From ce623f89872df4253719be71531116751eeab85f Mon Sep 17 00:00:00 2001 From: Aleksa Sarai Date: Sat, 7 Dec 2019 01:13:27 +1100 Subject: [PATCH] nsfs: clean-up ns_get_path() signature to return int ns_get_path() and ns_get_path_cb() only ever return either NULL or an ERR_PTR. It is far more idiomatic to simply return an integer, and it makes all of the callers of ns_get_path() more straightforward to read. Fixes: e149ed2b805f ("take the targets of /proc/*/ns/* symlinks to separate fs") Signed-off-by: Aleksa Sarai Signed-off-by: Al Viro --- fs/nsfs.c | 29 ++++++++++++++--------------- fs/proc/namespaces.c | 6 +++--- include/linux/proc_ns.h | 4 ++-- kernel/bpf/offload.c | 12 ++++++------ kernel/events/core.c | 2 +- 5 files changed, 26 insertions(+), 27 deletions(-) diff --git a/fs/nsfs.c b/fs/nsfs.c index a0431642c6b5..f3d2833c5781 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -52,7 +52,7 @@ 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; @@ -71,13 +71,13 @@ 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); @@ -89,7 +89,7 @@ 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; @@ -98,23 +98,22 @@ 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; } @@ -131,7 +130,7 @@ 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 = { @@ -147,7 +146,7 @@ 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); @@ -164,11 +163,11 @@ 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/proc/namespaces.c b/fs/proc/namespaces.c index dd2b35f78b09..08dd94df1a66 100644 --- a/fs/proc/namespaces.c +++ b/fs/proc/namespaces.c @@ -42,14 +42,14 @@ 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); @@ -57,7 +57,7 @@ static const char *proc_ns_get_link(struct dentry *dentry, nd_jump_link(&ns_path); } put_task_struct(task); - return error; + return ERR_PTR(error); } static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int buflen) diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h index d31cb6215905..aed366b4795c 100644 --- a/include/linux/proc_ns.h +++ b/include/linux/proc_ns.h @@ -76,10 +76,10 @@ static inline int ns_alloc_inum(struct ns_common *ns) extern struct file *proc_ns_fget(int fd); #define get_proc_ns(inode) ((struct ns_common *)(inode)->i_private) -extern void *ns_get_path(struct path *path, struct task_struct *task, +extern int ns_get_path(struct path *path, struct task_struct *task, const struct proc_ns_operations *ns_ops); typedef struct ns_common *ns_get_path_helper_t(void *); -extern void *ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb, +extern int ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb, void *private_data); extern int ns_get_name(char *buf, size_t size, struct task_struct *task, diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index 5b9da0954a27..2c5dc6541ece 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -302,14 +302,14 @@ int bpf_prog_offload_info_fill(struct bpf_prog_info *info, struct inode *ns_inode; struct path ns_path; char __user *uinsns; - void *res; + int res; u32 ulen; res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); - if (IS_ERR(res)) { + if (res) { if (!info->ifindex) return -ENODEV; - return PTR_ERR(res); + return res; } down_read(&bpf_devs_lock); @@ -526,13 +526,13 @@ int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) }; struct inode *ns_inode; struct path ns_path; - void *res; + int res; res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); - if (IS_ERR(res)) { + if (res) { if (!info->ifindex) return -ENODEV; - return PTR_ERR(res); + return res; } ns_inode = ns_path.dentry->d_inode; diff --git a/kernel/events/core.c b/kernel/events/core.c index 4ff86d57f9e5..c0b11b234290 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7495,7 +7495,7 @@ static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, { struct path ns_path; struct inode *ns_inode; - void *error; + int error; error = ns_get_path(&ns_path, task, ns_ops); if (!error) { -- 2.30.2