From 7cb537b6f6d7d6529be04139178f929d9a63b918 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 26 Nov 2023 02:08:34 +0000 Subject: [PATCH 1/7] file: massage cleanup of files that failed to open A file that has never gotten FMODE_OPENED will never have RCU-accessed references, its final fput() is equivalent to file_free() and if it doesn't have FMODE_BACKING either, it can be done from any context and won't need task_work treatment. Now that we have SLAB_TYPESAFE_BY_RCU we can simplify this and have other callers benefit. All of that can be achieved easier is to make fput() recoginze that case and call file_free() directly. No need to introduce a special primitive for that. It also allowed things like failing dentry_open() could benefit from that as well. Signed-off-by: Al Viro [Christian Brauner : massage commit message] Link: https://lore.kernel.org/r/20231126020834.GC38156@ZenIV Signed-off-by: Christian Brauner --- fs/file_table.c | 16 ++++------------ fs/internal.h | 1 - fs/namei.c | 5 +---- 3 files changed, 5 insertions(+), 17 deletions(-) diff --git a/fs/file_table.c b/fs/file_table.c index de4a2915bfd4..6deac386486d 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -75,18 +75,6 @@ static inline void file_free(struct file *f) } } -void release_empty_file(struct file *f) -{ - WARN_ON_ONCE(f->f_mode & (FMODE_BACKING | FMODE_OPENED)); - if (atomic_long_dec_and_test(&f->f_count)) { - security_file_free(f); - put_cred(f->f_cred); - if (likely(!(f->f_mode & FMODE_NOACCOUNT))) - percpu_counter_dec(&nr_files); - kmem_cache_free(filp_cachep, f); - } -} - /* * Return the total number of open files in the system */ @@ -445,6 +433,10 @@ void fput(struct file *file) if (atomic_long_dec_and_test(&file->f_count)) { struct task_struct *task = current; + if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) { + file_free(file); + return; + } if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { init_task_work(&file->f_rcuhead, ____fput); if (!task_work_add(task, &file->f_rcuhead, TWA_RESUME)) diff --git a/fs/internal.h b/fs/internal.h index 58e43341aebf..273e6fd40d1b 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -94,7 +94,6 @@ extern void chroot_fs_refs(const struct path *, const struct path *); struct file *alloc_empty_file(int flags, const struct cred *cred); struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred); struct file *alloc_empty_backing_file(int flags, const struct cred *cred); -void release_empty_file(struct file *f); static inline void file_put_write_access(struct file *file) { diff --git a/fs/namei.c b/fs/namei.c index 71c13b2990b4..f0ead1858267 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3785,10 +3785,7 @@ static struct file *path_openat(struct nameidata *nd, WARN_ON(1); error = -EINVAL; } - if (unlikely(file->f_mode & FMODE_OPENED)) - fput(file); - else - release_empty_file(file); + fput(file); if (error == -EOPENSTALE) { if (flags & LOOKUP_RCU) error = -ECHILD; From 253ca8678d30bcf94410b54476fc1e0f1627a137 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 26 Nov 2023 12:24:38 -0800 Subject: [PATCH 2/7] Improve __fget_files_rcu() code generation (and thus __fget_light()) Commit 0ede61d8589c ("file: convert to SLAB_TYPESAFE_BY_RCU") caused a performance regression as reported by the kernel test robot. The __fget_light() function is one of those critical ones for some loads, and the code generation was unnecessarily impacted. Let's just write that function to better. Reported-by: kernel test robot Cc: Christian Brauner Cc: Jann Horn Cc: Mateusz Guzik Closes: https://lore.kernel.org/oe-lkp/202311201406.2022ca3f-oliver.sang@intel.com Signed-off-by: Linus Torvalds Link: https://lore.kernel.org/r/CAHk-=wiCJtLbFWNURB34b9a_R_unaH3CiMRXfkR0-iihB_z68A@mail.gmail.com Signed-off-by: Christian Brauner --- fs/file.c | 53 ++++++++++++++++++++++++++--------------- include/linux/fdtable.h | 15 ++++++++---- 2 files changed, 44 insertions(+), 24 deletions(-) diff --git a/fs/file.c b/fs/file.c index 5fb0b146e79e..50df31e104a5 100644 --- a/fs/file.c +++ b/fs/file.c @@ -959,31 +959,45 @@ static inline struct file *__fget_files_rcu(struct files_struct *files, struct file *file; struct fdtable *fdt = rcu_dereference_raw(files->fdt); struct file __rcu **fdentry; + unsigned long nospec_mask; - if (unlikely(fd >= fdt->max_fds)) - return NULL; - - fdentry = fdt->fd + array_index_nospec(fd, fdt->max_fds); + /* Mask is a 0 for invalid fd's, ~0 for valid ones */ + nospec_mask = array_index_mask_nospec(fd, fdt->max_fds); /* - * Ok, we have a file pointer. However, because we do - * this all locklessly under RCU, we may be racing with - * that file being closed. + * fdentry points to the 'fd' offset, or fdt->fd[0]. + * Loading from fdt->fd[0] is always safe, because the + * array always exists. + */ + fdentry = fdt->fd + (fd & nospec_mask); + + /* Do the load, then mask any invalid result */ + file = rcu_dereference_raw(*fdentry); + file = (void *)(nospec_mask & (unsigned long)file); + if (unlikely(!file)) + return NULL; + + /* + * Ok, we have a file pointer that was valid at + * some point, but it might have become stale since. * + * We need to confirm it by incrementing the refcount + * and then check the lookup again. + * + * atomic_long_inc_not_zero() gives us a full memory + * barrier. We only really need an 'acquire' one to + * protect the loads below, but we don't have that. + */ + if (unlikely(!atomic_long_inc_not_zero(&file->f_count))) + continue; + + /* * Such a race can take two forms: * * (a) the file ref already went down to zero and the * file hasn't been reused yet or the file count * isn't zero but the file has already been reused. - */ - file = __get_file_rcu(fdentry); - if (unlikely(!file)) - return NULL; - - if (unlikely(IS_ERR(file))) - continue; - - /* + * * (b) the file table entry has changed under us. * Note that we don't need to re-check the 'fdt->fd' * pointer having changed, because it always goes @@ -991,7 +1005,8 @@ static inline struct file *__fget_files_rcu(struct files_struct *files, * * If so, we need to put our ref and try again. */ - if (unlikely(rcu_dereference_raw(files->fdt) != fdt)) { + if (unlikely(file != rcu_dereference_raw(*fdentry)) || + unlikely(rcu_dereference_raw(files->fdt) != fdt)) { fput(file); continue; } @@ -1128,13 +1143,13 @@ static unsigned long __fget_light(unsigned int fd, fmode_t mask) * atomic_read_acquire() pairs with atomic_dec_and_test() in * put_files_struct(). */ - if (atomic_read_acquire(&files->count) == 1) { + if (likely(atomic_read_acquire(&files->count) == 1)) { file = files_lookup_fd_raw(files, fd); if (!file || unlikely(file->f_mode & mask)) return 0; return (unsigned long)file; } else { - file = __fget(fd, mask); + file = __fget_files(files, fd, mask); if (!file) return 0; return FDPUT_FPUT | (unsigned long)file; diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index bc4c3287a65e..80bd7789bab1 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -83,12 +83,17 @@ struct dentry; static inline struct file *files_lookup_fd_raw(struct files_struct *files, unsigned int fd) { struct fdtable *fdt = rcu_dereference_raw(files->fdt); + unsigned long mask = array_index_mask_nospec(fd, fdt->max_fds); + struct file *needs_masking; - if (fd < fdt->max_fds) { - fd = array_index_nospec(fd, fdt->max_fds); - return rcu_dereference_raw(fdt->fd[fd]); - } - return NULL; + /* + * 'mask' is zero for an out-of-bounds fd, all ones for ok. + * 'fd&mask' is 'fd' for ok, or 0 for out of bounds. + * + * Accessing fdt->fd[0] is ok, but needs masking of the result. + */ + needs_masking = rcu_dereference_raw(fdt->fd[fd&mask]); + return (struct file *)(mask & (unsigned long)needs_masking); } static inline struct file *files_lookup_fd_locked(struct files_struct *files, unsigned int fd) From a88c955fcfb49727d0ed86b47410f6555a8e69e4 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Nov 2023 13:49:07 +0100 Subject: [PATCH 3/7] file: s/close_fd_get_file()/file_close_fd()/g That really shouldn't have "get" in there as that implies we're bumping the reference count which we don't do at all. We used to but not anmore. Now we're just closing the fd and pick that file from the fdtable without bumping the reference count. Update the wrong documentation while at it. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-1-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner --- drivers/android/binder.c | 2 +- fs/file.c | 14 +++++++++----- fs/open.c | 2 +- include/linux/fdtable.h | 2 +- 4 files changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 92128aae2d06..7658103ba760 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -1921,7 +1921,7 @@ static void binder_deferred_fd_close(int fd) if (!twcb) return; init_task_work(&twcb->twork, binder_do_fd_close); - twcb->file = close_fd_get_file(fd); + twcb->file = file_close_fd(fd); if (twcb->file) { // pin it until binder_do_fd_close(); see comments there get_file(twcb->file); diff --git a/fs/file.c b/fs/file.c index 50df31e104a5..66f04442a384 100644 --- a/fs/file.c +++ b/fs/file.c @@ -796,7 +796,7 @@ int __close_range(unsigned fd, unsigned max_fd, unsigned int flags) } /* - * See close_fd_get_file() below, this variant assumes current->files->file_lock + * See file_close_fd() below, this variant assumes current->files->file_lock * is held. */ struct file *__close_fd_get_file(unsigned int fd) @@ -804,11 +804,15 @@ struct file *__close_fd_get_file(unsigned int fd) return pick_file(current->files, fd); } -/* - * variant of close_fd that gets a ref on the file for later fput. - * The caller must ensure that filp_close() called on the file. +/** + * file_close_fd - return file associated with fd + * @fd: file descriptor to retrieve file for + * + * Doesn't take a separate reference count. + * + * Returns: The file associated with @fd (NULL if @fd is not open) */ -struct file *close_fd_get_file(unsigned int fd) +struct file *file_close_fd(unsigned int fd) { struct files_struct *files = current->files; struct file *file; diff --git a/fs/open.c b/fs/open.c index 02dc608d40d8..48775329f3f1 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1577,7 +1577,7 @@ SYSCALL_DEFINE1(close, unsigned int, fd) int retval; struct file *file; - file = close_fd_get_file(fd); + file = file_close_fd(fd); if (!file) return -EBADF; diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index 80bd7789bab1..78c8326d74ae 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -119,7 +119,7 @@ int iterate_fd(struct files_struct *, unsigned, extern int close_fd(unsigned int fd); extern int __close_range(unsigned int fd, unsigned int max_fd, unsigned int flags); -extern struct file *close_fd_get_file(unsigned int fd); +extern struct file *file_close_fd(unsigned int fd); extern int unshare_fd(unsigned long unshare_flags, unsigned int max_fds, struct files_struct **new_fdp); From 24fa3ae9467f49dd9698fd884f2c6b13cc8ea12d Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Nov 2023 13:49:08 +0100 Subject: [PATCH 4/7] file: remove pointless wrapper Only io_uring uses __close_fd_get_file(). All it does is hide current->files but io_uring accesses files_struct directly right now anyway so it's a bit pointless. Just rename pick_file() to file_close_fd_locked() and let io_uring use it. Add a lockdep assert in there that we expect the caller to hold file_lock while we're at it. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-2-e73ca6f4ea83@kernel.org Reviewed-by: Jens Axboe Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- fs/file.c | 23 +++++++++-------------- fs/internal.h | 2 +- io_uring/openclose.c | 2 +- 3 files changed, 11 insertions(+), 16 deletions(-) diff --git a/fs/file.c b/fs/file.c index 66f04442a384..c8eaa0b29a08 100644 --- a/fs/file.c +++ b/fs/file.c @@ -629,19 +629,23 @@ void fd_install(unsigned int fd, struct file *file) EXPORT_SYMBOL(fd_install); /** - * pick_file - return file associatd with fd + * file_close_fd_locked - return file associated with fd * @files: file struct to retrieve file from * @fd: file descriptor to retrieve file for * + * Doesn't take a separate reference count. + * * Context: files_lock must be held. * * Returns: The file associated with @fd (NULL if @fd is not open) */ -static struct file *pick_file(struct files_struct *files, unsigned fd) +struct file *file_close_fd_locked(struct files_struct *files, unsigned fd) { struct fdtable *fdt = files_fdtable(files); struct file *file; + lockdep_assert_held(&files->file_lock); + if (fd >= fdt->max_fds) return NULL; @@ -660,7 +664,7 @@ int close_fd(unsigned fd) struct file *file; spin_lock(&files->file_lock); - file = pick_file(files, fd); + file = file_close_fd_locked(files, fd); spin_unlock(&files->file_lock); if (!file) return -EBADF; @@ -707,7 +711,7 @@ static inline void __range_close(struct files_struct *files, unsigned int fd, max_fd = min(max_fd, n); for (; fd <= max_fd; fd++) { - file = pick_file(files, fd); + file = file_close_fd_locked(files, fd); if (file) { spin_unlock(&files->file_lock); filp_close(file, files); @@ -795,15 +799,6 @@ int __close_range(unsigned fd, unsigned max_fd, unsigned int flags) return 0; } -/* - * See file_close_fd() below, this variant assumes current->files->file_lock - * is held. - */ -struct file *__close_fd_get_file(unsigned int fd) -{ - return pick_file(current->files, fd); -} - /** * file_close_fd - return file associated with fd * @fd: file descriptor to retrieve file for @@ -818,7 +813,7 @@ struct file *file_close_fd(unsigned int fd) struct file *file; spin_lock(&files->file_lock); - file = pick_file(files, fd); + file = file_close_fd_locked(files, fd); spin_unlock(&files->file_lock); return file; diff --git a/fs/internal.h b/fs/internal.h index 273e6fd40d1b..a7469ddba9b6 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -179,7 +179,7 @@ extern struct file *do_file_open_root(const struct path *, const char *, const struct open_flags *); extern struct open_how build_open_how(int flags, umode_t mode); extern int build_open_flags(const struct open_how *how, struct open_flags *op); -extern struct file *__close_fd_get_file(unsigned int fd); +struct file *file_close_fd_locked(struct files_struct *files, unsigned fd); long do_sys_ftruncate(unsigned int fd, loff_t length, int small); int chmod_common(const struct path *path, umode_t mode); diff --git a/io_uring/openclose.c b/io_uring/openclose.c index fb73adb89067..74fc22461f48 100644 --- a/io_uring/openclose.c +++ b/io_uring/openclose.c @@ -241,7 +241,7 @@ int io_close(struct io_kiocb *req, unsigned int issue_flags) return -EAGAIN; } - file = __close_fd_get_file(close->fd); + file = file_close_fd_locked(files, close->fd); spin_unlock(&files->file_lock); if (!file) goto err; From 372a34e66fb7f95124fadae9c600b231c35696a7 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Nov 2023 13:49:09 +0100 Subject: [PATCH 5/7] fs: replace f_rcuhead with f_task_work The naming is actively misleading since we switched to SLAB_TYPESAFE_BY_RCU. rcu_head is #define callback_head. Use callback_head directly and rename f_rcuhead to f_task_work. Add comments in there to explain what it's used for. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-3-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner --- fs/file_table.c | 6 +++--- include/linux/fs.h | 4 +++- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/file_table.c b/fs/file_table.c index 6deac386486d..3ba764d73fc9 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -407,7 +407,7 @@ static void delayed_fput(struct work_struct *unused) static void ____fput(struct callback_head *work) { - __fput(container_of(work, struct file, f_rcuhead)); + __fput(container_of(work, struct file, f_task_work)); } /* @@ -438,8 +438,8 @@ void fput(struct file *file) return; } if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { - init_task_work(&file->f_rcuhead, ____fput); - if (!task_work_add(task, &file->f_rcuhead, TWA_RESUME)) + init_task_work(&file->f_task_work, ____fput); + if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) return; /* * After this task has run exit_task_work(), diff --git a/include/linux/fs.h b/include/linux/fs.h index 98b7a7a8c42e..354fd02e0e11 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -991,8 +991,10 @@ static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index) */ struct file { union { + /* fput() uses task work when closing and freeing file (default). */ + struct callback_head f_task_work; + /* fput() must use workqueue (most kernel threads). */ struct llist_node f_llist; - struct rcu_head f_rcuhead; unsigned int f_iocb_flags; }; From eac9189c96196574a83a553ca5a7543dd9f5fe3e Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Nov 2023 13:49:10 +0100 Subject: [PATCH 6/7] file: stop exposing receive_fd_user() Not every subsystem needs to have their own specialized helper. Just us the __receive_fd() helper. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-4-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner --- include/linux/file.h | 7 ------- include/net/scm.h | 9 +++++++++ net/compat.c | 2 +- net/core/scm.c | 2 +- 4 files changed, 11 insertions(+), 9 deletions(-) diff --git a/include/linux/file.h b/include/linux/file.h index 6e9099d29343..c0d5219c2852 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -101,13 +101,6 @@ extern int __receive_fd(struct file *file, int __user *ufd, extern int receive_fd(struct file *file, unsigned int o_flags); -static inline int receive_fd_user(struct file *file, int __user *ufd, - unsigned int o_flags) -{ - if (ufd == NULL) - return -EFAULT; - return __receive_fd(file, ufd, o_flags); -} int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags); extern void flush_delayed_fput(void); diff --git a/include/net/scm.h b/include/net/scm.h index e8c76b4be2fe..8aae2468bae0 100644 --- a/include/net/scm.h +++ b/include/net/scm.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -208,5 +209,13 @@ static inline void scm_recv_unix(struct socket *sock, struct msghdr *msg, scm_destroy_cred(scm); } +static inline int scm_recv_one_fd(struct file *f, int __user *ufd, + unsigned int flags) +{ + if (!ufd) + return -EFAULT; + return __receive_fd(f, ufd, flags); +} + #endif /* __LINUX_NET_SCM_H */ diff --git a/net/compat.c b/net/compat.c index 6564720f32b7..485db8ee9b28 100644 --- a/net/compat.c +++ b/net/compat.c @@ -297,7 +297,7 @@ void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm) int err = 0, i; for (i = 0; i < fdmax; i++) { - err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags); + err = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags); if (err < 0) break; } diff --git a/net/core/scm.c b/net/core/scm.c index 880027ecf516..eec78e312550 100644 --- a/net/core/scm.c +++ b/net/core/scm.c @@ -319,7 +319,7 @@ void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm) } for (i = 0; i < fdmax; i++) { - err = receive_fd_user(scm->fp->fp[i], cmsg_data + i, o_flags); + err = scm_recv_one_fd(scm->fp->fp[i], cmsg_data + i, o_flags); if (err < 0) break; } From 4e94ddfe2aab72139acb8d5372fac9e6c3f3e383 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Nov 2023 13:49:11 +0100 Subject: [PATCH 7/7] file: remove __receive_fd() Honestly, there's little value in having a helper with and without that int __user *ufd argument. It's just messy and doesn't really give us anything. Just expose receive_fd() with that argument and get rid of that helper. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-5-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner --- drivers/vdpa/vdpa_user/vduse_dev.c | 2 +- fs/file.c | 11 +++-------- include/linux/file.h | 5 +---- include/net/scm.h | 2 +- kernel/pid.c | 2 +- kernel/seccomp.c | 2 +- 6 files changed, 8 insertions(+), 16 deletions(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 0ddd4b8abecb..fafd4610b185 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1157,7 +1157,7 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, fput(f); break; } - ret = receive_fd(f, perm_to_file_flags(entry.perm)); + ret = receive_fd(f, NULL, perm_to_file_flags(entry.perm)); fput(f); break; } diff --git a/fs/file.c b/fs/file.c index c8eaa0b29a08..3b683b9101d8 100644 --- a/fs/file.c +++ b/fs/file.c @@ -1296,7 +1296,7 @@ int replace_fd(unsigned fd, struct file *file, unsigned flags) } /** - * __receive_fd() - Install received file into file descriptor table + * receive_fd() - Install received file into file descriptor table * @file: struct file that was received from another process * @ufd: __user pointer to write new fd number to * @o_flags: the O_* flags to apply to the new fd entry @@ -1310,7 +1310,7 @@ int replace_fd(unsigned fd, struct file *file, unsigned flags) * * Returns newly install fd or -ve on error. */ -int __receive_fd(struct file *file, int __user *ufd, unsigned int o_flags) +int receive_fd(struct file *file, int __user *ufd, unsigned int o_flags) { int new_fd; int error; @@ -1335,6 +1335,7 @@ int __receive_fd(struct file *file, int __user *ufd, unsigned int o_flags) __receive_sock(file); return new_fd; } +EXPORT_SYMBOL_GPL(receive_fd); int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags) { @@ -1350,12 +1351,6 @@ int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags) return new_fd; } -int receive_fd(struct file *file, unsigned int o_flags) -{ - return __receive_fd(file, NULL, o_flags); -} -EXPORT_SYMBOL_GPL(receive_fd); - static int ksys_dup3(unsigned int oldfd, unsigned int newfd, int flags) { int err = -EBADF; diff --git a/include/linux/file.h b/include/linux/file.h index c0d5219c2852..6834a29338c4 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -96,10 +96,7 @@ DEFINE_CLASS(get_unused_fd, int, if (_T >= 0) put_unused_fd(_T), extern void fd_install(unsigned int fd, struct file *file); -extern int __receive_fd(struct file *file, int __user *ufd, - unsigned int o_flags); - -extern int receive_fd(struct file *file, unsigned int o_flags); +int receive_fd(struct file *file, int __user *ufd, unsigned int o_flags); int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags); diff --git a/include/net/scm.h b/include/net/scm.h index 8aae2468bae0..cf68acec4d70 100644 --- a/include/net/scm.h +++ b/include/net/scm.h @@ -214,7 +214,7 @@ static inline int scm_recv_one_fd(struct file *f, int __user *ufd, { if (!ufd) return -EFAULT; - return __receive_fd(f, ufd, flags); + return receive_fd(f, ufd, flags); } #endif /* __LINUX_NET_SCM_H */ diff --git a/kernel/pid.c b/kernel/pid.c index 6500ef956f2f..b52b10865454 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -700,7 +700,7 @@ static int pidfd_getfd(struct pid *pid, int fd) if (IS_ERR(file)) return PTR_ERR(file); - ret = receive_fd(file, O_CLOEXEC); + ret = receive_fd(file, NULL, O_CLOEXEC); fput(file); return ret; diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 255999ba9190..aca7b437882e 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1072,7 +1072,7 @@ static void seccomp_handle_addfd(struct seccomp_kaddfd *addfd, struct seccomp_kn */ list_del_init(&addfd->list); if (!addfd->setfd) - fd = receive_fd(addfd->file, addfd->flags); + fd = receive_fd(addfd->file, NULL, addfd->flags); else fd = receive_fd_replace(addfd->fd, addfd->file, addfd->flags); addfd->ret = fd;