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Damien Le Moal e15de347fa scsi: core: Fix scsi_mode_sense() buffer length handling
[ Upstream commit 17b49bcbf8 ]

Several problems exist with scsi_mode_sense() buffer length handling:

 1) The allocation length field of the MODE SENSE(10) command is 16-bits,
    occupying bytes 7 and 8 of the CDB. With this command, access to mode
    pages larger than 255 bytes is thus possible. However, the CDB
    allocation length field is set by assigning len to byte 8 only, thus
    truncating buffer length larger than 255.

 2) If scsi_mode_sense() is called with len smaller than 8 with
    sdev->use_10_for_ms set, or smaller than 4 otherwise, the buffer length
    is increased to 8 and 4 respectively, and the buffer is zero filled
    with these increased values, thus corrupting the memory following the
    buffer.

Fix these 2 problems by using put_unaligned_be16() to set the allocation
length field of MODE SENSE(10) CDB and by returning an error when len is
too small.

Furthermore, if len is larger than 255B, always try MODE SENSE(10) first,
even if the device driver did not set sdev->use_10_for_ms. In case of
invalid opcode error for MODE SENSE(10), access to mode pages larger than
255 bytes are not retried using MODE SENSE(6). To avoid buffer length
overflows for the MODE_SENSE(10) case, check that len is smaller than 65535
bytes.

While at it, also fix the folowing:

 * Use get_unaligned_be16() to retrieve the mode data length and block
   descriptor length fields of the mode sense reply header instead of using
   an open coded calculation.

 * Fix the kdoc dbd argument explanation: the DBD bit stands for Disable
   Block Descriptor, which is the opposite of what the dbd argument
   description was.

Link: https://lore.kernel.org/r/20210820070255.682775-2-damien.lemoal@wdc.com
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-25 09:48:26 +01:00
arch arm64: dts: ls1012a: Add serial alias for ls1012a-rdb 2021-11-25 09:48:26 +01:00
block block: Hold invalidate_lock in BLKRESETZONE ioctl 2021-11-18 19:17:15 +01:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: pcrypt - Delay write to padata->info 2021-11-18 19:16:44 +01:00
Documentation fscrypt: allow 256-bit master keys with AES-256-XTS 2021-11-18 19:16:11 +01:00
drivers scsi: core: Fix scsi_mode_sense() buffer length handling 2021-11-25 09:48:26 +01:00
fs btrfs: zoned: allow preallocation for relocation inodes 2021-11-21 13:44:13 +01:00
include bus: ti-sysc: Add quirk handling for reinit on context lost 2021-11-25 09:48:24 +01:00
init init: make unknown command line param message clearer 2021-11-18 19:17:11 +01:00
ipc ipc: remove memcg accounting for sops objects in do_semtimedop() 2021-09-14 10:22:11 -07:00
kernel perf/core: Avoid put_page() when GUP fails 2021-11-21 13:44:14 +01:00
lib string: uninline memcpy_and_pad 2021-11-21 13:44:12 +01:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm, oom: do not trigger out_of_memory from the #PF 2021-11-18 19:17:16 +01:00
net SUNRPC: Partial revert of commit 6f9f17287e 2021-11-18 19:17:20 +01:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-18 19:16:42 +01:00
scripts leaking_addresses: Always print a trailing newline 2021-11-18 19:16:16 +01:00
security fortify: Explicitly disable Clang support 2021-11-21 13:44:13 +01:00
sound ASoC: SOF: Intel: hda-dai: fix potential locking issue 2021-11-25 09:48:26 +01:00
tools selftests/bpf: Fix also no-alu32 strobemeta selftest 2021-11-18 19:17:21 +01:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Remove tlbs_dirty 2021-09-23 11:01:12 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.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 mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 drm fixes for 5.15 final 2021-10-28 12:17:01 -07:00
Makefile Linux 5.15.4 2021-11-21 13:44:15 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.