From: Vivek Goyal <vgoyal@redhat.com>
To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
kvm@vger.kernel.org, linux-nvdimm@lists.01.org
Cc: vgoyal@redhat.com, miklos@szeredi.hu, stefanha@redhat.com,
dgilbert@redhat.com, swhiteho@redhat.com
Subject: [PATCH v2 02/30] fuse: Clear setuid bit even in cache=never path
Date: Wed, 15 May 2019 15:26:47 -0400 [thread overview]
Message-ID: <20190515192715.18000-3-vgoyal@redhat.com> (raw)
In-Reply-To: <20190515192715.18000-1-vgoyal@redhat.com>
If fuse daemon is started with cache=never, fuse falls back to direct IO.
In that write path we don't call file_remove_privs() and that means setuid
bit is not cleared if unpriviliged user writes to a file with setuid bit set.
pjdfstest chmod test 12.t tests this and fails.
Fix this by calling fuse_remove_privs() even for direct I/O path.
I tested this as follows.
- Run fuse example pasthrough fs.
$ passthrough_ll /mnt/pasthrough-mnt -o default_permissions,allow_other,cache=never
$ mkdir /mnt/pasthrough-mnt/testdir
$ cd /mnt/pasthrough-mnt/testdir
$ prove -rv pjdfstests/tests/chmod/12.t
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
fs/fuse/file.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 06096b60f1df..5baf07fd2876 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1456,14 +1456,18 @@ static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from)
/* Don't allow parallel writes to the same file */
inode_lock(inode);
res = generic_write_checks(iocb, from);
- if (res > 0) {
- if (!is_sync_kiocb(iocb) && iocb->ki_flags & IOCB_DIRECT) {
- res = fuse_direct_IO(iocb, from);
- } else {
- res = fuse_direct_io(&io, from, &iocb->ki_pos,
- FUSE_DIO_WRITE);
- }
+ if (res <= 0)
+ goto out;
+
+ res = file_remove_privs(iocb->ki_filp);
+ if (res)
+ goto out;
+ if (!is_sync_kiocb(iocb) && iocb->ki_flags & IOCB_DIRECT) {
+ res = fuse_direct_IO(iocb, from);
+ } else {
+ res = fuse_direct_io(&io, from, &iocb->ki_pos, FUSE_DIO_WRITE);
}
+out:
fuse_invalidate_attr(inode);
if (res > 0)
fuse_write_update_size(inode, iocb->ki_pos);
--
2.20.1
next prev parent reply other threads:[~2019-05-15 19:29 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-15 19:26 [PATCH v2 00/30] [RFC] virtio-fs: shared file system for virtual machines Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 01/30] fuse: delete dentry if timeout is zero Vivek Goyal
2019-05-15 19:26 ` Vivek Goyal [this message]
2019-05-20 14:41 ` [PATCH v2 02/30] fuse: Clear setuid bit even in cache=never path Miklos Szeredi
2019-05-20 14:44 ` Miklos Szeredi
2019-05-20 20:25 ` Nikolaus Rath
2019-05-21 15:01 ` Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 03/30] fuse: Use default_file_splice_read for direct IO Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 04/30] fuse: export fuse_end_request() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 05/30] fuse: export fuse_len_args() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 06/30] fuse: Export fuse_send_init_request() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 07/30] fuse: export fuse_get_unique() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 08/30] fuse: extract fuse_fill_super_common() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 09/30] fuse: add fuse_iqueue_ops callbacks Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 10/30] fuse: Separate fuse device allocation and installation in fuse_conn Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 11/30] virtio_fs: add skeleton virtio_fs.ko module Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 12/30] dax: remove block device dependencies Vivek Goyal
2019-05-16 0:21 ` Dan Williams
2019-05-16 10:07 ` Stefan Hajnoczi
2019-05-16 14:23 ` Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 13/30] dax: Pass dax_dev to dax_writeback_mapping_range() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 14/30] virtio: Add get_shm_region method Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 15/30] virtio: Implement get_shm_region for PCI transport Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 16/30] virtio: Implement get_shm_region for MMIO transport Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 17/30] fuse, dax: add fuse_conn->dax_dev field Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 18/30] virtio_fs, dax: Set up virtio_fs dax_device Vivek Goyal
2019-07-17 17:27 ` Halil Pasic
2019-07-18 9:04 ` Cornelia Huck
2019-07-18 11:20 ` Halil Pasic
2019-07-18 14:47 ` Cornelia Huck
2019-07-18 13:15 ` Vivek Goyal
2019-07-18 14:30 ` Dan Williams
2019-07-22 10:51 ` Christian Borntraeger
2019-07-22 10:56 ` Dr. David Alan Gilbert
2019-07-22 11:20 ` Christian Borntraeger
2019-07-22 11:43 ` Cornelia Huck
2019-07-22 12:00 ` Christian Borntraeger
2019-07-22 12:08 ` David Hildenbrand
2019-07-29 13:20 ` Stefan Hajnoczi
2019-05-15 19:27 ` [PATCH v2 19/30] fuse: Keep a list of free dax memory ranges Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 20/30] fuse: Introduce setupmapping/removemapping commands Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 21/30] fuse, dax: Implement dax read/write operations Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 22/30] fuse, dax: add DAX mmap support Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 23/30] fuse: Define dax address space operations Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 24/30] fuse, dax: Take ->i_mmap_sem lock during dax page fault Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 25/30] fuse: Maintain a list of busy elements Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 26/30] fuse: Add logic to free up a memory range Vivek Goyal
[not found] ` <CAN+Pk99SNKSf+GjSQUUWt_eu1fSjTy_ByUOEQUXHi8zNqXY1zA@mail.gmail.com>
2019-05-20 12:53 ` Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 27/30] fuse: Release file in process context Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 28/30] fuse: Reschedule dax free work if too many EAGAIN attempts Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 29/30] fuse: Take inode lock for dax inode truncation Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 30/30] virtio-fs: Do not provide abort interface in fusectl Vivek Goyal
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190515192715.18000-3-vgoyal@redhat.com \
--to=vgoyal@redhat.com \
--cc=dgilbert@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@lists.01.org \
--cc=miklos@szeredi.hu \
--cc=stefanha@redhat.com \
--cc=swhiteho@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).