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fs/read_write.c
21.8 KB
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/* * linux/fs/read_write.c * * Copyright (C) 1991, 1992 Linus Torvalds */ #include <linux/slab.h> #include <linux/stat.h> #include <linux/fcntl.h> #include <linux/file.h> #include <linux/uio.h> |
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#include <linux/fsnotify.h> |
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#include <linux/security.h> #include <linux/module.h> #include <linux/syscalls.h> |
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#include <linux/pagemap.h> |
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#include <linux/splice.h> |
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#include "read_write.h" |
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#include <asm/uaccess.h> #include <asm/unistd.h> |
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const struct file_operations generic_ro_fops = { |
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.llseek = generic_file_llseek, |
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.read = do_sync_read, .aio_read = generic_file_aio_read, |
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.mmap = generic_file_readonly_mmap, |
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.splice_read = generic_file_splice_read, |
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}; EXPORT_SYMBOL(generic_ro_fops); |
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static inline int unsigned_offsets(struct file *file) |
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{ |
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return file->f_mode & FMODE_UNSIGNED_OFFSET; |
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} |
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/** * generic_file_llseek_unlocked - lockless generic llseek implementation * @file: file structure to seek on * @offset: file offset to seek to * @origin: type of seek * * Updates the file offset to the value specified by @offset and @origin. * Locking must be provided by the caller. */ |
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loff_t generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) |
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{ |
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struct inode *inode = file->f_mapping->host; |
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switch (origin) { |
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case SEEK_END: offset += inode->i_size; break; case SEEK_CUR: |
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/* * Here we special-case the lseek(fd, 0, SEEK_CUR) * position-querying operation. Avoid rewriting the "same" * f_pos value back to the file because a concurrent read(), * write() or lseek() might have altered it */ if (offset == 0) return file->f_pos; |
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offset += file->f_pos; break; |
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case SEEK_DATA: /* * In the generic case the entire file is data, so as long as * offset isn't at the end of the file then the offset is data. */ if (offset >= inode->i_size) return -ENXIO; break; case SEEK_HOLE: /* * There is a virtual hole at the end of the file, so as long as * offset isn't i_size or larger, return i_size. */ if (offset >= inode->i_size) return -ENXIO; offset = inode->i_size; break; |
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} |
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|
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if (offset < 0 && !unsigned_offsets(file)) |
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return -EINVAL; if (offset > inode->i_sb->s_maxbytes) |
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return -EINVAL; /* Special lock needed here? */ if (offset != file->f_pos) { file->f_pos = offset; file->f_version = 0; |
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} |
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return offset; |
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} |
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EXPORT_SYMBOL(generic_file_llseek_unlocked); |
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|
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/** * generic_file_llseek - generic llseek implementation for regular files * @file: file structure to seek on * @offset: file offset to seek to * @origin: type of seek * * This is a generic implemenation of ->llseek useable for all normal local * filesystems. It just updates the file offset to the value specified by * @offset and @origin under i_mutex. */ |
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loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) |
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{ |
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loff_t rval; |
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mutex_lock(&file->f_dentry->d_inode->i_mutex); |
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rval = generic_file_llseek_unlocked(file, offset, origin); |
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mutex_unlock(&file->f_dentry->d_inode->i_mutex); |
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return rval; |
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} |
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EXPORT_SYMBOL(generic_file_llseek); |
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|
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/** * noop_llseek - No Operation Performed llseek implementation * @file: file structure to seek on * @offset: file offset to seek to * @origin: type of seek * * This is an implementation of ->llseek useable for the rare special case when * userspace expects the seek to succeed but the (device) file is actually not * able to perform the seek. In this case you use noop_llseek() instead of * falling back to the default implementation of ->llseek. */ loff_t noop_llseek(struct file *file, loff_t offset, int origin) { return file->f_pos; } EXPORT_SYMBOL(noop_llseek); |
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loff_t no_llseek(struct file *file, loff_t offset, int origin) { return -ESPIPE; } EXPORT_SYMBOL(no_llseek); loff_t default_llseek(struct file *file, loff_t offset, int origin) { |
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struct inode *inode = file->f_path.dentry->d_inode; |
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loff_t retval; |
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|
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mutex_lock(&inode->i_mutex); |
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switch (origin) { |
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case SEEK_END: |
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offset += i_size_read(inode); |
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break; |
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case SEEK_CUR: |
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if (offset == 0) { retval = file->f_pos; goto out; } |
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offset += file->f_pos; |
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break; case SEEK_DATA: /* * In the generic case the entire file is data, so as * long as offset isn't at the end of the file then the * offset is data. */ |
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if (offset >= inode->i_size) { retval = -ENXIO; goto out; } |
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break; case SEEK_HOLE: /* * There is a virtual hole at the end of the file, so * as long as offset isn't i_size or larger, return * i_size. */ |
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if (offset >= inode->i_size) { retval = -ENXIO; goto out; } |
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offset = inode->i_size; break; |
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} retval = -EINVAL; |
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if (offset >= 0 || unsigned_offsets(file)) { |
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if (offset != file->f_pos) { file->f_pos = offset; file->f_version = 0; } retval = offset; } |
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out: |
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mutex_unlock(&inode->i_mutex); |
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return retval; } EXPORT_SYMBOL(default_llseek); loff_t vfs_llseek(struct file *file, loff_t offset, int origin) { loff_t (*fn)(struct file *, loff_t, int); fn = no_llseek; if (file->f_mode & FMODE_LSEEK) { |
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if (file->f_op && file->f_op->llseek) fn = file->f_op->llseek; } return fn(file, offset, origin); } EXPORT_SYMBOL(vfs_llseek); |
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SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, origin) |
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{ off_t retval; struct file * file; int fput_needed; retval = -EBADF; file = fget_light(fd, &fput_needed); if (!file) goto bad; retval = -EINVAL; |
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if (origin <= SEEK_MAX) { |
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loff_t res = vfs_llseek(file, offset, origin); retval = res; if (res != (loff_t)retval) retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ } fput_light(file, fput_needed); bad: return retval; } #ifdef __ARCH_WANT_SYS_LLSEEK |
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SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, unsigned long, offset_low, loff_t __user *, result, unsigned int, origin) |
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{ int retval; struct file * file; loff_t offset; int fput_needed; retval = -EBADF; file = fget_light(fd, &fput_needed); if (!file) goto bad; retval = -EINVAL; |
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if (origin > SEEK_MAX) |
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goto out_putf; offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, origin); retval = (int)offset; if (offset >= 0) { retval = -EFAULT; if (!copy_to_user(result, &offset, sizeof(offset))) retval = 0; } out_putf: fput_light(file, fput_needed); bad: return retval; } #endif |
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|
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/* * rw_verify_area doesn't like huge counts. We limit * them to something that fits in "int" so that others * won't have to do range checks all the time. */ |
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int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) { struct inode *inode; loff_t pos; |
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int retval = -EINVAL; |
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|
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inode = file->f_path.dentry->d_inode; |
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if (unlikely((ssize_t) count < 0)) |
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return retval; |
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pos = *ppos; |
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if (unlikely(pos < 0)) { if (!unsigned_offsets(file)) return retval; if (count >= -pos) /* both values are in 0..LLONG_MAX */ return -EOVERFLOW; } else if (unlikely((loff_t) (pos + count) < 0)) { if (!unsigned_offsets(file)) |
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return retval; } |
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if (unlikely(inode->i_flock && mandatory_lock(inode))) { |
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retval = locks_mandatory_area( |
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read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, inode, file, pos, count); if (retval < 0) return retval; } |
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retval = security_file_permission(file, read_write == READ ? MAY_READ : MAY_WRITE); if (retval) return retval; |
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return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
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} |
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static void wait_on_retry_sync_kiocb(struct kiocb *iocb) { set_current_state(TASK_UNINTERRUPTIBLE); if (!kiocbIsKicked(iocb)) schedule(); else kiocbClearKicked(iocb); __set_current_state(TASK_RUNNING); } |
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ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) { |
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struct iovec iov = { .iov_base = buf, .iov_len = len }; |
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struct kiocb kiocb; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; |
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kiocb.ki_left = len; |
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kiocb.ki_nbytes = len; |
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for (;;) { ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); if (ret != -EIOCBRETRY) break; |
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wait_on_retry_sync_kiocb(&kiocb); |
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} |
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|
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if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; return ret; } EXPORT_SYMBOL(do_sync_read); ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) { ssize_t ret; if (!(file->f_mode & FMODE_READ)) return -EBADF; if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) return -EINVAL; if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) return -EFAULT; ret = rw_verify_area(READ, file, pos, count); |
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if (ret >= 0) { count = ret; |
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if (file->f_op->read) ret = file->f_op->read(file, buf, count, pos); else ret = do_sync_read(file, buf, count, pos); if (ret > 0) { |
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fsnotify_access(file); |
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add_rchar(current, ret); |
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} |
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inc_syscr(current); |
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} return ret; } EXPORT_SYMBOL(vfs_read); ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) { |
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struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
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struct kiocb kiocb; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; |
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kiocb.ki_left = len; |
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kiocb.ki_nbytes = len; |
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for (;;) { ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); if (ret != -EIOCBRETRY) break; |
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wait_on_retry_sync_kiocb(&kiocb); |
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} |
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|
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if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; return ret; } EXPORT_SYMBOL(do_sync_write); ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) { ssize_t ret; if (!(file->f_mode & FMODE_WRITE)) return -EBADF; if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) return -EINVAL; if (unlikely(!access_ok(VERIFY_READ, buf, count))) return -EFAULT; ret = rw_verify_area(WRITE, file, pos, count); |
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if (ret >= 0) { count = ret; |
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if (file->f_op->write) ret = file->f_op->write(file, buf, count, pos); else ret = do_sync_write(file, buf, count, pos); if (ret > 0) { |
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fsnotify_modify(file); |
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add_wchar(current, ret); |
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} |
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inc_syscw(current); |
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} return ret; } EXPORT_SYMBOL(vfs_write); static inline loff_t file_pos_read(struct file *file) { return file->f_pos; } static inline void file_pos_write(struct file *file, loff_t pos) { file->f_pos = pos; } |
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SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
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{ struct file *file; ssize_t ret = -EBADF; int fput_needed; file = fget_light(fd, &fput_needed); if (file) { loff_t pos = file_pos_read(file); ret = vfs_read(file, buf, count, &pos); file_pos_write(file, pos); fput_light(file, fput_needed); } return ret; } |
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SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, size_t, count) |
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{ struct file *file; ssize_t ret = -EBADF; int fput_needed; file = fget_light(fd, &fput_needed); if (file) { loff_t pos = file_pos_read(file); ret = vfs_write(file, buf, count, &pos); file_pos_write(file, pos); fput_light(file, fput_needed); } return ret; } |
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SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf, size_t count, loff_t pos) |
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{ struct file *file; ssize_t ret = -EBADF; int fput_needed; if (pos < 0) return -EINVAL; file = fget_light(fd, &fput_needed); if (file) { ret = -ESPIPE; if (file->f_mode & FMODE_PREAD) ret = vfs_read(file, buf, count, &pos); fput_light(file, fput_needed); } return ret; } |
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#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos) { return SYSC_pread64((unsigned int) fd, (char __user *) buf, (size_t) count, pos); } SYSCALL_ALIAS(sys_pread64, SyS_pread64); #endif |
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SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf, size_t count, loff_t pos) |
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{ struct file *file; ssize_t ret = -EBADF; int fput_needed; if (pos < 0) return -EINVAL; file = fget_light(fd, &fput_needed); if (file) { ret = -ESPIPE; if (file->f_mode & FMODE_PWRITE) ret = vfs_write(file, buf, count, &pos); fput_light(file, fput_needed); } return ret; } |
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#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos) { return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf, (size_t) count, pos); } SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64); #endif |
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/* * Reduce an iovec's length in-place. Return the resulting number of segments */ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) { unsigned long seg = 0; size_t len = 0; while (seg < nr_segs) { seg++; if (len + iov->iov_len >= to) { iov->iov_len = to - len; break; } len += iov->iov_len; iov++; } return seg; } |
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544 |
EXPORT_SYMBOL(iov_shorten); |
1da177e4c Linux-2.6.12-rc2 |
545 |
|
ee0b3e671 [PATCH] Remove re... |
546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 |
ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) { struct kiocb kiocb; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; kiocb.ki_left = len; kiocb.ki_nbytes = len; for (;;) { ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); if (ret != -EIOCBRETRY) break; wait_on_retry_sync_kiocb(&kiocb); } if (ret == -EIOCBQUEUED) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; return ret; } /* Do it by hand, with file-ops */ ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, unsigned long nr_segs, loff_t *ppos, io_fn_t fn) { struct iovec *vector = iov; ssize_t ret = 0; while (nr_segs > 0) { void __user *base; size_t len; ssize_t nr; base = vector->iov_base; len = vector->iov_len; vector++; nr_segs--; nr = fn(filp, base, len, ppos); if (nr < 0) { if (!ret) ret = nr; break; } ret += nr; if (nr != len) break; } return ret; } |
1da177e4c Linux-2.6.12-rc2 |
601 602 |
/* A write operation does a read from user space and vice versa */ #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) |
eed4e51fb [PATCH] Add vecto... |
603 604 605 606 |
ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, unsigned long nr_segs, unsigned long fast_segs, struct iovec *fast_pointer, struct iovec **ret_pointer) |
435f49a51 readv/writev: do ... |
607 |
{ |
eed4e51fb [PATCH] Add vecto... |
608 |
unsigned long seg; |
435f49a51 readv/writev: do ... |
609 |
ssize_t ret; |
eed4e51fb [PATCH] Add vecto... |
610 |
struct iovec *iov = fast_pointer; |
435f49a51 readv/writev: do ... |
611 612 613 614 615 |
/* * SuS says "The readv() function *may* fail if the iovcnt argument * was less than or equal to 0, or greater than {IOV_MAX}. Linux has * traditionally returned zero for zero segments, so... */ |
eed4e51fb [PATCH] Add vecto... |
616 617 |
if (nr_segs == 0) { ret = 0; |
435f49a51 readv/writev: do ... |
618 |
goto out; |
eed4e51fb [PATCH] Add vecto... |
619 |
} |
435f49a51 readv/writev: do ... |
620 621 622 623 |
/* * First get the "struct iovec" from user memory and * verify all the pointers */ |
eed4e51fb [PATCH] Add vecto... |
624 625 |
if (nr_segs > UIO_MAXIOV) { ret = -EINVAL; |
435f49a51 readv/writev: do ... |
626 |
goto out; |
eed4e51fb [PATCH] Add vecto... |
627 628 |
} if (nr_segs > fast_segs) { |
435f49a51 readv/writev: do ... |
629 |
iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
eed4e51fb [PATCH] Add vecto... |
630 631 |
if (iov == NULL) { ret = -ENOMEM; |
435f49a51 readv/writev: do ... |
632 |
goto out; |
eed4e51fb [PATCH] Add vecto... |
633 |
} |
435f49a51 readv/writev: do ... |
634 |
} |
eed4e51fb [PATCH] Add vecto... |
635 636 |
if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { ret = -EFAULT; |
435f49a51 readv/writev: do ... |
637 |
goto out; |
eed4e51fb [PATCH] Add vecto... |
638 |
} |
435f49a51 readv/writev: do ... |
639 |
/* |
eed4e51fb [PATCH] Add vecto... |
640 641 642 643 |
* According to the Single Unix Specification we should return EINVAL * if an element length is < 0 when cast to ssize_t or if the * total length would overflow the ssize_t return value of the * system call. |
435f49a51 readv/writev: do ... |
644 645 646 647 |
* * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the * overflow case. */ |
eed4e51fb [PATCH] Add vecto... |
648 |
ret = 0; |
435f49a51 readv/writev: do ... |
649 650 651 |
for (seg = 0; seg < nr_segs; seg++) { void __user *buf = iov[seg].iov_base; ssize_t len = (ssize_t)iov[seg].iov_len; |
eed4e51fb [PATCH] Add vecto... |
652 653 654 |
/* see if we we're about to use an invalid len or if * it's about to overflow ssize_t */ |
435f49a51 readv/writev: do ... |
655 |
if (len < 0) { |
eed4e51fb [PATCH] Add vecto... |
656 |
ret = -EINVAL; |
435f49a51 readv/writev: do ... |
657 |
goto out; |
eed4e51fb [PATCH] Add vecto... |
658 659 660 |
} if (unlikely(!access_ok(vrfy_dir(type), buf, len))) { ret = -EFAULT; |
435f49a51 readv/writev: do ... |
661 662 663 664 665 |
goto out; } if (len > MAX_RW_COUNT - ret) { len = MAX_RW_COUNT - ret; iov[seg].iov_len = len; |
eed4e51fb [PATCH] Add vecto... |
666 |
} |
eed4e51fb [PATCH] Add vecto... |
667 |
ret += len; |
435f49a51 readv/writev: do ... |
668 |
} |
eed4e51fb [PATCH] Add vecto... |
669 670 671 672 |
out: *ret_pointer = iov; return ret; } |
1da177e4c Linux-2.6.12-rc2 |
673 674 675 676 |
static ssize_t do_readv_writev(int type, struct file *file, const struct iovec __user * uvector, unsigned long nr_segs, loff_t *pos) { |
1da177e4c Linux-2.6.12-rc2 |
677 678 |
size_t tot_len; struct iovec iovstack[UIO_FASTIOV]; |
ee0b3e671 [PATCH] Remove re... |
679 |
struct iovec *iov = iovstack; |
1da177e4c Linux-2.6.12-rc2 |
680 |
ssize_t ret; |
1da177e4c Linux-2.6.12-rc2 |
681 682 |
io_fn_t fn; iov_fn_t fnv; |
eed4e51fb [PATCH] Add vecto... |
683 684 |
if (!file->f_op) { ret = -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
685 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
686 |
} |
1da177e4c Linux-2.6.12-rc2 |
687 |
|
eed4e51fb [PATCH] Add vecto... |
688 689 690 |
ret = rw_copy_check_uvector(type, uvector, nr_segs, ARRAY_SIZE(iovstack), iovstack, &iov); if (ret <= 0) |
1da177e4c Linux-2.6.12-rc2 |
691 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
692 |
|
eed4e51fb [PATCH] Add vecto... |
693 |
tot_len = ret; |
1da177e4c Linux-2.6.12-rc2 |
694 |
ret = rw_verify_area(type, file, pos, tot_len); |
e28cc7157 Relax the rw_veri... |
695 |
if (ret < 0) |
1da177e4c Linux-2.6.12-rc2 |
696 697 698 699 700 |
goto out; fnv = NULL; if (type == READ) { fn = file->f_op->read; |
ee0b3e671 [PATCH] Remove re... |
701 |
fnv = file->f_op->aio_read; |
1da177e4c Linux-2.6.12-rc2 |
702 703 |
} else { fn = (io_fn_t)file->f_op->write; |
ee0b3e671 [PATCH] Remove re... |
704 |
fnv = file->f_op->aio_write; |
1da177e4c Linux-2.6.12-rc2 |
705 |
} |
ee0b3e671 [PATCH] Remove re... |
706 707 708 709 710 |
if (fnv) ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, pos, fnv); else ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); |
1da177e4c Linux-2.6.12-rc2 |
711 |
|
1da177e4c Linux-2.6.12-rc2 |
712 713 714 |
out: if (iov != iovstack) kfree(iov); |
0eeca2830 [PATCH] inotify |
715 716 |
if ((ret + (type == READ)) > 0) { if (type == READ) |
2a12a9d78 fsnotify: pass a ... |
717 |
fsnotify_access(file); |
0eeca2830 [PATCH] inotify |
718 |
else |
2a12a9d78 fsnotify: pass a ... |
719 |
fsnotify_modify(file); |
0eeca2830 [PATCH] inotify |
720 |
} |
1da177e4c Linux-2.6.12-rc2 |
721 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
722 723 724 725 726 727 728 |
} ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, unsigned long vlen, loff_t *pos) { if (!(file->f_mode & FMODE_READ)) return -EBADF; |
ee0b3e671 [PATCH] Remove re... |
729 |
if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) |
1da177e4c Linux-2.6.12-rc2 |
730 731 732 733 734 735 736 737 738 739 740 741 |
return -EINVAL; return do_readv_writev(READ, file, vec, vlen, pos); } EXPORT_SYMBOL(vfs_readv); ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, unsigned long vlen, loff_t *pos) { if (!(file->f_mode & FMODE_WRITE)) return -EBADF; |
ee0b3e671 [PATCH] Remove re... |
742 |
if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) |
1da177e4c Linux-2.6.12-rc2 |
743 744 745 746 747 748 |
return -EINVAL; return do_readv_writev(WRITE, file, vec, vlen, pos); } EXPORT_SYMBOL(vfs_writev); |
3cdad4288 [CVE-2009-0029] S... |
749 750 |
SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, unsigned long, vlen) |
1da177e4c Linux-2.6.12-rc2 |
751 752 753 754 755 756 757 758 759 760 761 762 763 764 |
{ struct file *file; ssize_t ret = -EBADF; int fput_needed; file = fget_light(fd, &fput_needed); if (file) { loff_t pos = file_pos_read(file); ret = vfs_readv(file, vec, vlen, &pos); file_pos_write(file, pos); fput_light(file, fput_needed); } if (ret > 0) |
4b98d11b4 [PATCH] ifdef ->r... |
765 766 |
add_rchar(current, ret); inc_syscr(current); |
1da177e4c Linux-2.6.12-rc2 |
767 768 |
return ret; } |
3cdad4288 [CVE-2009-0029] S... |
769 770 |
SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, unsigned long, vlen) |
1da177e4c Linux-2.6.12-rc2 |
771 772 773 774 775 776 777 778 779 780 781 782 783 784 |
{ struct file *file; ssize_t ret = -EBADF; int fput_needed; file = fget_light(fd, &fput_needed); if (file) { loff_t pos = file_pos_read(file); ret = vfs_writev(file, vec, vlen, &pos); file_pos_write(file, pos); fput_light(file, fput_needed); } if (ret > 0) |
4b98d11b4 [PATCH] ifdef ->r... |
785 786 |
add_wchar(current, ret); inc_syscw(current); |
1da177e4c Linux-2.6.12-rc2 |
787 788 |
return ret; } |
601cc11d0 Make non-compat p... |
789 790 791 792 793 |
static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) { #define HALF_LONG_BITS (BITS_PER_LONG / 2) return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; } |
f3554f4bc preadv/pwritev: A... |
794 |
SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, |
601cc11d0 Make non-compat p... |
795 |
unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4bc preadv/pwritev: A... |
796 |
{ |
601cc11d0 Make non-compat p... |
797 |
loff_t pos = pos_from_hilo(pos_h, pos_l); |
f3554f4bc preadv/pwritev: A... |
798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 |
struct file *file; ssize_t ret = -EBADF; int fput_needed; if (pos < 0) return -EINVAL; file = fget_light(fd, &fput_needed); if (file) { ret = -ESPIPE; if (file->f_mode & FMODE_PREAD) ret = vfs_readv(file, vec, vlen, &pos); fput_light(file, fput_needed); } if (ret > 0) add_rchar(current, ret); inc_syscr(current); return ret; } SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, |
601cc11d0 Make non-compat p... |
820 |
unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4bc preadv/pwritev: A... |
821 |
{ |
601cc11d0 Make non-compat p... |
822 |
loff_t pos = pos_from_hilo(pos_h, pos_l); |
f3554f4bc preadv/pwritev: A... |
823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 |
struct file *file; ssize_t ret = -EBADF; int fput_needed; if (pos < 0) return -EINVAL; file = fget_light(fd, &fput_needed); if (file) { ret = -ESPIPE; if (file->f_mode & FMODE_PWRITE) ret = vfs_writev(file, vec, vlen, &pos); fput_light(file, fput_needed); } if (ret > 0) add_wchar(current, ret); inc_syscw(current); return ret; } |
1da177e4c Linux-2.6.12-rc2 |
843 844 845 846 847 848 849 |
static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, size_t count, loff_t max) { struct file * in_file, * out_file; struct inode * in_inode, * out_inode; loff_t pos; ssize_t retval; |
534f2aaa6 sys_sendfile: swi... |
850 |
int fput_needed_in, fput_needed_out, fl; |
1da177e4c Linux-2.6.12-rc2 |
851 852 853 854 855 856 857 858 859 860 |
/* * Get input file, and verify that it is ok.. */ retval = -EBADF; in_file = fget_light(in_fd, &fput_needed_in); if (!in_file) goto out; if (!(in_file->f_mode & FMODE_READ)) goto fput_in; |
1da177e4c Linux-2.6.12-rc2 |
861 862 863 864 865 866 867 |
retval = -ESPIPE; if (!ppos) ppos = &in_file->f_pos; else if (!(in_file->f_mode & FMODE_PREAD)) goto fput_in; retval = rw_verify_area(READ, in_file, ppos, count); |
e28cc7157 Relax the rw_veri... |
868 |
if (retval < 0) |
1da177e4c Linux-2.6.12-rc2 |
869 |
goto fput_in; |
e28cc7157 Relax the rw_veri... |
870 |
count = retval; |
1da177e4c Linux-2.6.12-rc2 |
871 |
|
1da177e4c Linux-2.6.12-rc2 |
872 873 874 875 876 877 878 879 880 881 |
/* * Get output file, and verify that it is ok.. */ retval = -EBADF; out_file = fget_light(out_fd, &fput_needed_out); if (!out_file) goto fput_in; if (!(out_file->f_mode & FMODE_WRITE)) goto fput_out; retval = -EINVAL; |
6818173bd splice: implement... |
882 |
in_inode = in_file->f_path.dentry->d_inode; |
0f7fc9e4d [PATCH] VFS: chan... |
883 |
out_inode = out_file->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
884 |
retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); |
e28cc7157 Relax the rw_veri... |
885 |
if (retval < 0) |
1da177e4c Linux-2.6.12-rc2 |
886 |
goto fput_out; |
e28cc7157 Relax the rw_veri... |
887 |
count = retval; |
1da177e4c Linux-2.6.12-rc2 |
888 |
|
1da177e4c Linux-2.6.12-rc2 |
889 890 891 892 |
if (!max) max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); pos = *ppos; |
1da177e4c Linux-2.6.12-rc2 |
893 894 895 896 897 898 |
if (unlikely(pos + count > max)) { retval = -EOVERFLOW; if (pos >= max) goto fput_out; count = max - pos; } |
d96e6e716 Remove remnants o... |
899 |
fl = 0; |
534f2aaa6 sys_sendfile: swi... |
900 |
#if 0 |
d96e6e716 Remove remnants o... |
901 902 903 904 905 906 907 908 |
/* * We need to debate whether we can enable this or not. The * man page documents EAGAIN return for the output at least, * and the application is arguably buggy if it doesn't expect * EAGAIN on a non-blocking file descriptor. */ if (in_file->f_flags & O_NONBLOCK) fl = SPLICE_F_NONBLOCK; |
534f2aaa6 sys_sendfile: swi... |
909 |
#endif |
d96e6e716 Remove remnants o... |
910 |
retval = do_splice_direct(in_file, ppos, out_file, count, fl); |
1da177e4c Linux-2.6.12-rc2 |
911 912 |
if (retval > 0) { |
4b98d11b4 [PATCH] ifdef ->r... |
913 914 |
add_rchar(current, retval); add_wchar(current, retval); |
1da177e4c Linux-2.6.12-rc2 |
915 |
} |
1da177e4c Linux-2.6.12-rc2 |
916 |
|
4b98d11b4 [PATCH] ifdef ->r... |
917 918 |
inc_syscr(current); inc_syscw(current); |
1da177e4c Linux-2.6.12-rc2 |
919 920 921 922 923 924 925 926 927 928 |
if (*ppos > max) retval = -EOVERFLOW; fput_out: fput_light(out_file, fput_needed_out); fput_in: fput_light(in_file, fput_needed_in); out: return retval; } |
002c8976e [CVE-2009-0029] S... |
929 |
SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
1da177e4c Linux-2.6.12-rc2 |
930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 |
{ loff_t pos; off_t off; ssize_t ret; if (offset) { if (unlikely(get_user(off, offset))) return -EFAULT; pos = off; ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); if (unlikely(put_user(pos, offset))) return -EFAULT; return ret; } return do_sendfile(out_fd, in_fd, NULL, count, 0); } |
002c8976e [CVE-2009-0029] S... |
947 |
SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
1da177e4c Linux-2.6.12-rc2 |
948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 |
{ loff_t pos; ssize_t ret; if (offset) { if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) return -EFAULT; ret = do_sendfile(out_fd, in_fd, &pos, count, 0); if (unlikely(put_user(pos, offset))) return -EFAULT; return ret; } return do_sendfile(out_fd, in_fd, NULL, count, 0); } |