5.10-stable review patch. If anyone has any objections, please let me know.
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From: Eric W. Biederman ebiederm@xmission.com
[ Upstream commit 8760c909f54a82aaa6e76da19afe798a0c77c3c3 ]
The function __close_fd was added to support binder[1]. Now that binder has been fixed to no longer need __close_fd[2] all calls to __close_fd pass current->files.
Therefore transform the files parameter into a local variable initialized to current->files, and rename __close_fd to close_fd to reflect this change, and keep it in sync with the similar changes to __alloc_fd, and __fd_install.
This removes the need for callers to care about the extra care that needs to be take if anything except current->files is passed, by limiting the callers to only operation on current->files.
[1] 483ce1d4b8c3 ("take descriptor-related part of close() to file.c") [2] 44d8047f1d87 ("binder: use standard functions to allocate fds") Acked-by: Christian Brauner christian.brauner@ubuntu.com v1: https://lkml.kernel.org/r/20200817220425.9389-17-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20201120231441.29911-21-ebiederm@xmission.com Signed-off-by: Eric W. Biederman ebiederm@xmission.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/file.c | 10 ++++------ fs/open.c | 2 +- include/linux/fdtable.h | 3 +-- include/linux/syscalls.h | 6 +++--- 4 files changed, 9 insertions(+), 12 deletions(-)
diff --git a/fs/file.c b/fs/file.c index 48d0306e42ccc..fdb84a64724b7 100644 --- a/fs/file.c +++ b/fs/file.c @@ -659,11 +659,9 @@ static struct file *pick_file(struct files_struct *files, unsigned fd) return file; }
-/* - * The same warnings as for __alloc_fd()/__fd_install() apply here... - */ -int __close_fd(struct files_struct *files, unsigned fd) +int close_fd(unsigned fd) { + struct files_struct *files = current->files; struct file *file;
file = pick_file(files, fd); @@ -672,7 +670,7 @@ int __close_fd(struct files_struct *files, unsigned fd)
return filp_close(file, files); } -EXPORT_SYMBOL(__close_fd); /* for ksys_close() */ +EXPORT_SYMBOL(close_fd); /* for ksys_close() */
/** * __close_range() - Close all file descriptors in a given range. @@ -1087,7 +1085,7 @@ int replace_fd(unsigned fd, struct file *file, unsigned flags) struct files_struct *files = current->files;
if (!file) - return __close_fd(files, fd); + return close_fd(fd);
if (fd >= rlimit(RLIMIT_NOFILE)) return -EBADF; diff --git a/fs/open.c b/fs/open.c index 83f62cf1432c8..48933cbb75391 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1310,7 +1310,7 @@ EXPORT_SYMBOL(filp_close); */ SYSCALL_DEFINE1(close, unsigned int, fd) { - int retval = __close_fd(current->files, fd); + int retval = close_fd(fd);
/* can't restart close syscall because file table entry was cleared */ if (unlikely(retval == -ERESTARTSYS || diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index d26b884fcc5cc..4ed3589f9294e 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -124,8 +124,7 @@ int iterate_fd(struct files_struct *, unsigned, int (*)(const void *, struct file *, unsigned), const void *);
-extern int __close_fd(struct files_struct *files, - unsigned int fd); +extern int close_fd(unsigned int fd); extern int __close_range(unsigned int fd, unsigned int max_fd, unsigned int flags); extern int close_fd_get_file(unsigned int fd, struct file **res); extern int unshare_fd(unsigned long unshare_flags, unsigned int max_fds, diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 17a24e1180dad..0bc3dd86f9e50 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1320,16 +1320,16 @@ static inline long ksys_ftruncate(unsigned int fd, loff_t length) return do_sys_ftruncate(fd, length, 1); }
-extern int __close_fd(struct files_struct *files, unsigned int fd); +extern int close_fd(unsigned int fd);
/* * In contrast to sys_close(), this stub does not check whether the syscall * should or should not be restarted, but returns the raw error codes from - * __close_fd(). + * close_fd(). */ static inline int ksys_close(unsigned int fd) { - return __close_fd(current->files, fd); + return close_fd(fd); }
extern long do_sys_truncate(const char __user *pathname, loff_t length);