linux-stable.git/init/initramfs.c, branch v4.13.2

initramfs: use vfs_stat/lstat directly

2017-05-09T00:15:12+00:00

sys_newlstat is a system call implementation that is meant for user
space, and that copies kernel-internal data structure to the user
format, which is not needed for in-kernel users.

Further, as we rearrange the system call implementation so we can extend
it with 64-bit time_t, the prototype for sys_newlstat changes.

This changes the initramfs code to use vfs_lstat directly, to get it out
of the way of the time_t changes, and make it slightly more efficient in
the process.  Along the same lines we also replace sys_stat and
sys_stat64 with vfs_stat.

Link: http://lkml.kernel.org/r/20170314214932.4052842-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann 
Cc: Alexander Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: provide a way to ignore image provided by bootloader

2017-05-09T00:15:12+00:00

Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel
to override the command line provided by an inflexible bootloader.
However there is currrently no way for the kernel to override the
initramfs image provided by the bootloader meaning there are still ways
for bootloaders to make things difficult for us.

Fix this by introducing INITRAMFS_FORCE which can prevent the kernel
from loading the bootloader supplied image.

We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the
system has an inflexible bootloader.  This allow us to avoid presenting
this config option to users of systems where inflexible bootloaders
aren't usually a problem.

Link: http://lkml.kernel.org/r/20170217121940.30126-1-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: avoid "label at end of compound statement" error

2017-05-06T17:27:13+00:00

Commit 17a9be317475 ("initramfs: Always do fput() and load modules after
rootfs populate") introduced an error for the

    CONFIG_BLK_DEV_RAM=y

case, because even though the code looks fine, the compiler really wants
a statement after a label, or you'll get complaints:

  init/initramfs.c: In function 'populate_rootfs':
  init/initramfs.c:644:2: error: label at end of compound statement

That commit moved the subsequent statements to outside the compound
statement, leaving the label without any associated statements.

Reported-by: Jörg Otte 
Fixes: 17a9be317475 ("initramfs: Always do fput() and load modules after rootfs populate")
Cc: Al Viro 
Cc: Stafford Horne 
Cc: stable@vger.kernel.org  # if 17a9be317475 gets backported
Signed-off-by: Linus Torvalds

initramfs: Always do fput() and load modules after rootfs populate

2017-05-05T07:01:08+00:00

In OpenRISC we do not have a bootloader passed initrd, but the built in
initramfs does contain the /init and other binaries, including modules.
The previous commit 08865514805d2 ("initramfs: finish fput() before
accessing any binary from initramfs") made a change to only call fput()
if the bootloader initrd was available, this caused intermittent crashes
for OpenRISC.

This patch changes the fput() to happen unconditionally if any rootfs is
loaded. Also, I added some comments to make it a bit more clear why we
call unpack_to_rootfs() multiple times.

Fixes: 08865514805d2 ("initramfs: finish fput() before accessing any binary from initramfs")
Cc: stable@vger.kernel.org
Cc: Lokesh Vutla 
Cc: Al Viro 
Acked-by: Al Viro 
Signed-off-by: Stafford Horne

initramfs: finish fput() before accessing any binary from initramfs

2017-02-28T02:43:46+00:00

Commit 4a9d4b024a31 ("switch fput to task_work_add") implements a
schedule_work() for completing fput(), but did not guarantee calling
__fput() after unpacking initramfs.  Because of this, there is a
possibility that during boot a driver can see ETXTBSY when it tries to
load a binary from initramfs as fput() is still pending on that binary.

This patch makes sure that fput() is completed after unpacking initramfs
and removes the call to flush_delayed_fput() in kernel_init() which
happens very late after unpacking initramfs.

Link: http://lkml.kernel.org/r/20170201140540.22051-1-lokeshvutla@ti.com
Signed-off-by: Lokesh Vutla 
Reported-by: Murali Karicheri 
Cc: Al Viro 
Cc: Tero Kristo 
Cc: Sekhar Nori 
Cc: Nishanth Menon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: split kexec_load syscall from kexec core code

2015-09-10T20:29:01+00:00

There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young 
Cc: Eric W. Biederman 
Cc: Vivek Goyal 
Cc: Petr Tesarik 
Cc: Theodore Ts'o 
Cc: Josh Boyer 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

init/initramfs.c: resolve shadow warnings

2014-10-14T00:18:22+00:00

Resolve shadow warnings that are produced in W=2 builds by renaming a
global with a too-generic name and renaming a formal parameter.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mark Rustad 
Signed-off-by: Jeff Kirsher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: add write error checks

2014-08-08T22:57:26+00:00

On a system with low memory extracting the initramfs may fail.  If this
happens the user gets "Failed to execute /init" instead of an initramfs
error.

Check return value of sys_write and call error() when the write was
incomplete or failed.

Signed-off-by: David Engraf 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: support initramfs that is bigger than 2GiB

2014-08-08T22:57:26+00:00

Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.

Found compressed initramfs image could not be decompressed properly.  It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G.  Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.

Change len to long, that should be ok as on 32 bit platform long is
32bits.

Tested with following compressed initramfs image as root with kexec.
	gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
   size        name       Nehalem-EX  Westmere-EX  Ivybridge-EX
 9034400256 root_img     :   26s           24s          30s
 3561095057 root_img.lz4 :   28s           27s          27s
 3459554629 root_img.lzo :   29s           29s          28s
 3219399480 root_img.gz  :   64s           62s          49s
 2251594592 root_img.xz  :  262s          260s         183s
 2226366598 root_img.lzma:  386s          376s         277s
 2901482513 root_img.bz2 :  635s          599s

Signed-off-by: Yinghai Lu 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Rashika Kheria 
Cc: Josh Triplett 
Cc: Kyungsik Lee 
Cc: P J P 
Cc: Al Viro 
Cc: Tetsuo Handa 
Cc: "Daniel M. Weeks" 
Cc: Alexandre Courbot 
Cc: Jan Beulich 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: support initrd that is bigger than 2GiB

2014-08-08T22:57:26+00:00

When initrd (compressed or not) is used, kernel report data corrupted with
/dev/ram0.

The root cause:
During initramfs checking, if it is initrd, it will be transferred to
/initrd.image with sys_write.
sys_write only support 2G-4K write, so if the initrd ram is more than
that, /initrd.image will not complete at all.

Add local xwrite to loop calling sys_write to workaround the problem.

Also need to use xwrite in write_buffer() to handle:
image is uncompressed cpio and there is one big file (>2G) in it.
   unpack_to_rootfs ===> write_buffer ===> actions[]/do_copy

At the same time, we don't need to worry about sys_read/sys_write in
do_mounts_rd.c::crd_load.  As decompressor will have fill/flush and local
buffer that is smaller than 2G.

Test with uncompressed initrd, and compressed ones with gz, bz2, lzma,xz,
lzop.

Signed-off-by: Yinghai Lu 
Acked-by: H. Peter Anvin 
Cc: Ingo Molnar 
Cc: Geert Uytterhoeven 
Cc: Tetsuo Handa 
Cc: "Daniel M. Weeks" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds