudo(mnt->mnt_sb);
if (!inode) {
ns->ops->put(ns);
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
}
inode->i_ino = ns->inum;
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
@@ -92,7 +92,7 @@ slow:
dentry = d_alloc_anon(mnt->mnt_sb);
if (!dentry) {
iput(inode);
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
}
d_instantiate(dentry, inode);
dentry->d_fsdata = (void *)ns->ops;
@@ -101,23 +101,22 @@ slow:
d_delete(dentry); /* make sure ->d_prune() does nothing */
dput(dentry);
cpu_relax();
- return ERR_PTR(-EAGAIN);
+ return -EAGAIN;
}
goto got_it;
}
-void *ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,
+int ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,
void *private_data)
{
- void *ret;
+ int ret;
do {
struct ns_common *ns = ns_get_cb(private_data);
if (!ns)
- return ERR_PTR(-ENOENT);
-
+ return -ENOENT;
ret = __ns_get_path(path, ns);
- } while (ret == ERR_PTR(-EAGAIN));
+ } while (ret == -EAGAIN);
return ret;
}
@@ -134,7 +133,7 @@ static struct ns_common *ns_get_path_task(void *private_data)
return args->ns_ops->get(args->task);
}
-void *ns_get_path(struct path *path, struct task_struct *task,
+int ns_get_path(struct path *path, struct task_struct *task,
const struct proc_ns_operations *ns_ops)
{
struct ns_get_path_task_args args = {
@@ -150,7 +149,7 @@ int open_related_ns(struct ns_common *ns,
{
struct path path = {};
struct file *f;
- void *err;
+ int err;
int fd;
fd = get_unused_fd_flags(O_CLOEXEC);
@@ -167,11 +166,11 @@ int open_related_ns(struct ns_common *ns,
}
err = __ns_get_path(&path, relative);
- } while (err == ERR_PTR(-EAGAIN));
+ } while (err == -EAGAIN);
- if (IS_ERR(err)) {
+ if (err) {
put_unused_fd(fd);
- return PTR_ERR(err);
+ return err;
}
f = dentry_open(&path, O_RDONLY, current_cred());
diff --git a/fs/open.c b/fs/open.c
index b62f5c0923a8..8cdb2b675867 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -955,48 +955,84 @@ struct file *open_with_fake_path(const struct path *path, int flags,
}
EXPORT_SYMBOL(open_with_fake_path);
-static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
+#define WILL_CREATE(flags) (flags & (O_CREAT | __O_TMPFILE))
+#define O_PATH_FLAGS (O_DIRECTORY | O_NOFOLLOW | O_PATH | O_CLOEXEC)
+
+static inline struct open_how build_open_how(int flags, umode_t mode)
+{
+ struct open_how how = {
+ .flags = flags & VALID_OPEN_FLAGS,
+ .mode = mode & S_IALLUGO,
+ };
+
+ /* O_PATH beats everything else. */
+ if (how.flags & O_PATH)
+ how.flags &= O_PATH_FLAGS;
+ /* Modes should only be set for create-like flags. */
+ if (!WILL_CREATE(how.flags))
+ how.mode = 0;
+ return how;
+}
+
+static inline int build_open_flags(const struct open_how *how,
+ struct open_flags *op)
{
+ int flags = how->flags;
int lookup_flags = 0;
int acc_mode = ACC_MODE(flags);
+ /* Must never be set by userspace */
+ flags &= ~(FMODE_NONOTIFY | O_CLOEXEC);
+
/*
- * Clear out all open flags we don't know about so that we don't report
- * them in fcntl(F_GETFD) or similar interfaces.
+ * Older syscalls implicitly clear all of the invalid flags or argument
+ * values before calling build_open_flags(), but openat2(2) checks all
+ * of its arguments.
*/
- flags &= VALID_OPEN_FLAGS;
+ if (flags & ~VALID_OPEN_FLAGS)
+ return -EINVAL;
+ if (how->resolve & ~VALID_RESOLVE_FLAGS)
+ return -EINVAL;
- if (flags & (O_CREAT | __O_TMPFILE))
- op->mode = (mode & S_IALLUGO) | S_IFREG;
- else
+ /* Deal with the mode. */
+ if (WILL_CREATE(flags)) {
+ if (how->mode & ~S_IALLUGO)
+ return -EINVAL;
+ op->mode = how->mode | S_IFREG;
+ } else {
+ if (how->mode != 0)
+ return -EINVAL;
op->mode = 0;
-
- /* Must never be set by userspace */
- flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC;
+ }
/*
- * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
- * check for O_DSYNC if the need any syncing at all we enforce it's
- * always set instead of having to deal with possibly weird behaviour
- * for malicious applications setting only __O_SYNC.
+ * In order to ensure programs get explicit errors when trying to use
+ * O_TMPFILE on old kernels, O_TMPFILE is implemented such that it
+ * looks like (O_DIRECTORY|O_RDWR & ~O_CREAT) to old kernels. But we
+ * have to require userspace to explicitly set it.
*/
- if (flags & __O_SYNC)
- flags |= O_DSYNC;
-
if (flags & __O_TMPFILE) {
if ((flags & O_TMPFILE_MASK) != O_TMPFILE)
return -EINVAL;
if (!(acc_mode & MAY_WRITE))
return -EINVAL;
- } else if (flags & O_PATH) {
- /*
- * If we have O_PATH in the open flag. Then we
- * cannot have anything other than the below set of flags
- */
- flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH;
+ }
+ if (flags & O_PATH) {
+ /* O_PATH only permits certain other flags to be set. */
+ if (flags & ~O_PATH_FLAGS)
+ return -EINVAL;
acc_mode = 0;
}
+ /*
+ * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
+ * check for O_DSYNC if the need any syncing at all we enforce it's
+ * always set instead of having to deal with possibly weird behaviour
+ * for malicious applications setting only __O_SYNC.
+ */
+ if (flags & __O_SYNC)
+ flags |= O_DSYNC;
+
op->open_flag = flags;
/* O_TRUNC implies we need access checks for write permissions */
@@ -1022,6 +1058,18 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o
lookup_flags |= LOOKUP_DIRECTORY;
if (!(flags & O_NOFOLLOW))
lookup_flags |= LOOKUP_FOLLOW;
+
+ if (how->resolve & RESOLVE_NO_XDEV)
+ lookup_flags |= LOOKUP_NO_XDEV;
+ if (how->resolve & RESOLVE_NO_MAGICLINKS)
+ lookup_flags |= LOOKUP_NO_MAGICLINKS;
+ if (how->resolve & RESOLVE_NO_SYMLINKS)
+ lookup_flags |= LOOKUP_NO_SYMLINKS;
+ if (how->resolve & RESOLVE_BENEATH)
+ lookup_flags |= LOOKUP_BENEATH;
+ if (how->resolve & RESOLVE_IN_ROOT)
+ lookup_flags |= LOOKUP_IN_ROOT;
+
op->lookup_flags = lookup_flags;
return 0;
}
@@ -1040,8 +1088,11 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o
struct file *file_open_name(struct filename *name, int flags, umode_t mode)
{
struct open_flags op;
- int err = build_open_flags(flags, mode, &op);
- return err ? ERR_PTR(err) : do_filp_open(AT_FDCWD, name, &op);
+ struct open_how how = build_open_how(flags, mode);
+ int err = build_open_flags(&how, &op);
+ if (err)
+ return ERR_PTR(err);
+ return do_filp_open(AT_FDCWD, name, &op);
}
/**
@@ -1072,17 +1123,19 @@ struct file *file_open_root(struct dentry *dentry, struct vfsmount *mnt,
const char *filename, int flags, umode_t mode)
{
struct open_flags op;
- int err = build_open_flags(flags, mode, &op);
+ struct open_how how = build_open_how(flags, mode);
+ int err = build_open_flags(&how, &op);
if (err)
return ERR_PTR(err);
return do_file_open_root(dentry, mnt, filename, &op);
}
EXPORT_SYMBOL(file_open_root);
-long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)
+static long do_sys_openat2(int dfd, const char __user *filename,
+ struct open_how *how)
{
struct open_flags op;
- int fd = build_open_flags(flags, mode, &op);
+ int fd = build_open_flags(how, &op);
struct filename *tmp;
if (fd)
@@ -1092,7 +1145,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)
if (IS_ERR(tmp))
return PTR_ERR(tmp);
- fd = get_unused_fd_flags(flags);
+ fd = get_unused_fd_flags(how->flags);
if (fd >= 0) {
struct file *f = do_filp_open(dfd, tmp, &op);
if (IS_ERR(f)) {
@@ -1107,12 +1160,16 @@ long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)
return fd;
}
-SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode)
+long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)
{
- if (force_o_largefile())
- flags |= O_LARGEFILE;
+ struct open_how how = build_open_how(flags, mode);
+ return do_sys_openat2(dfd, filename, &how);
+}
- return do_sys_open(AT_FDCWD, filename, flags, mode);
+
+SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode)
+{
+ return ksys_open(filename, flags, mode);
}
SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags,
@@ -1120,10 +1177,32 @@ SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags,
{
if (force_o_largefile())
flags |= O_LARGEFILE;
-
return do_sys_open(dfd, filename, flags, mode);
}
+SYSCALL_DEFINE4(openat2, int, dfd, const char __user *, filename,
+ struct open_how __user *, how, size_t, usize)
+{
+ int err;
+ struct open_how tmp;
+
+ BUILD_BUG_ON(sizeof(struct open_how) < OPEN_HOW_SIZE_VER0);
+ BUILD_BUG_ON(sizeof(struct open_how) != OPEN_HOW_SIZE_LATEST);
+
+ if (unlikely(usize < OPEN_HOW_SIZE_VER0))
+ return -EINVAL;
+
+ err = copy_struct_from_user(&tmp, sizeof(tmp), how, usize);
+ if (err)
+ return err;
+
+ /* O_LARGEFILE is only allowed for non-O_PATH. */
+ if (!(tmp.flags & O_PATH) && force_o_largefile())
+ tmp.flags |= O_LARGEFILE;
+
+ return do_sys_openat2(dfd, filename, &tmp);
+}
+
#ifdef CONFIG_COMPAT
/*
* Exactly like sys_open(), except that it doesn't set the
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 915686772f0e..c7c64272b0fa 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1718,8 +1718,7 @@ static const char *proc_pid_get_link(struct dentry *dentry,
if (error)
goto out;
- nd_jump_link(&path);
- return NULL;
+ error = nd_jump_link(&path);
out:
return ERR_PTR(error);
}
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index 8b5c720fe5d7..8e159fc78c0a 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -46,22 +46,26 @@ static const char *proc_ns_get_link(struct dentry *dentry,
const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
struct task_struct *task;
struct path ns_path;
- void *error = ERR_PTR(-EACCES);
+ int error = -EACCES;
if (!dentry)
return ERR_PTR(-ECHILD);
task = get_proc_task(inode);
if (!task)
- return error;
+ return ERR_PTR(-EACCES);
- if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
- error = ns_get_path(&ns_path, task, ns_ops);
- if (!error)
- nd_jump_link(&ns_path);
- }
+ if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
+ goto out;
+
+ error = ns_get_path(&ns_path, task, ns_ops);
+ if (error)
+ goto out;
+
+ error = nd_jump_link(&ns_path);
+out:
put_task_struct(task);
- return error;
+ return ERR_PTR(error);
}
static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int buflen)