Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
接近 2 年 前同步成功

通知 170
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 22 2月, 2012 1 次提交
    • H
      asm-generic: architecture independent readq/writeq for 32bit environment · 797a796a
      由 Hitoshi Mitake 提交于 
      This provides unified readq()/writeq() helper functions for 32-bit
drivers.

For some cases, readq/writeq without atomicity is harmful, and order of
io access has to be specified explicitly.  So in this patch, new two
header files which contain non-atomic readq/writeq are added.

 - <asm-generic/io-64-nonatomic-lo-hi.h> provides non-atomic readq/
   writeq with the order of lower address -> higher address

 - <asm-generic/io-64-nonatomic-hi-lo.h> provides non-atomic readq/
   writeq with reversed order

This allows us to remove some readq()s that were added drivers when the
default non-atomic ones were removed in commit dbee8a0a ("x86:
remove 32-bit versions of readq()/writeq()")

The drivers which need readq/writeq but can do with the non-atomic ones
must add the line:

  #include <asm-generic/io-64-nonatomic-lo-hi.h> /* or hi-lo.h */

But this will be nop in 64-bit environments, and no other #ifdefs are
required.  So I believe that this patch can solve the problem of
 1. driver-specific readq/writeq
 2. atomicity and order of io access

This patch is tested with building allyesconfig and allmodconfig as
ARCH=x86 and ARCH=i386 on top of tip/master.

Cc: Kashyap Desai <Kashyap.Desai@lsi.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Ravi Anand <ravi.anand@qlogic.com>
Cc: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Jason Uhlenkott <juhlenko@akamai.com>
Cc: James Bottomley <James.Bottomley@parallels.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: James Bottomley <jbottomley@parallels.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NHitoshi Mitake <h.mitake@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      797a796a
  3. 22 1月, 2012 2 次提交
  5. 16 1月, 2012 34 次提交
  7. 15 1月, 2012 2 次提交
    • P
      block: fail SCSI passthrough ioctls on partition devices · 0bfc96cb
      由 Paolo Bonzini 提交于 
      Linux allows executing the SG_IO ioctl on a partition or LVM volume, and
will pass the command to the underlying block device.  This is
well-known, but it is also a large security problem when (via Unix
permissions, ACLs, SELinux or a combination thereof) a program or user
needs to be granted access only to part of the disk.

This patch lets partitions forward a small set of harmless ioctls;
others are logged with printk so that we can see which ioctls are
actually sent.  In my tests only CDROM_GET_CAPABILITY actually occurred.
Of course it was being sent to a (partition on a) hard disk, so it would
have failed with ENOTTY and the patch isn't changing anything in
practice.  Still, I'm treating it specially to avoid spamming the logs.

In principle, this restriction should include programs running with
CAP_SYS_RAWIO.  If for example I let a program access /dev/sda2 and
/dev/sdb, it still should not be able to read/write outside the
boundaries of /dev/sda2 independent of the capabilities.  However, for
now programs with CAP_SYS_RAWIO will still be allowed to send the
ioctls.  Their actions will still be logged.

This patch does not affect the non-libata IDE driver.  That driver
however already tests for bd != bd->bd_contains before issuing some
ioctl; it could be restricted further to forbid these ioctls even for
programs running with CAP_SYS_ADMIN/CAP_SYS_RAWIO.

Cc: linux-scsi@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: James Bottomley <JBottomley@parallels.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
[ Make it also print the command name when warning - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0bfc96cb
    • P
      block: add and use scsi_blk_cmd_ioctl · 577ebb37
      由 Paolo Bonzini 提交于 
      Introduce a wrapper around scsi_cmd_ioctl that takes a block device.

The function will then be enhanced to detect partition block devices
and, in that case, subject the ioctls to whitelisting.

Cc: linux-scsi@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: James Bottomley <JBottomley@parallels.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      577ebb37
  9. 13 1月, 2012 1 次提交