Commit Graph

133 Commits

Author SHA1 Message Date
Justin Stitt 07f8230b4b init: replace deprecated strncpy with strscpy_pad
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

data_page wants to be NUL-terminated and NUL-padded, use strscpy_pad to
provide both of these. data_page no longer awkwardly relies on
init_mount to perform its NUL-termination, although that sanity check is
left unchanged.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc:  <linux-hardening@vger.kernel.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240402-strncpy-init-do_mounts-c-v1-1-e16d7bc20974@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
2024-04-30 10:34:29 -07:00
Christian Brauner 386dc41cf5
init: flush async file closing
When unpacking the initramfs or when mounting block devices we need to
ensure that any delayed fput() finished to prevent spurious errors.
The init process can be a proper kernel thread or a user mode helper.
In the latter case PF_KTHREAD isn't set. So we need to do both
flush_delayed_work() and task_work_run().

Since we'll port block device opening and closing to regular file open
and closing we need to ensure the same as for the initramfs. So just
make that a little helper.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Srikanth Aithal <sraithal@amd.com>
Link: https://lore.kernel.org/r/CA+G9fYttTwsbFuVq10igbSvP5xC6bf_XijM=mpUqrJV=uvUirQ@mail.gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-08 18:41:03 +01:00
Stefan Berger 21528c69a0 rootfs: Fix support for rootfstype= when root= is given
Documentation/filesystems/ramfs-rootfs-initramfs.rst states:

  If CONFIG_TMPFS is enabled, rootfs will use tmpfs instead of ramfs by
  default.  To force ramfs, add "rootfstype=ramfs" to the kernel command
  line.

This currently does not work when root= is provided since then
saved_root_name contains a string and rootfstype= is ignored. Therefore,
ramfs is currently always chosen when root= is provided.

The current behavior for rootfs's filesystem is:

   root=       | rootfstype= | chosen rootfs filesystem
   ------------+-------------+--------------------------
   unspecified | unspecified | tmpfs
   unspecified | tmpfs       | tmpfs
   unspecified | ramfs       | ramfs
    provided   | ignored     | ramfs

rootfstype= should be respected regardless whether root= is given,
as shown below:

   root=       | rootfstype= | chosen rootfs filesystem
   ------------+-------------+--------------------------
   unspecified | unspecified | tmpfs  (as before)
   unspecified | tmpfs       | tmpfs  (as before)
   unspecified | ramfs       | ramfs  (as before)
    provided   | unspecified | ramfs  (compatibility with before)
    provided   | tmpfs       | tmpfs  (new)
    provided   | ramfs       | ramfs  (new)

This table represents the new behavior.

Fixes: 6e19eded36 ("initmpfs: use initramfs if rootfstype= or root= specified")
Cc: <stable@vger.kernel.org>
Signed-off-by: Rob Landley <rob@landley.net>
Link: https://lore.kernel.org/lkml/8244c75f-445e-b15b-9dbf-266e7ca666e2@landley.net/
Reviewed-and-Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Link: https://lore.kernel.org/r/20231120011248.396012-1-stefanb@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-07 10:29:21 +09:00
Jianyong Wu 84d2b69623
init/mount: print pretty name of root device when panics
Given a wrong root device, current log may not give the pretty name
which is useful to locate root cause.

For example, there are 2 blk devs in a VM, /dev/vda which has 2 partitials
/dev/vda1 and /dev/vda2 and /dev/vdb which is blank. /dev/vda2 is the
right root dev. When set "root=/dev/vdb", we get error log:

[    0.635575] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(254,16)

It's not straightforward to find out the root cause as there is lack of
the root devive name therefore hard for people to get those info from the
device number, in the example, (254,16).

It is more comprehensive way to hint the root cause if pretty name is
given here, like:

[    0.559887] Kernel panic - not syncing: VFS: Unable to mount root fs on "/dev/vdb" or unknown-block(254,16)

Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Message-Id: <20230907091025.3436878-1-jianyong.wu@arm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-19 11:02:46 +02:00
Loic Poulain 45071e1c28 init: Add support for rootwait timeout parameter
Add an optional timeout arg to 'rootwait' as the maximum time in
seconds to wait for the root device to show up before attempting
forced mount of the root filesystem.

Use case:
In case of device mapper usage for the rootfs (e.g. root=/dev/dm-0),
if the mapper is not able to create the virtual block for any reason
(wrong arguments, bad dm-verity signature, etc), the `rootwait` param
causes the kernel to wait forever. It may however be desirable to only
wait for a given time and then panic (force mount) to cause device reset.
This gives the bootloader a chance to detect the problem and to take some
measures, such as marking the booted partition as bad (for A/B case) or
entering a recovery mode.

In success case, mounting happens as soon as the root device is ready,
unlike the existing 'rootdelay' parameter which performs an unconditional
pause.

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Message-Id: <20230813082349.513386-1-loic.poulain@linaro.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-08-15 11:34:23 +02:00
Linus Torvalds 77b1a7f7a0 - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in
top-level directories.
 
 - Douglas Anderson has added a new "buddy" mode to the hardlockup
   detector.  It permits the detector to work on architectures which
   cannot provide the required interrupts, by having CPUs periodically
   perform checks on other CPUs.
 
 - Zhen Lei has enhanced kexec's ability to support two crash regions.
 
 - Petr Mladek has done a lot of cleanup on the hard lockup detector's
   Kconfig entries.
 
 - And the usual bunch of singleton patches in various places.
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Merge tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-mm updates from Andrew Morton:

 - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in top-level
   directories

 - Douglas Anderson has added a new "buddy" mode to the hardlockup
   detector. It permits the detector to work on architectures which
   cannot provide the required interrupts, by having CPUs periodically
   perform checks on other CPUs

 - Zhen Lei has enhanced kexec's ability to support two crash regions

 - Petr Mladek has done a lot of cleanup on the hard lockup detector's
   Kconfig entries

 - And the usual bunch of singleton patches in various places

* tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  kernel/time/posix-stubs.c: remove duplicated include
  ocfs2: remove redundant assignment to variable bit_off
  watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY
  powerpc: move arch_trigger_cpumask_backtrace from nmi.h to irq.h
  devres: show which resource was invalid in __devm_ioremap_resource()
  watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH
  watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64
  watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific
  watchdog/hardlockup: declare arch_touch_nmi_watchdog() only in linux/nmi.h
  watchdog/hardlockup: make the config checks more straightforward
  watchdog/hardlockup: sort hardlockup detector related config values a logical way
  watchdog/hardlockup: move SMP barriers from common code to buddy code
  watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY
  watchdog/buddy: don't copy the cpumask in watchdog_next_cpu()
  watchdog/buddy: cleanup how watchdog_buddy_check_hardlockup() is called
  watchdog/hardlockup: remove softlockup comment in touch_nmi_watchdog()
  watchdog/hardlockup: in watchdog_hardlockup_check() use cpumask_copy()
  watchdog/hardlockup: don't use raw_cpu_ptr() in watchdog_hardlockup_kick()
  watchdog/hardlockup: HAVE_NMI_WATCHDOG must implement watchdog_hardlockup_probe()
  watchdog/hardlockup: keep kernel.nmi_watchdog sysctl as 0444 if probe fails
  ...
2023-06-28 10:59:38 -07:00
Linus Torvalds a0433f8cae for-6.5/block-2023-06-23
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Merge tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull request via Keith:
      - Various cleanups all around (Irvin, Chaitanya, Christophe)
      - Better struct packing (Christophe JAILLET)
      - Reduce controller error logs for optional commands (Keith)
      - Support for >=64KiB block sizes (Daniel Gomez)
      - Fabrics fixes and code organization (Max, Chaitanya, Daniel
        Wagner)

 - bcache updates via Coly:
      - Fix a race at init time (Mingzhe Zou)
      - Misc fixes and cleanups (Andrea, Thomas, Zheng, Ye)

 - use page pinning in the block layer for dio (David)

 - convert old block dio code to page pinning (David, Christoph)

 - cleanups for pktcdvd (Andy)

 - cleanups for rnbd (Guoqing)

 - use the unchecked __bio_add_page() for the initial single page
   additions (Johannes)

 - fix overflows in the Amiga partition handling code (Michael)

 - improve mq-deadline zoned device support (Bart)

 - keep passthrough requests out of the IO schedulers (Christoph, Ming)

 - improve support for flush requests, making them less special to deal
   with (Christoph)

 - add bdev holder ops and shutdown methods (Christoph)

 - fix the name_to_dev_t() situation and use cases (Christoph)

 - decouple the block open flags from fmode_t (Christoph)

 - ublk updates and cleanups, including adding user copy support (Ming)

 - BFQ sanity checking (Bart)

 - convert brd from radix to xarray (Pankaj)

 - constify various structures (Thomas, Ivan)

 - more fine grained persistent reservation ioctl capability checks
   (Jingbo)

 - misc fixes and cleanups (Arnd, Azeem, Demi, Ed, Hengqi, Hou, Jan,
   Jordy, Li, Min, Yu, Zhong, Waiman)

* tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux: (266 commits)
  scsi/sg: don't grab scsi host module reference
  ext4: Fix warning in blkdev_put()
  block: don't return -EINVAL for not found names in devt_from_devname
  cdrom: Fix spectre-v1 gadget
  block: Improve kernel-doc headers
  blk-mq: don't insert passthrough request into sw queue
  bsg: make bsg_class a static const structure
  ublk: make ublk_chr_class a static const structure
  aoe: make aoe_class a static const structure
  block/rnbd: make all 'class' structures const
  block: fix the exclusive open mask in disk_scan_partitions
  block: add overflow checks for Amiga partition support
  block: change all __u32 annotations to __be32 in affs_hardblocks.h
  block: fix signed int overflow in Amiga partition support
  block: add capacity validation in bdev_add_partition()
  block: fine-granular CAP_SYS_ADMIN for Persistent Reservation
  block: disallow Persistent Reservation on partitions
  reiserfs: fix blkdev_put() warning from release_journal_dev()
  block: fix wrong mode for blkdev_get_by_dev() from disk_scan_partitions()
  block: document the holder argument to blkdev_get_by_path
  ...
2023-06-26 12:47:20 -07:00
Angus Chen 6aee6723f1 init: add bdev fs printk if mount_block_root failed
Booting with the QEMU command line:
"qemu-system-x86_64 -append root=/dev/vda rootfstype=ext4 ..."
will panic if ext4 is not builtin and a request to load the ext4 module
fails.

[    1.729006] VFS: Cannot open root device "vda" or unknown-block(253,0): error -19
[    1.730603] Please append a correct "root=" boot option; here are the available partitions:
[    1.732323] fd00          256000 vda
[    1.732329]  driver: virtio_blk
[    1.734194] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(253,0)
[    1.734771] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0-rc2+ #53
[    1.735194] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
[    1.735772] Call Trace:
[    1.735950]  <TASK>
[    1.736113]  dump_stack_lvl+0x32/0x50
[    1.736367]  panic+0x108/0x310
[    1.736570]  mount_block_root+0x161/0x310
[    1.736849]  ? rdinit_setup+0x40/0x40
[    1.737088]  prepare_namespace+0x10c/0x180
[    1.737393]  kernel_init_freeable+0x354/0x450
[    1.737707]  ? rest_init+0xd0/0xd0
[    1.737945]  kernel_init+0x16/0x130
[    1.738196]  ret_from_fork+0x1f/0x30

As a hint, print all the bdev fstypes which are available.

[akpm@linux-foundation.org: fix spelling in printk message]
Link: https://lkml.kernel.org/r/20230518035321.1672-1-angus.chen@jaguarmicro.com
Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 17:44:17 -07:00
Arnd Bergmann 73648e6fa7 init: move cifs_root_data() prototype into linux/mount.h
cifs_root_data() is defined in cifs and called from early init code, but
lacks a global prototype:

fs/cifs/cifsroot.c:83:12: error: no previous prototype for 'cifs_root_data'

Move the declaration from do_mounts.c into an appropriate header.

Link: https://lkml.kernel.org/r/20230517131102.934196-13-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 17:44:16 -07:00
Christoph Hellwig 702f3189e4 block: move the code to do early boot lookup of block devices to block/
Create a new block/early-lookup.c to keep the early block device lookup
code instead of having this code sit with the early mount code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:57:40 -06:00
Christoph Hellwig 079caa35f7 init: clear root_wait on all invalid root= strings
Instead of only clearing root_wait in devt_from_partuuid when the UUID
format was invalid, do that in parse_root_device for all strings that
failed to parse.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:57:40 -06:00
Christoph Hellwig cf056a4312 init: improve the name_to_dev_t interface
name_to_dev_t has a very misleading name, that doesn't make clear
it should only be used by the early init code, and also has a bad
calling convention that doesn't allow returning different kinds of
errors.  Rename it to early_lookup_bdev to make the use case clear,
and return an errno, where -EINVAL means the string could not be
parsed, and -ENODEV means it the string was valid, but there was
no device found for it.

Also stub out the whole call for !CONFIG_BLOCK as all the non-block
root cases are always covered in the caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:56:46 -06:00
Christoph Hellwig c0c1a7dcb6 init: move the nfs/cifs/ram special cases out of name_to_dev_t
The nfs/cifs/ram special case only needs to be parsed once, and only in
the boot code.  Move them out of name_to_dev_t and into
prepare_namespace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig 3701c600a3 init: factor the root_wait logic in prepare_namespace into a helper
The root_wait logic is a bit obsfucated right now.  Expand it and move it
into a helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig 07d63cbb67 init: handle ubi/mtd root mounting like all other root types
Assign a Root_Generic magic value for UBI/MTD root and handle the root
mounting in mount_root like all other root types.  Besides making the
code more clear this also means that UBI/MTD root can be used together
with an initrd (not that anyone should care).

Also factor parsing of the root name into a helper now that it can
be easily done and will get more complicated with subsequent patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig 73231b58b1 init: don't remove the /dev/ prefix from error messages
Remove the code that drops the /dev/ prefix from root_device_name, which
is only used for error messages when mounting the root device fails.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig c8643c72bc init: pass root_device_name explicitly
Instead of declaring root_device_name as a global variable pass it as an
argument to the functions using it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig a6a41d39c2 init: refactor mount_root
Provide stubs for all the lower level mount helpers, and just switch
on ROOT_DEV in the main function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig e3102722ff init: rename mount_block_root to mount_root_generic
mount_block_root is also used to mount non-block file systems, so give
it a better name.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230531125535.676098-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Christoph Hellwig aa5f6ed8c2 driver core: return bool from driver_probe_done
bool is the most sensible return value for a yes/no return.  Also
add __init as this funtion is only called from the early boot code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230531125535.676098-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 10:55:20 -06:00
Yihuan Pan 26e293f73f init: remove unused names parameter in split_fs_names()
The split_fs_names() function takes a names parameter, but the function
actually uses the root_fs_names global variable instead. This names
parameter is not used in the function, so it can be safely removed.

This change does not affect the functionality of split_fs_names() or any
other part of the kernel.

Signed-off-by: Yihuan Pan <xun794@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Message-Id: <4lsiigvaw4lxcs37rlhgepv77xyxym6krkqcpc3xfncnswok3y@b67z3b44orar>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-06-05 10:45:31 +02:00
Wolfram Sang a1d3a6d9f2 init: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818210200.8203-1-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11 21:55:10 -07:00
Christoph Hellwig 322cbb50de block: remove genhd.h
There is no good reason to keep genhd.h separate from the main blkdev.h
header that includes it.  So fold the contents of genhd.h into blkdev.h
and remove genhd.h entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Leon Romanovsky 40c8ee67cf init: don't panic if mount_nodev_root failed
Attempt to mount 9p file system as root gives the following kernel panic:

 9pnet_virtio: no channels available for device root
 Kernel panic - not syncing: VFS: Unable to mount root "root" (9p), err=-2
 CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc1+ #127
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 Call Trace:
  dump_stack_lvl+0x45/0x59
  panic+0x1e2/0x44b
  ? __warn_printk+0xf3/0xf3
  ? free_unref_page+0x2d4/0x4a0
  ? trace_hardirqs_on+0x32/0x120
  ? free_unref_page+0x2d4/0x4a0
  mount_root+0x189/0x1e0
  prepare_namespace+0x136/0x165
  kernel_init_freeable+0x3b8/0x3cb
  ? rest_init+0x2e0/0x2e0
  kernel_init+0x19/0x130
  ret_from_fork+0x1f/0x30
 Kernel Offset: disabled
 ---[ end Kernel panic - not syncing: VFS: Unable to mount root "root" (9p), err=-2 ]---

QEMU command line:
 "qemu-system-x86_64 -append root=/dev/root rw rootfstype=9p rootflags=trans=virtio ..."

This error is because root_device_name is truncated in prepare_namespace() from
being "/dev/root" to be "root" prior to call to mount_nodev_root().

As a solution, don't treat errors in mount_nodev_root() as errors that
require panics and allow failback to the mount flow that existed before
patch citied in Fixes tag.

Fixes: f9259be6a9 ("init: allow mounting arbitrary non-blockdevice filesystems as root")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-09-19 22:24:52 -04:00
Vivek Goyal b51593c4cd init/do_mounts.c: Harden split_fs_names() against buffer overflow
split_fs_names() currently takes comma separate list of filesystems
and converts it into individual filesystem strings. Pleaces these
strings in the input buffer passed by caller and returns number of
strings.

If caller manages to pass input string bigger than buffer, then we
can write beyond the buffer. Or if string just fits buffer, we will
still write beyond the buffer as we append a '\0' byte at the end.

Pass size of input buffer to split_fs_names() and put enough checks
in place so such buffer overrun possibilities do not occur.

This patch does few things.

- Add a parameter "size" to split_fs_names(). This specifies size
  of input buffer.

- Use strlcpy() (instead of strcpy()) so that we can't go beyond
  buffer size. If input string "names" is larger than passed in
  buffer, input string will be truncated to fit in buffer.

- Stop appending extra '\0' character at the end and avoid one
  possibility of going beyond the input buffer size.

- Do not use extra loop to count number of strings.

- Previously if one passed "rootfstype=foo,,bar", split_fs_names()
  will return only 1 string "foo" (and "bar" will be truncated
  due to extra ,). After this patch, now split_fs_names() will
  return 3 strings ("foo", zero-sized-string, and "bar").

  Callers of split_fs_names() have been modified to check for
  zero sized string and skip to next one.

Reported-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-09-19 22:24:49 -04:00
Linus Torvalds e2e694b9e6 Merge branch 'work.init' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull root filesystem type handling updates from Al Viro:
 "Teach init/do_mounts.c to handle non-block filesystems, hopefully
  preventing even more special-cased kludges (such as root=/dev/nfs,
  etc)"

* 'work.init' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: simplify get_filesystem_list / get_all_fs_names
  init: allow mounting arbitrary non-blockdevice filesystems as root
  init: split get_fs_names
2021-09-09 12:38:18 -07:00
Christoph Hellwig c4b2b7d150 block: remove CONFIG_DEBUG_BLOCK_EXT_DEVT
This might have been a neat debug aid when the extended dev_t was
added, but that time is long gone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210824075216.1179406-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-24 06:42:40 -06:00
Christoph Hellwig 6e7c1770a2 fs: simplify get_filesystem_list / get_all_fs_names
Just output the '\0' separate list of supported file systems for block
devices directly rather than going through a pointless round of string
manipulation.

Based on an earlier patch from Al Viro <viro@zeniv.linux.org.uk>.

Vivek:
Modified list_bdev_fs_names() and split_fs_names() to return number of
null terminted strings to caller. Callers now use that information to
loop through all the strings instead of relying on one extra null char
being present at the end.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-08-23 01:25:40 -04:00
Christoph Hellwig f9259be6a9 init: allow mounting arbitrary non-blockdevice filesystems as root
Currently the only non-blockdevice filesystems that can be used as the
initial root filesystem are NFS and CIFS, which use the magic
"root=/dev/nfs" and "root=/dev/cifs" syntax that requires the root
device file system details to come from filesystem specific kernel
command line options.

Add a little bit of new code that allows to just pass arbitrary
string mount options to any non-blockdevice filesystems so that it can
be mounted as the root file system.

For example a virtiofs root file system can be mounted using the
following syntax:

"root=myfs rootfstype=virtiofs rw"

Based on an earlier patch from Vivek Goyal <vgoyal@redhat.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-08-23 01:25:40 -04:00
Christoph Hellwig e24d12b744 init: split get_fs_names
Split get_fs_names into one function that splits up the command line
argument, and one that gets the list of all registered file systems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-08-23 01:25:40 -04:00
Christoph Hellwig c97d93c31e block: factor out a part_devt helper
Add a helper to find the dev_t for a disk + partno tuple.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210525061301.2242282-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01 07:45:49 -06:00
Christoph Hellwig 0d02129e76 block: merge struct block_device and struct hd_struct
Instead of having two structures that represent each block device with
different life time rules, merge them into a single one.  This also
greatly simplifies the reference counting rules, as we can use the inode
reference count as the main reference count for the new struct
block_device, with the device model reference front ending it for device
model interaction.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:40 -07:00
Christoph Hellwig 41e5c81984 block: remove the partno field from struct hd_struct
Just use the bd_partno field in struct block_device everywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:40 -07:00
Christoph Hellwig 231926dbf0 block: move the partition_meta_info to struct block_device
Move the partition_meta_info to struct block_device in preparation for
killing struct hd_struct.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:40 -07:00
Christoph Hellwig 013b0e96ae init: cleanup match_dev_by_uuid and match_dev_by_label
Avoid a totally pointless goto label, and use the same style of
comparism for both helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig e036bb8e0c init: refactor devt_from_partuuid
The code in devt_from_partuuid is very convoluted.  Refactor a bit by
sanitizing the goto and variable name usage.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig c2637e80a0 init: refactor name_to_dev_t
Split each case into a self-contained helper, and move the block
dependent code entirely under the pre-existing #ifdef CONFIG_BLOCK.
This allows to remove the blk_lookup_devt stub in genhd.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig 4b7ca5014c init: add an init_chroot helper
Add a simple helper to chroot with a kernel space file name and switch
the early init code over to it.  Remove the now unused ksys_chroot.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-31 08:17:52 +02:00
Christoph Hellwig db63f1e315 init: add an init_chdir helper
Add a simple helper to chdir with a kernel space file name and switch
the early init code over to it.  Remove the now unused ksys_chdir.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-31 08:17:52 +02:00
Christoph Hellwig c60166f042 init: add an init_mount helper
Like do_mount, but takes a kernel pointer for the destination path.
Switch over the mounts in the init code and devtmpfs to it, which
just happen to work due to the implicit set_fs(KERNEL_DS) during early
init right now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-31 08:17:51 +02:00
Christoph Hellwig c8376994c8 initrd: remove support for multiple floppies
Remove the special handling for multiple floppies in the initrd code.
No one should be using floppies for booting these days. (famous last
words..)

Includes a spelling fix from Colin Ian King <colin.king@canonical.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-30 08:22:33 +02:00
Christoph Hellwig 4f5b246b37 md: move the early init autodetect code to drivers/md/
Just like the NFS and CIFS root code this better lives with the
driver it is tightly integrated with.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-16 15:34:47 +02:00
Christoph Hellwig ea3edd4dc2 block: remove __bdevname
There is no good reason for __bdevname to exist.  Just open code
printing the string in the callers.  For three of them the format
string can be trivially merged into existing printk statements,
and in init/do_mounts.c we can at least do the scnprintf once at
the start of the function, and unconditional of CONFIG_BLOCK to
make the output for tiny configfs a little more helpful.

Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-24 07:57:07 -06:00
Linus Torvalds 7de7de7ca0 Fix root mounting with no mount options
The "trivial conversion" in commit cccaa5e335 ("init: use do_mount()
instead of ksys_mount()") was totally broken, since it didn't handle the
case of a NULL mount data pointer.  And while I had "tested" it (and
presumably Dominik had too) that bug was hidden by me having options.

Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Reported-by: Ondřej Jirman <megi@xff.cz>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-16 08:42:39 -08:00
Dominik Brodowski cccaa5e335 init: use do_mount() instead of ksys_mount()
In prepare_namespace(), do_mount() can be used instead of ksys_mount()
as the first and third argument are const strings in the kernel, the
second and fourth argument are passed through anyway, and the fifth
argument is NULL.

In do_mount_root(), ksys_mount() is called with the first and third
argument being already kernelspace strings, which do not need to be
copied over from userspace to kernelspace (again). The second and
fourth arguments are passed through to do_mount() anyway. The fifth
argument, while already residing in kernelspace, needs to be put into
a page of its own. Then, do_mount() can be used instead of
ksys_mount().

Once this is done, there are no in-kernel users to ksys_mount() left,
which can therefore be removed.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2019-12-12 14:50:05 +01:00
Dominik Brodowski 5e787dbf65 devtmpfs: use do_mount() instead of ksys_mount()
In devtmpfs, do_mount() can be called directly instead of complex wrapping
by ksys_mount():
- the first and third arguments are const strings in the kernel,
  and do not need to be copied over from userspace;
- the fifth argument is NULL, and therefore no page needs to be
  copied over from userspace;
- the second and fourth argument are passed through anyway.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2019-12-12 14:49:57 +01:00
Paulo Alcantara (SUSE) 8902dd5260 init: Support mounting root file systems over SMB
Add a new virtual device named /dev/cifs (0xfe) to tell the kernel to
mount the root file system over the network by using SMB protocol.

cifs_root_data() will be responsible to retrieve the parsed
information of the new command-line option (cifsroot=) and then call
do_mount_root() with the appropriate mount options for cifs.ko.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02 12:15:15 -04:00
David Howells f32356261d vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
Convert the ramfs, shmem, tmpfs, devtmpfs and rootfs filesystems 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.

Note that tmpfs is slightly tricky as it can contain embedded commas, so it
can't be trivially split up using strsep() to break on commas in
generic_parse_monolithic().  Instead, tmpfs has to supply its own generic
parser.

However, if tmpfs changes, then devtmpfs and rootfs, which are wrappers
around tmpfs or ramfs, must change too - and thus so must ramfs, so these
had to be converted also.

[AV: rewritten]

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hugh Dickins <hughd@google.com>
cc: linux-mm@kvack.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-12 21:05:34 -04:00
Al Viro 7e30d2a5eb make shmem_fill_super() static
... have callers use shmem_mount()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05 14:34:28 -04:00
Al Viro df02450217 make ramfs_fill_super() static
all users should just call ramfs_mount()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05 14:34:27 -04:00