From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: [RFC][PATCH 10/13] make dump_emit() use vfs_write() instead of banging at ->f_op->write directly Date: Wed, 09 Oct 2013 01:15:47 +0100 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: torvalds@linux-foundation.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org ... and deal with short writes properly - the output might be to pipe, after all; as it is, e.g. no-MMU case of elf_fdpic coredump can write a whole lot more than a page worth of data at one call. Signed-off-by: Al Viro --- fs/coredump.c | 17 ++++++++++++----- 1 files changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/coredump.c b/fs/coredump.c index 319f973..478ebad 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -696,13 +696,20 @@ EXPORT_SYMBOL(dump_write); int dump_emit(struct coredump_params *cprm, const void *addr, int nr) { struct file *file = cprm->file; - if (dump_interrupted() || !access_ok(VERIFY_READ, addr, nr)) - return 0; + loff_t pos = file->f_pos; + ssize_t n; if (cprm->written + nr > cprm->limit) return 0; - if (file->f_op->write(file, addr, nr, &file->f_pos) != nr) - return 0; - cprm->written += nr; + while (nr) { + if (dump_interrupted()) + return 0; + n = vfs_write(file, addr, nr, &pos); + if (n < 0) + return 0; + file->f_pos = pos; + cprm->written += n; + nr -= n; + } return 1; } EXPORT_SYMBOL(dump_emit); -- 1.7.2.5