Go to file
Bart Van Assche 6418074260 scsi: ufs: Fix the SCSI abort handler
Make the following changes in ufshcd_abort():

 - Return FAILED instead of SUCCESS if the abort handler notices that a
   SCSI command has already been completed. Returning SUCCESS in this case
   triggers a use-after-free and may trigger a kernel crash.

 - Fix the code for aborting SCSI commands submitted to a WLUN.

The current approach for aborting SCSI commands that have been submitted to
a WLUN and that timed out is as follows:

 - Report to the SCSI core that the command has completed successfully.
   Let the block layer free any data buffers associated with the command.

 - Mark the command as outstanding in 'outstanding_reqs'.

 - If the block layer tries to reuse the tag associated with the aborted
   command, busy-wait until the tag is freed.

This approach can result in:

 - Memory corruption if the controller accesses the data buffer after the
   block layer has freed the associated data buffers.

 - A race condition if ufshcd_queuecommand() or ufshcd_exec_dev_cmd()
   checks the bit that corresponds to an aborted command in
   'outstanding_reqs' after it has been cleared and before it is reset.

 - High energy consumption if ufshcd_queuecommand() repeatedly returns
   SCSI_MLQUEUE_HOST_BUSY.

Fix this by reporting to the SCSI error handler that aborting a SCSI
command failed if the SCSI command was submitted to a WLUN.

Link: https://lore.kernel.org/r/20210722033439.26550-15-bvanassche@acm.org
Fixes: 7a7e66c65d ("scsi: ufs: Fix a race condition between ufshcd_abort() and eh_work()")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Can Guo <cang@codeaurora.org>
Cc: Asutosh Das <asutoshd@codeaurora.org>
Cc: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-08-02 21:43:59 -04:00
Documentation scsi: ufs: ufshpb: Make host mode parameters configurable 2021-08-01 16:05:15 -04:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
arch ARM: SoC fixes for v5.14 2021-07-17 15:58:24 -07:00
block scsi: bsg-lib: Fix commands without data transfer in bsg_transport_sg_io_fn() 2021-08-01 13:21:40 -04:00
certs Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-07-09 11:00:44 -07:00
drivers scsi: ufs: Fix the SCSI abort handler 2021-08-02 21:43:59 -04:00
fs scsi: core: Rename CONFIG_BLK_SCSI_REQUEST to CONFIG_SCSI_COMMON 2021-07-28 22:24:27 -04:00
include scsi: bsg: Move the whole request execution into the SCSI/transport handlers 2021-07-30 22:22:36 -04:00
init Revert "mm/slub: use stackdepot to save stack trace in objects" 2021-07-17 13:27:00 -07:00
ipc Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
kernel tracing: Fix the histogram logic from possibly crashing the kernel 2021-07-17 12:36:51 -07:00
lib lib/test_hmm: remove set but unused page variable 2021-07-15 10:13:49 -07:00
mm Revert "mm/slub: use stackdepot to save stack trace in objects" 2021-07-17 13:27:00 -07:00
net Networking fixes for 5.14-rc2, including fixes from bpf and netfilter. 2021-07-14 09:24:32 -07:00
samples Networking fixes for 5.14-rc2, including fixes from bpf and netfilter. 2021-07-14 09:24:32 -07:00
scripts Kbuild fixes for v5.14 2021-07-18 11:10:30 -07:00
security asm-generic/unaligned: Unify asm/unaligned.h around struct helper 2021-07-02 12:43:40 -07:00
sound ASoC: Mediatek: MT8183: Fix fall-through warning for Clang 2021-07-13 14:58:18 -05:00
tools perf tools fixes for v5.14: 1st batch 2021-07-18 12:20:27 -07:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt * Allow again loading KVM on 32-bit non-PAE builds 2021-07-15 11:56:07 -07:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap m68k updates for v5.14 2021-06-28 14:01:03 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS IOMMU Fixes for Linux v5.14-rc1 2021-07-15 11:50:15 -07:00
Makefile Linux 5.14-rc2 2021-07-18 14:13:49 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.