From: Amir Goldstein <amir73il@gmail.com> mainline inclusion from mainline-v6.8-rc1 commit b8e1425bae856b189e2365ff795e30fdd9e77049 category: feature bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBHLU4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- We recently moved fsnotify hook, rw_verify_area() and other checks from do_iter_write() out to its two callers. for consistency, do the same thing for do_iter_read() - move the rw_verify_area() checks and fsnotify hook to the callers vfs_iter_read() and vfs_readv(). This aligns those vfs helpers with the pattern used in vfs_read() and vfs_iocb_iter_read() and the vfs write helpers, where all the checks are in the vfs helpers and the do_* or call_* helpers do the work. This is needed for fanotify "pre content" events. Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231122122715.2561213-13-amir73il@gmail.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- fs/read_write.c | 66 +++++++++++++++++++++++++++++-------------------- 1 file changed, 39 insertions(+), 27 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index dd1457b9209a..a43dd3915c1a 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -775,12 +775,14 @@ static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, return ret; } -static ssize_t do_iter_read(struct file *file, struct iov_iter *iter, - loff_t *pos, rwf_t flags) +ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, + struct iov_iter *iter) { size_t tot_len; ssize_t ret = 0; + if (!file->f_op->read_iter) + return -EINVAL; if (!(file->f_mode & FMODE_READ)) return -EBADF; if (!(file->f_mode & FMODE_CAN_READ)) @@ -789,22 +791,20 @@ static ssize_t do_iter_read(struct file *file, struct iov_iter *iter, tot_len = iov_iter_count(iter); if (!tot_len) goto out; - ret = rw_verify_area(READ, file, pos, tot_len); + ret = rw_verify_area(READ, file, &iocb->ki_pos, tot_len); if (ret < 0) return ret; - if (file->f_op->read_iter) - ret = do_iter_readv_writev(file, iter, pos, READ, flags); - else - ret = do_loop_readv_writev(file, iter, pos, READ, flags); + ret = call_read_iter(file, iocb, iter); out: if (ret >= 0) fsnotify_access(file); return ret; } +EXPORT_SYMBOL(vfs_iocb_iter_read); -ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, - struct iov_iter *iter) +ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos, + rwf_t flags) { size_t tot_len; ssize_t ret = 0; @@ -819,25 +819,16 @@ ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, tot_len = iov_iter_count(iter); if (!tot_len) goto out; - ret = rw_verify_area(READ, file, &iocb->ki_pos, tot_len); + ret = rw_verify_area(READ, file, ppos, tot_len); if (ret < 0) return ret; - ret = call_read_iter(file, iocb, iter); + ret = do_iter_readv_writev(file, iter, ppos, READ, flags); out: if (ret >= 0) fsnotify_access(file); return ret; } -EXPORT_SYMBOL(vfs_iocb_iter_read); - -ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos, - rwf_t flags) -{ - if (!file->f_op->read_iter) - return -EINVAL; - return do_iter_read(file, iter, ppos, flags); -} EXPORT_SYMBOL(vfs_iter_read); ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb, @@ -900,19 +891,40 @@ ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos, EXPORT_SYMBOL(vfs_iter_write); static ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, - unsigned long vlen, loff_t *pos, rwf_t flags) + unsigned long vlen, loff_t *pos, rwf_t flags) { struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; - ssize_t ret; + size_t tot_len; + ssize_t ret = 0; - ret = import_iovec(ITER_DEST, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter); - if (ret >= 0) { - ret = do_iter_read(file, &iter, pos, flags); - kfree(iov); - } + if (!(file->f_mode & FMODE_READ)) + return -EBADF; + if (!(file->f_mode & FMODE_CAN_READ)) + return -EINVAL; + + ret = import_iovec(ITER_DEST, vec, vlen, ARRAY_SIZE(iovstack), &iov, + &iter); + if (ret < 0) + return ret; + + tot_len = iov_iter_count(&iter); + if (!tot_len) + goto out; + + ret = rw_verify_area(READ, file, pos, tot_len); + if (ret < 0) + goto out; + if (file->f_op->read_iter) + ret = do_iter_readv_writev(file, &iter, pos, READ, flags); + else + ret = do_loop_readv_writev(file, &iter, pos, READ, flags); +out: + if (ret >= 0) + fsnotify_access(file); + kfree(iov); return ret; } -- 2.39.2