The patch titled sendfile(): check f_op.splice_write() rather than f_op.sendpage() has been added to the -mm tree. Its filename is sendfile-check-f_opsplice_write-rather-than-f_opsendpage.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: sendfile(): check f_op.splice_write() rather than f_op.sendpage() From: Changli Gao <xiaosuo@xxxxxxxxx> sendfile(2) was reworked with the splice infrastructure, but it still checks f_op.sendpage() instead of f_op.splice_write() wrongly. Although if f_op.sendpage() exists, f_op.splice_write() always exists at the same time currently, the assumption will be broken in future silently. This patch also brings a side effect: sendfile(2) can work with any output file. Some security checks related to f_op are added too. Signed-off-by: Changli Gao <xiaosuo@xxxxxxxxx> Cc: Jens Axboe <jens.axboe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/read_write.c | 2 -- fs/splice.c | 24 +++++++++++++++--------- 2 files changed, 15 insertions(+), 11 deletions(-) diff -puN fs/read_write.c~sendfile-check-f_opsplice_write-rather-than-f_opsendpage fs/read_write.c --- a/fs/read_write.c~sendfile-check-f_opsplice_write-rather-than-f_opsendpage +++ a/fs/read_write.c @@ -826,8 +826,6 @@ static ssize_t do_sendfile(int out_fd, i if (!(out_file->f_mode & FMODE_WRITE)) goto fput_out; retval = -EINVAL; - if (!out_file->f_op || !out_file->f_op->sendpage) - goto fput_out; in_inode = in_file->f_path.dentry->d_inode; out_inode = out_file->f_path.dentry->d_inode; retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); diff -puN fs/splice.c~sendfile-check-f_opsplice_write-rather-than-f_opsendpage fs/splice.c --- a/fs/splice.c~sendfile-check-f_opsplice_write-rather-than-f_opsendpage +++ a/fs/splice.c @@ -648,9 +648,11 @@ static int pipe_to_sendpage(struct pipe_ ret = buf->ops->confirm(pipe, buf); if (!ret) { more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len; - - ret = file->f_op->sendpage(file, buf->page, buf->offset, - sd->len, &pos, more); + if (file->f_op && file->f_op->sendpage) + ret = file->f_op->sendpage(file, buf->page, buf->offset, + sd->len, &pos, more); + else + ret = -EINVAL; } return ret; @@ -1068,8 +1070,9 @@ static long do_splice_from(struct pipe_i if (unlikely(ret < 0)) return ret; - splice_write = out->f_op->splice_write; - if (!splice_write) + if (out->f_op && out->f_op->splice_write) + splice_write = out->f_op->splice_write; + else splice_write = default_file_splice_write; return splice_write(pipe, out, ppos, len, flags); @@ -1093,8 +1096,9 @@ static long do_splice_to(struct file *in if (unlikely(ret < 0)) return ret; - splice_read = in->f_op->splice_read; - if (!splice_read) + if (in->f_op && in->f_op->splice_read) + splice_read = in->f_op->splice_read; + else splice_read = default_file_splice_read; return splice_read(in, ppos, pipe, len, flags); @@ -1316,7 +1320,8 @@ static long do_splice(struct file *in, l if (off_in) return -ESPIPE; if (off_out) { - if (out->f_op->llseek == no_llseek) + if (!out->f_op || !out->f_op->llseek || + out->f_op->llseek == no_llseek) return -EINVAL; if (copy_from_user(&offset, off_out, sizeof(loff_t))) return -EFAULT; @@ -1336,7 +1341,8 @@ static long do_splice(struct file *in, l if (off_out) return -ESPIPE; if (off_in) { - if (in->f_op->llseek == no_llseek) + if (!in->f_op || !in->f_op->llseek || + in->f_op->llseek == no_llseek) return -EINVAL; if (copy_from_user(&offset, off_in, sizeof(loff_t))) return -EFAULT; _ Patches currently in -mm which might be from xiaosuo@xxxxxxxxx are sendfile-check-f_opsplice_write-rather-than-f_opsendpage.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html