[ Upstream commit 23892d383b ]
Bug description and fix:
1. Write data to a file, say all 1s from offset 0 to 16.
2. Truncate the file to a smaller size, say 8 bytes.
3. Write new bytes (say 2s) from an offset past the original size of the
file, say at offset 20, for 4 bytes. This is supposed to create a "hole"
in the file, meaning that the bytes from offset 8 (where it was truncated
above) up to the new write at offset 20, should all be 0s (zeros).
4. Flush all caches using "echo 3 > /proc/sys/vm/drop_caches" (or unmount
and remount) the f/s.
5. Check the content of the file. It is wrong. The 1s that used to be
between bytes 9 and 16, before the truncation, have REAPPEARED (they should
be 0s).
We wrote a script and helper C program to reproduce the bug
(reproduce_jffs2_write_begin_issue.sh, write_file.c, and Makefile). We can
make them available to anyone.
The above example is shown when writing a small file within the same first
page. But the bug happens for larger files, as long as steps 1, 2, and 3
above all happen within the same page.
The problem was traced to the jffs2_write_begin code, where it goes into an
'if' statement intended to handle writes past the current EOF (i.e., writes
that may create a hole). The code computes a 'pageofs' that is the floor
of the write position (pos), aligned to the page size boundary. In other
words, 'pageofs' will never be larger than 'pos'. The code then sets the
internal jffs2_raw_inode->isize to the size of max(current inode size,
pageofs) but that is wrong: the new file size should be the 'pos', which is
larger than both the current inode size and pageofs.
Similarly, the code incorrectly sets the internal jffs2_raw_inode->dsize to
the difference between the pageofs minus current inode size; instead it
should be the current pos minus the current inode size. Finally,
inode->i_size was also set incorrectly.
The patch below fixes this bug. The bug was discovered using a new tool
for finding f/s bugs using model checking, called MCFS (Model Checking File
Systems).
Signed-off-by: Yifei Liu <yifeliu@cs.stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.stonybrook.edu>
Signed-off-by: Manish Adkar <madkar@cs.stonybrook.edu>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4c7c44ee16 upstream.
When we mount a jffs2 image, assume that the first few blocks of
the image are normal and contain at least one xattr-related inode,
but the next block is abnormal. As a result, an error is returned
in jffs2_scan_eraseblock(). jffs2_clear_xattr_subsystem() is then
called in jffs2_build_filesystem() and then again in
jffs2_do_fill_super().
Finally we can observe the following report:
==================================================================
BUG: KASAN: use-after-free in jffs2_clear_xattr_subsystem+0x95/0x6ac
Read of size 8 at addr ffff8881243384e0 by task mount/719
Call Trace:
dump_stack+0x115/0x16b
jffs2_clear_xattr_subsystem+0x95/0x6ac
jffs2_do_fill_super+0x84f/0xc30
jffs2_fill_super+0x2ea/0x4c0
mtd_get_sb+0x254/0x400
mtd_get_sb_by_nr+0x4f/0xd0
get_tree_mtd+0x498/0x840
jffs2_get_tree+0x25/0x30
vfs_get_tree+0x8d/0x2e0
path_mount+0x50f/0x1e50
do_mount+0x107/0x130
__se_sys_mount+0x1c5/0x2f0
__x64_sys_mount+0xc7/0x160
do_syscall_64+0x45/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Allocated by task 719:
kasan_save_stack+0x23/0x60
__kasan_kmalloc.constprop.0+0x10b/0x120
kasan_slab_alloc+0x12/0x20
kmem_cache_alloc+0x1c0/0x870
jffs2_alloc_xattr_ref+0x2f/0xa0
jffs2_scan_medium.cold+0x3713/0x4794
jffs2_do_mount_fs.cold+0xa7/0x2253
jffs2_do_fill_super+0x383/0xc30
jffs2_fill_super+0x2ea/0x4c0
[...]
Freed by task 719:
kmem_cache_free+0xcc/0x7b0
jffs2_free_xattr_ref+0x78/0x98
jffs2_clear_xattr_subsystem+0xa1/0x6ac
jffs2_do_mount_fs.cold+0x5e6/0x2253
jffs2_do_fill_super+0x383/0xc30
jffs2_fill_super+0x2ea/0x4c0
[...]
The buggy address belongs to the object at ffff8881243384b8
which belongs to the cache jffs2_xattr_ref of size 48
The buggy address is located 40 bytes inside of
48-byte region [ffff8881243384b8, ffff8881243384e8)
[...]
==================================================================
The triggering of the BUG is shown in the following stack:
-----------------------------------------------------------
jffs2_fill_super
jffs2_do_fill_super
jffs2_do_mount_fs
jffs2_build_filesystem
jffs2_scan_medium
jffs2_scan_eraseblock <--- ERROR
jffs2_clear_xattr_subsystem <--- free
jffs2_clear_xattr_subsystem <--- free again
-----------------------------------------------------------
An error is returned in jffs2_do_mount_fs(). If the error is returned
by jffs2_sum_init(), the jffs2_clear_xattr_subsystem() does not need to
be executed. If the error is returned by jffs2_build_filesystem(), the
jffs2_clear_xattr_subsystem() also does not need to be executed again.
So move jffs2_clear_xattr_subsystem() from 'out_inohash' to 'out_root'
to fix this UAF problem.
Fixes: aa98d7cf59 ("[JFFS2][XATTR] XATTR support on JFFS2 (version. 5)")
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit aa39cc6757 ]
GC task can deadlock in read_cache_page() because it may attempt
to release a page that is actually allocated by another task in
jffs2_write_begin().
The reason is that in jffs2_write_begin() there is a small window
a cache page is allocated for use but not set Uptodate yet.
This ends up with a deadlock between two tasks:
1) A task (e.g. file copy)
- jffs2_write_begin() locks a cache page
- jffs2_write_end() tries to lock "alloc_sem" from
jffs2_reserve_space() <-- STUCK
2) GC task (jffs2_gcd_mtd3)
- jffs2_garbage_collect_pass() locks "alloc_sem"
- try to lock the same cache page in read_cache_page() <-- STUCK
So to avoid this deadlock, hold "alloc_sem" in jffs2_write_begin()
while reading data in a cache page.
Signed-off-by: Kyeong Yoo <kyeong.yoo@alliedtelesis.co.nz>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Add a rcu argument to the ->get_acl() callback to allow
get_cached_acl_rcu() to call the ->get_acl() method in the next patch.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
JFFS2:
- Use splice_write()
- Fix for a slab-out-of-bounds bug
UBI:
- Fix for clang related warnings
- Code cleanup
UBIFS:
- Fix for inode rebirth at replay
- Set s_uuid
- Use zstd for default filesystem
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Merge tag 'for-linus-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull JFFS2, UBI and UBIFS updates from Richard Weinberger:
"JFFS2:
- Use splice_write()
- Fix for a slab-out-of-bounds bug
UBI:
- Fix for clang related warnings
- Code cleanup
UBIFS:
- Fix for inode rebirth at replay
- Set s_uuid
- Use zstd for default filesystem"
* tag 'for-linus-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubi: Remove unnecessary struct declaration
jffs2: Hook up splice_write callback
jffs2: avoid Wempty-body warnings
jffs2: Fix kasan slab-out-of-bounds problem
ubi: Fix fall-through warnings for Clang
ubifs: Report max LEB count at mount time
ubifs: Set s_uuid in super block to support ima/evm uuid options
ubifs: Default to zstd compression
ubifs: Only check replay with inode type to judge if inode linked
overlayfs using jffs2 as the upper filesystem would fail in some cases
since moving to v5.10. The test case used was to run 'touch' on a file
that exists in the lower fs, causing the modification time to be
updated. It returns EINVAL when the bug is triggered.
A bisection showed this was introduced in v5.9-rc1, with commit
36e2c7421f ("fs: don't allow splice read/write without explicit ops").
Reverting that commit restores the expected behaviour.
Some digging showed that this was due to jffs2 lacking an implementation
of splice_write. (For unknown reasons the warn_unsupported that should
trigger was not displaying any output).
Adding this patch resolved the issue and the test now passes.
Cc: stable@vger.kernel.org
Fixes: 36e2c7421f ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Lei YU <yulei.sh@bytedance.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Building with W=1 shows a few warnings for empty macros:
fs/jffs2/scan.c: In function 'jffs2_scan_xattr_node':
fs/jffs2/scan.c:378:66: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
378 | jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset);
| ^
fs/jffs2/scan.c: In function 'jffs2_scan_xref_node':
fs/jffs2/scan.c:434:65: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
434 | jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset);
| ^
fs/jffs2/scan.c: In function 'jffs2_scan_eraseblock':
fs/jffs2/scan.c:893:88: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
893 | jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
| ^
Change all these macros to 'do { } while (0)' statements to avoid the
warnings and make the code a little more robust.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
KASAN report a slab-out-of-bounds problem. The logs are listed below.
It is because in function jffs2_scan_dirent_node, we alloc "checkedlen+1"
bytes for fd->name and we check crc with length rd->nsize. If checkedlen
is less than rd->nsize, it will cause the slab-out-of-bounds problem.
jffs2: Dirent at *** has zeroes in name. Truncating to %d char
==================================================================
BUG: KASAN: slab-out-of-bounds in crc32_le+0x1ce/0x260 at addr ffff8800842cf2d1
Read of size 1 by task test_JFFS2/915
=============================================================================
BUG kmalloc-64 (Tainted: G B O ): kasan: bad access detected
-----------------------------------------------------------------------------
INFO: Allocated in jffs2_alloc_full_dirent+0x2a/0x40 age=0 cpu=1 pid=915
___slab_alloc+0x580/0x5f0
__slab_alloc.isra.24+0x4e/0x64
__kmalloc+0x170/0x300
jffs2_alloc_full_dirent+0x2a/0x40
jffs2_scan_eraseblock+0x1ca4/0x3b64
jffs2_scan_medium+0x285/0xfe0
jffs2_do_mount_fs+0x5fb/0x1bbc
jffs2_do_fill_super+0x245/0x6f0
jffs2_fill_super+0x287/0x2e0
mount_mtd_aux.isra.0+0x9a/0x144
mount_mtd+0x222/0x2f0
jffs2_mount+0x41/0x60
mount_fs+0x63/0x230
vfs_kern_mount.part.6+0x6c/0x1f4
do_mount+0xae8/0x1940
SyS_mount+0x105/0x1d0
INFO: Freed in jffs2_free_full_dirent+0x22/0x40 age=27 cpu=1 pid=915
__slab_free+0x372/0x4e4
kfree+0x1d4/0x20c
jffs2_free_full_dirent+0x22/0x40
jffs2_build_remove_unlinked_inode+0x17a/0x1e4
jffs2_do_mount_fs+0x1646/0x1bbc
jffs2_do_fill_super+0x245/0x6f0
jffs2_fill_super+0x287/0x2e0
mount_mtd_aux.isra.0+0x9a/0x144
mount_mtd+0x222/0x2f0
jffs2_mount+0x41/0x60
mount_fs+0x63/0x230
vfs_kern_mount.part.6+0x6c/0x1f4
do_mount+0xae8/0x1940
SyS_mount+0x105/0x1d0
entry_SYSCALL_64_fastpath+0x1e/0x97
Call Trace:
[<ffffffff815befef>] dump_stack+0x59/0x7e
[<ffffffff812d1d65>] print_trailer+0x125/0x1b0
[<ffffffff812d82c8>] object_err+0x34/0x40
[<ffffffff812dadef>] kasan_report.part.1+0x21f/0x534
[<ffffffff81132401>] ? vprintk+0x2d/0x40
[<ffffffff815f1ee2>] ? crc32_le+0x1ce/0x260
[<ffffffff812db41a>] kasan_report+0x26/0x30
[<ffffffff812d9fc1>] __asan_load1+0x3d/0x50
[<ffffffff815f1ee2>] crc32_le+0x1ce/0x260
[<ffffffff814764ae>] ? jffs2_alloc_full_dirent+0x2a/0x40
[<ffffffff81485cec>] jffs2_scan_eraseblock+0x1d0c/0x3b64
[<ffffffff81488813>] ? jffs2_scan_medium+0xccf/0xfe0
[<ffffffff81483fe0>] ? jffs2_scan_make_ino_cache+0x14c/0x14c
[<ffffffff812da3e9>] ? kasan_unpoison_shadow+0x35/0x50
[<ffffffff812da3e9>] ? kasan_unpoison_shadow+0x35/0x50
[<ffffffff812da462>] ? kasan_kmalloc+0x5e/0x70
[<ffffffff812d5d90>] ? kmem_cache_alloc_trace+0x10c/0x2cc
[<ffffffff818169fb>] ? mtd_point+0xf7/0x130
[<ffffffff81487dc9>] jffs2_scan_medium+0x285/0xfe0
[<ffffffff81487b44>] ? jffs2_scan_eraseblock+0x3b64/0x3b64
[<ffffffff812da3e9>] ? kasan_unpoison_shadow+0x35/0x50
[<ffffffff812da3e9>] ? kasan_unpoison_shadow+0x35/0x50
[<ffffffff812da462>] ? kasan_kmalloc+0x5e/0x70
[<ffffffff812d57df>] ? __kmalloc+0x12b/0x300
[<ffffffff812da462>] ? kasan_kmalloc+0x5e/0x70
[<ffffffff814a2753>] ? jffs2_sum_init+0x9f/0x240
[<ffffffff8148b2ff>] jffs2_do_mount_fs+0x5fb/0x1bbc
[<ffffffff8148ad04>] ? jffs2_del_noinode_dirent+0x640/0x640
[<ffffffff812da462>] ? kasan_kmalloc+0x5e/0x70
[<ffffffff81127c5b>] ? __init_rwsem+0x97/0xac
[<ffffffff81492349>] jffs2_do_fill_super+0x245/0x6f0
[<ffffffff81493c5b>] jffs2_fill_super+0x287/0x2e0
[<ffffffff814939d4>] ? jffs2_parse_options+0x594/0x594
[<ffffffff81819bea>] mount_mtd_aux.isra.0+0x9a/0x144
[<ffffffff81819eb6>] mount_mtd+0x222/0x2f0
[<ffffffff814939d4>] ? jffs2_parse_options+0x594/0x594
[<ffffffff81819c94>] ? mount_mtd_aux.isra.0+0x144/0x144
[<ffffffff81258757>] ? free_pages+0x13/0x1c
[<ffffffff814fa0ac>] ? selinux_sb_copy_data+0x278/0x2e0
[<ffffffff81492b35>] jffs2_mount+0x41/0x60
[<ffffffff81302fb7>] mount_fs+0x63/0x230
[<ffffffff8133755f>] ? alloc_vfsmnt+0x32f/0x3b0
[<ffffffff81337f2c>] vfs_kern_mount.part.6+0x6c/0x1f4
[<ffffffff8133ceec>] do_mount+0xae8/0x1940
[<ffffffff811b94e0>] ? audit_filter_rules.constprop.6+0x1d10/0x1d10
[<ffffffff8133c404>] ? copy_mount_string+0x40/0x40
[<ffffffff812cbf78>] ? alloc_pages_current+0xa4/0x1bc
[<ffffffff81253a89>] ? __get_free_pages+0x25/0x50
[<ffffffff81338993>] ? copy_mount_options.part.17+0x183/0x264
[<ffffffff8133e3a9>] SyS_mount+0x105/0x1d0
[<ffffffff8133e2a4>] ? copy_mnt_ns+0x560/0x560
[<ffffffff810e8391>] ? msa_space_switch_handler+0x13d/0x190
[<ffffffff81be184a>] entry_SYSCALL_64_fastpath+0x1e/0x97
[<ffffffff810e9274>] ? msa_space_switch+0xb0/0xe0
Memory state around the buggy address:
ffff8800842cf180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8800842cf200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8800842cf280: fc fc fc fc fc fc 00 00 00 00 01 fc fc fc fc fc
^
ffff8800842cf300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8800842cf380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Cc: stable@vger.kernel.org
Reported-by: Kunkun Xu <xukunkun1@huawei.com>
Signed-off-by: lizhe <lizhe67@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The TODO file here has not been updated for 14 years, and the function
development described in the file have been implemented or abandoned.
Its existence will mislead developers seeking to view outdated information.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
clang static analysis reports this problem
fs/jffs2/summary.c:794:31: warning: Use of memory after it is freed
c->summary->sum_list_head = temp->u.next;
^~~~~~~~~~~~
In jffs2_sum_write_data(), in a loop summary data is handles a node at
a time. When it has written out the node it is removed the summary list,
and the node is deleted. In the corner case when a
JFFS2_FEATURE_RWCOMPAT_COPY is seen, a call is made to
jffs2_sum_disable_collecting(). jffs2_sum_disable_collecting() deletes
the whole list which conflicts with the loop's deleting the list by parts.
To preserve the old behavior of stopping the write midway, bail out of
the loop after disabling summary collection.
Fixes: 6171586a7a ("[JFFS2] Correct handling of JFFS2_FEATURE_RWCOMPAT_COPY nodes.")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.
Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Set rp_size to zero will be ignore during remounting.
The method to identify whether we input a remounting option of
rp_size is to check if the rp_size input is zero. It can not work
well if we pass "rp_size=0".
This patch add a bool variable "set_rp_size" to fix this problem.
Reported-by: Jubin Zhong <zhongjubin@huawei.com>
Signed-off-by: lizhe <lizhe67@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The jffs2 mount options will be ignored when remounting jffs2.
It can be easily reproduced with the steps listed below.
1. mount -t jffs2 -o compr=none /dev/mtdblockx /mnt
2. mount -o remount compr=zlib /mnt
Since ec10a24f10, the option parsing happens before fill_super and
then pass fc, which contains the options parsing results, to function
jffs2_reconfigure during remounting. But function jffs2_reconfigure do
not update c->mount_opts.
This patch add a function jffs2_update_mount_opts to fix this problem.
By the way, I notice that tmpfs use the same way to update remounting
options. If it is necessary to unify them?
Cc: <stable@vger.kernel.org>
Fixes: ec10a24f10 ("vfs: Convert jffs2 to use the new mount API")
Signed-off-by: lizhe <lizhe67@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The log of this problem is:
jffs2: Error garbage collecting node at 0x***!
jffs2: No space for garbage collection. Aborting GC thread
This is because GC believe that it do nothing, so it abort.
After going over the image of jffs2, I find a scene that
can trigger this problem stably.
The scene is: there is a normal dirent node at summary-area,
but abnormal at corresponding not-summary-area with error
name_crc.
The reason that GC exit abnormally is because it find that
abnormal dirent node to GC, but when it goes to function
jffs2_add_fd_to_list, it cannot meet the condition listed
below:
if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name))
So no node is marked obsolete, statistical information of
erase_block do not change, which cause GC exit abnormally.
The root cause of this problem is: we do not check the
name_crc of the abnormal dirent node with summary is enabled.
Noticed that in function jffs2_scan_dirent_node, we use
function jffs2_scan_dirty_space to deal with the dirent
node with error name_crc. So this patch add a checking
code in function read_direntry to ensure the correctness
of dirent node. If checked failed, the dirent node will
be marked obsolete so GC will pass this node and this
problem will be fixed.
Cc: <stable@vger.kernel.org>
Signed-off-by: Zhe Li <lizhe67@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
When debug (print) macros are not enabled, change them to use the
no_printk() macro instead of <nothing>. This fixes gcc warnings when
-Wextra is used:
../fs/jffs2/nodelist.c:255:37: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
../fs/jffs2/nodelist.c:278:38: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
../fs/jffs2/nodelist.c:558:52: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]
../fs/jffs2/xattr.c:1247:58: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../fs/jffs2/xattr.c:1281:65: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
Builds without warnings on all 3 levels of CONFIG_JFFS2_FS_DEBUG.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Richard Weinberger <richard@nod.at>
JFFS2:
- Fix for a corner case while mounting
- Fix for an use-after-free issue
UBI:
- Fix for a memory load while attaching
- Don't produce an anchor PEB with fastmap being disabled
UBIFS:
- Fix for orphan inode logic
- Spelling fixes
- New mount option to specify filesystem version
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Merge tag 'for-linus-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull JFFS2, UBI and UBIFS updates from Richard Weinberger:
"JFFS2:
- Fix for a corner case while mounting
- Fix for an use-after-free issue
UBI:
- Fix for a memory load while attaching
- Don't produce an anchor PEB with fastmap being disabled
UBIFS:
- Fix for orphan inode logic
- Spelling fixes
- New mount option to specify filesystem version"
* tag 'for-linus-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
jffs2: fix UAF problem
jffs2: fix jffs2 mounting failure
ubifs: Fix wrong orphan node deletion in ubifs_jnl_update|rename
ubi: fastmap: Free fastmap next anchor peb during detach
ubi: fastmap: Don't produce the initial next anchor PEB when fastmap is disabled
ubifs: misc.h: delete a duplicated word
ubifs: add option to specify version for new file systems
The log of UAF problem is listed below.
BUG: KASAN: use-after-free in jffs2_rmdir+0xa4/0x1cc [jffs2] at addr c1f165fc
Read of size 4 by task rm/8283
=============================================================================
BUG kmalloc-32 (Tainted: P B O ): kasan: bad access detected
-----------------------------------------------------------------------------
INFO: Allocated in 0xbbbbbbbb age=3054364 cpu=0 pid=0
0xb0bba6ef
jffs2_write_dirent+0x11c/0x9c8 [jffs2]
__slab_alloc.isra.21.constprop.25+0x2c/0x44
__kmalloc+0x1dc/0x370
jffs2_write_dirent+0x11c/0x9c8 [jffs2]
jffs2_do_unlink+0x328/0x5fc [jffs2]
jffs2_rmdir+0x110/0x1cc [jffs2]
vfs_rmdir+0x180/0x268
do_rmdir+0x2cc/0x300
ret_from_syscall+0x0/0x3c
INFO: Freed in 0x205b age=3054364 cpu=0 pid=0
0x2e9173
jffs2_add_fd_to_list+0x138/0x1dc [jffs2]
jffs2_add_fd_to_list+0x138/0x1dc [jffs2]
jffs2_garbage_collect_dirent.isra.3+0x21c/0x288 [jffs2]
jffs2_garbage_collect_live+0x16bc/0x1800 [jffs2]
jffs2_garbage_collect_pass+0x678/0x11d4 [jffs2]
jffs2_garbage_collect_thread+0x1e8/0x3b0 [jffs2]
kthread+0x1a8/0x1b0
ret_from_kernel_thread+0x5c/0x64
Call Trace:
[c17ddd20] [c02452d4] kasan_report.part.0+0x298/0x72c (unreliable)
[c17ddda0] [d2509680] jffs2_rmdir+0xa4/0x1cc [jffs2]
[c17dddd0] [c026da04] vfs_rmdir+0x180/0x268
[c17dde00] [c026f4e4] do_rmdir+0x2cc/0x300
[c17ddf40] [c001a658] ret_from_syscall+0x0/0x3c
The root cause is that we don't get "jffs2_inode_info.sem" before
we scan list "jffs2_inode_info.dents" in function jffs2_rmdir.
This patch add codes to get "jffs2_inode_info.sem" before we scan
"jffs2_inode_info.dents" to slove the UAF problem.
Signed-off-by: Zhe Li <lizhe67@huawei.com>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Thanks for the advice mentioned in the email.
This is my v3 patch for this problem.
Mounting jffs2 on nand flash will get message "failed: I/O error"
with the steps listed below.
1.umount jffs2
2.erase nand flash
3.mount jffs2 on it (this mounting operation will be successful)
4.do chown or chmod to the mount point directory
5.umount jffs2
6.mount jffs2 on nand flash
After step 6, we will get message "mount ... failed: I/O error".
Typical image of this problem is like:
Empty space found from 0x00000000 to 0x008a0000
Inode node at xx, totlen 0x00000044, #ino 1, version 1, isize 0...
The reason for this mounting failure is that at the end of function
jffs2_scan_medium(), jffs2 will check the used_size and some info
of nr_blocks.If conditions are met, it will return -EIO.
The detail is that, in the steps listed above, step 4 will write
jffs2_raw_inode into flash without jffs2_raw_dirent, which will
cause that there are some jffs2_raw_inode but no jffs2_raw_dirent
on flash. This will meet the condition at the end of function
jffs2_scan_medium() and return -EIO if we umount jffs2 and mount it
again.
We notice that jffs2 add the value of c->unchecked_size if we find
an inode node while mounting. And jffs2 will never add the value of
c->unchecked_size in other situations. So this patch add one more
condition about c->unchecked_size of the judgement to fix this problem.
Signed-off-by: Zhe Li <lizhe67@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Unused now.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Don't do a single array; attach them to fsparam_enum() entry
instead. And don't bother trying to embed the names into those -
it actually loses memory, with no real speedup worth mentioning.
Simplifies validation as well.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This reverts commit f2538f9993. The patch
stopped JFFS2 from being able to mount an existing filesystem with the
following errors:
jffs2: error: (77) jffs2_build_inode_fragtree: Add node to tree failed -22
jffs2: error: (77) jffs2_do_read_inode_internal: Failed to build final fragtree for inode #5377: error -22
Fixes: f2538f9993 ("jffs2: Fix possible null-pointer dereferences...")
Cc: stable@vger.kernel.org
Suggested-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull jffs2 fix from Al Viro:
"braino fix for mount API conversion for jffs2"
* 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
jffs2: Fix mounting under new mount API
The mounting of jffs2 is broken due to the changes from the new mount API
because it specifies a "source" operation, but then doesn't actually
process it. But because it specified it, it doesn't return -ENOPARAM and
the caller doesn't process it either and the source gets lost.
Fix this by simply removing the source parameter from jffs2 and letting the
VFS deal with it in the default manner.
To test it, enable CONFIG_MTD_MTDRAM and allow the default size and erase
block size parameters, then try and mount the /dev/mtdblock<N> file that
that creates as jffs2. No need to initialise it.
Fixes: ec10a24f10 ("vfs: Convert jffs2 to use the new mount API")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Richard Weinberger <richard@nod.at>
cc: linux-mtd@lists.infradead.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
UBI:
- Be less stupid when placing a fastmap anchor
- Try harder to get an empty PEB in case of contention
- Make ubiblock to warn if image is not a multiple of 512
UBIFS:
- Various fixes in error paths
JFFS2:
- Various fixes in error paths
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Merge tag 'upstream-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull UBI, UBIFS and JFFS2 updates from Richard Weinberger:
"UBI:
- Be less stupid when placing a fastmap anchor
- Try harder to get an empty PEB in case of contention
- Make ubiblock to warn if image is not a multiple of 512
UBIFS:
- Various fixes in error paths
JFFS2:
- Various fixes in error paths"
* tag 'upstream-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
jffs2: Fix memory leak in jffs2_scan_eraseblock() error path
jffs2: Remove jffs2_gc_fetch_page and jffs2_gc_release_page
jffs2: Fix possible null-pointer dereferences in jffs2_add_frag_to_fragtree()
ubi: block: Warn if volume size is not multiple of 512
ubifs: Fix memory leak bug in alloc_ubifs_info() error path
ubifs: Fix memory leak in __ubifs_node_verify_hmac error path
ubifs: Fix memory leak in read_znode() error path
ubi: ubi_wl_get_peb: Increase the number of attempts while getting PEB
ubi: Don't do anchor move within fastmap area
ubifs: Remove redundant assignment to pointer fname
Pull misc mount API conversions from Al Viro:
"Conversions to new API for shmem and friends and for mount_mtd()-using
filesystems.
As for the rest of the mount API conversions in -next, some of them
belong in the individual trees (e.g. binderfs one should definitely go
through android folks, after getting redone on top of their changes).
I'm going to drop those and send the rest (trivial ones + stuff ACKed
by maintainers) in a separate series - by that point they are
independent from each other.
Some stuff has already migrated into individual trees (NFS conversion,
for example, or FUSE stuff, etc.); those presumably will go through
the regular merges from corresponding trees."
* 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: Make fs_parse() handle fs_param_is_fd-type params better
vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
shmem_parse_one(): switch to use of fs_parse()
shmem_parse_options(): take handling a single option into a helper
shmem_parse_options(): don't bother with mpol in separate variable
shmem_parse_options(): use a separate structure to keep the results
make shmem_fill_super() static
make ramfs_fill_super() static
devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()
vfs: Convert squashfs to use the new mount API
mtd: Kill mount_mtd()
vfs: Convert jffs2 to use the new mount API
vfs: Convert cramfs to use the new mount API
vfs: Convert romfs to use the new mount API
vfs: Add a single-or-reconfig keying to vfs_get_super()
In jffs2_scan_eraseblock(), 'sumptr' is allocated through kmalloc() if
'sumlen' is larger than 'buf_size'. However, it is not deallocated in the
following execution if jffs2_fill_scan_buf() fails, leading to a memory
leak bug. To fix this issue, free 'sumptr' before returning the error.
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Richard Weinberger <richard@nod.at>
Merge these two helpers into the only callers to get rid of some
amazingly bad calling conventions.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
In jffs2_add_frag_to_fragtree(), there is an if statement on line 223 to
check whether "this" is NULL:
if (this)
When "this" is NULL, it is used at several places, such as on line 249:
if (this->node)
and on line 260:
if (newfrag->ofs > this->ofs)
Thus possible null-pointer dereferences may occur.
To fix these bugs, -EINVAL is returned when "this" is NULL.
These bugs are found by a static analysis tool STCheck written by us.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Convert the jffs2 filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: linux-mtd@lists.infradead.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix the callback jffs2 passes to read_cache_page to actually have the
proper type expected. Casting around function pointers can easily hide
typing bugs, and defeats control flow protection.
Link: http://lkml.kernel.org/r/20190520055731.24538-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hi Linus,
This is my very first pull-request. I've been working full-time as
a kernel developer for more than two years now. During this time I've
been fixing bugs reported by Coverity all over the tree and, as part
of my work, I'm also contributing to the KSPP. My work in the kernel
community has been supervised by Greg KH and Kees Cook.
OK. So, after the quick introduction above, please, pull the following
patches that mark switch cases where we are expecting to fall through.
These patches are part of the ongoing efforts to enable -Wimplicit-fallthrough.
They have been ignored for a long time (most of them more than 3 months,
even after pinging multiple times), which is the reason why I've created
this tree. Most of them have been baking in linux-next for a whole development
cycle. And with Stephen Rothwell's help, we've had linux-next nag-emails
going out for newly introduced code that triggers -Wimplicit-fallthrough
to avoid gaining more of these cases while we work to remove the ones
that are already present.
I'm happy to let you know that we are getting close to completing this
work. Currently, there are only 32 of 2311 of these cases left to be
addressed in linux-next. I'm auditing every case; I take a look into
the code and analyze it in order to determine if I'm dealing with an
actual bug or a false positive, as explained here:
https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/
While working on this, I've found and fixed the following missing
break/return bugs, some of them introduced more than 5 years ago:
84242b82d87850b51b6c5e420fe63509186e5034b5be8531817264235ee7cc5034a5d2479826cc865340f23df8df997abeeb2f10d82373307b00c5e65d25ff7a54a7ed5b3e7dc24bfa8f21ad0eaee6199ba8376ce1dc586a60a1a8e9b186f14e57562b4860747828eac5b974bee9cc44ba91162c930e3d0a
Once this work is finish, we'll be able to universally enable
"-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
entering the kernel again.
Thanks
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
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Merge tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull Wimplicit-fallthrough updates from Gustavo A. R. Silva:
"Mark switch cases where we are expecting to fall through.
This is part of the ongoing efforts to enable -Wimplicit-fallthrough.
Most of them have been baking in linux-next for a whole development
cycle. And with Stephen Rothwell's help, we've had linux-next
nag-emails going out for newly introduced code that triggers
-Wimplicit-fallthrough to avoid gaining more of these cases while we
work to remove the ones that are already present.
We are getting close to completing this work. Currently, there are
only 32 of 2311 of these cases left to be addressed in linux-next. I'm
auditing every case; I take a look into the code and analyze it in
order to determine if I'm dealing with an actual bug or a false
positive, as explained here:
https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/
While working on this, I've found and fixed the several missing
break/return bugs, some of them introduced more than 5 years ago.
Once this work is finished, we'll be able to universally enable
"-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
entering the kernel again"
* tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits)
memstick: mark expected switch fall-throughs
drm/nouveau/nvkm: mark expected switch fall-throughs
NFC: st21nfca: Fix fall-through warnings
NFC: pn533: mark expected switch fall-throughs
block: Mark expected switch fall-throughs
ASN.1: mark expected switch fall-through
lib/cmdline.c: mark expected switch fall-throughs
lib: zstd: Mark expected switch fall-throughs
scsi: sym53c8xx_2: sym_nvram: Mark expected switch fall-through
scsi: sym53c8xx_2: sym_hipd: mark expected switch fall-throughs
scsi: ppa: mark expected switch fall-through
scsi: osst: mark expected switch fall-throughs
scsi: lpfc: lpfc_scsi: Mark expected switch fall-throughs
scsi: lpfc: lpfc_nvme: Mark expected switch fall-through
scsi: lpfc: lpfc_nportdisc: Mark expected switch fall-through
scsi: lpfc: lpfc_hbadisc: Mark expected switch fall-throughs
scsi: lpfc: lpfc_els: Mark expected switch fall-throughs
scsi: lpfc: lpfc_ct: Mark expected switch fall-throughs
scsi: imm: mark expected switch fall-throughs
scsi: csiostor: csio_wr: mark expected switch fall-through
...
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch fixes the following warnings:
fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=]
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
free the symlink body after the same RCU delay we have for freeing the
struct inode itself, so that traversal during RCU pathwalk wouldn't step
into freed memory.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Yifei Liu
Baokun Li
Kyeong Yoo
Miklos Szeredi
Linus Torvalds
Joel Stanley
Arnd Bergmann
lizhe
Wang Qing
Yang Yang
Tom Rix
Christian Brauner
Jamie Iles
Randy Dunlap
Gustavo A. R. Silva
Kees Cook
Al Viro
Eric Sandeen
David Howells
Wenwen Wang
Christoph Hellwig
Jia-Ju Bai
Deepa Dinamani
Thomas Gleixner
Gustavo A. R. Silva