<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/scsi, branch v6.1-rc4</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi</title>
<updated>2022-10-30T01:12:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-30T01:12:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=83633ed70c50d3a8470c7e40732efa165dcc2dc7'/>
<id>83633ed70c50d3a8470c7e40732efa165dcc2dc7</id>
<content type='text'>
Pull SCSI fixes from James Bottomley:
 "Varions small  fixes, all  in drivers.

  Some of these arrived during the merge window and got held over to
  make sure of testing on the -rc tree.

  The biggest change is for standards conformance in the target driver,
  closely followed by a set of bug fixes in megaraid_sas"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
  scsi: ufs: core: Fix typo in comment
  scsi: mpi3mr: Select CONFIG_SCSI_SAS_ATTRS
  scsi: ufs: core: Fix typo for register name in comments
  scsi: pm80xx: Display proc_name in sysfs
  scsi: ufs: core: Fix the error log in ufshcd_query_flag_retry()
  scsi: ufs: core: Remove unneeded casts from void *
  scsi: lpfc: Fix spelling mistake "unsolicted" -&gt; "unsolicited"
  scsi: qla2xxx: Use transport-defined speed mask for supported_speeds
  scsi: target: iblock: Fold iblock_emulate_read_cap_with_block_size() into iblock_get_blocks()
  scsi: qla2xxx: Fix serialization of DCBX TLV data request
  scsi: ufs: qcom: Remove redundant dev_err() call
  scsi: megaraid_sas: Move megasas_dbg_lvl init to megasas_init()
  scsi: megaraid_sas: Remove unnecessary memset()
  scsi: megaraid_sas: Simplify megasas_update_device_list
  scsi: megaraid_sas: Correct an error message
  scsi: megaraid_sas: Correct value passed to scsi_device_lookup()
  scsi: target: core: UA on all LUNs after reset
  scsi: target: core: New key must be used for moved PR
  scsi: target: core: Abort all preempted regs if requested
  scsi: target: core: Fix memory leak in preempt_and_abort
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull SCSI fixes from James Bottomley:
 "Varions small  fixes, all  in drivers.

  Some of these arrived during the merge window and got held over to
  make sure of testing on the -rc tree.

  The biggest change is for standards conformance in the target driver,
  closely followed by a set of bug fixes in megaraid_sas"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
  scsi: ufs: core: Fix typo in comment
  scsi: mpi3mr: Select CONFIG_SCSI_SAS_ATTRS
  scsi: ufs: core: Fix typo for register name in comments
  scsi: pm80xx: Display proc_name in sysfs
  scsi: ufs: core: Fix the error log in ufshcd_query_flag_retry()
  scsi: ufs: core: Remove unneeded casts from void *
  scsi: lpfc: Fix spelling mistake "unsolicted" -&gt; "unsolicited"
  scsi: qla2xxx: Use transport-defined speed mask for supported_speeds
  scsi: target: iblock: Fold iblock_emulate_read_cap_with_block_size() into iblock_get_blocks()
  scsi: qla2xxx: Fix serialization of DCBX TLV data request
  scsi: ufs: qcom: Remove redundant dev_err() call
  scsi: megaraid_sas: Move megasas_dbg_lvl init to megasas_init()
  scsi: megaraid_sas: Remove unnecessary memset()
  scsi: megaraid_sas: Simplify megasas_update_device_list
  scsi: megaraid_sas: Correct an error message
  scsi: megaraid_sas: Correct value passed to scsi_device_lookup()
  scsi: target: core: UA on all LUNs after reset
  scsi: target: core: New key must be used for moved PR
  scsi: target: core: Abort all preempted regs if requested
  scsi: target: core: Fix memory leak in preempt_and_abort
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: mpt3sas: re-do lost mpt3sas DMA mask fix</title>
<updated>2022-10-25T07:33:16+00:00</updated>
<author>
<name>Sreekanth Reddy</name>
<email>sreekanth.reddy@broadcom.com</email>
</author>
<published>2022-09-13T12:05:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1a2dcbdde82e3a5f1db9b2f4c48aa1aeba534fb2'/>
<id>1a2dcbdde82e3a5f1db9b2f4c48aa1aeba534fb2</id>
<content type='text'>
This is a re-do of commit e0e0747de0ea ("scsi: mpt3sas: Fix return value
check of dma_get_required_mask()"), which I ended up undoing in a
mis-merge in commit 62e6e5940c0c ("Merge tag 'scsi-misc' of
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi").

The original commit message was

  scsi: mpt3sas: Fix return value check of dma_get_required_mask()

  Fix the incorrect return value check of dma_get_required_mask().  Due to
  this incorrect check, the driver was always setting the DMA mask to 63 bit.

  Link: https://lore.kernel.org/r/20220913120538.18759-2-sreekanth.reddy@broadcom.com
  Fixes: ba27c5cf286d ("scsi: mpt3sas: Don't change the DMA coherent mask after allocations")
  Signed-off-by: Sreekanth Reddy &lt;sreekanth.reddy@broadcom.com&gt;
  Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;

and this fix was lost when I mis-merged the conflict with commit
9df650963bf6 ("scsi: mpt3sas: Don't change DMA mask while reallocating
pools").

Reported-by: Juergen Gross &lt;jgross@suse.com&gt;
Fixes: 62e6e5940c0c ("Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi")
Link: https://lore.kernel.org/all/CAHk-=wjaK-TxrNaGtFDpL9qNHL1MVkWXO1TT6vObD5tXMSC4Zg@mail.gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is a re-do of commit e0e0747de0ea ("scsi: mpt3sas: Fix return value
check of dma_get_required_mask()"), which I ended up undoing in a
mis-merge in commit 62e6e5940c0c ("Merge tag 'scsi-misc' of
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi").

The original commit message was

  scsi: mpt3sas: Fix return value check of dma_get_required_mask()

  Fix the incorrect return value check of dma_get_required_mask().  Due to
  this incorrect check, the driver was always setting the DMA mask to 63 bit.

  Link: https://lore.kernel.org/r/20220913120538.18759-2-sreekanth.reddy@broadcom.com
  Fixes: ba27c5cf286d ("scsi: mpt3sas: Don't change the DMA coherent mask after allocations")
  Signed-off-by: Sreekanth Reddy &lt;sreekanth.reddy@broadcom.com&gt;
  Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;

and this fix was lost when I mis-merged the conflict with commit
9df650963bf6 ("scsi: mpt3sas: Don't change DMA mask while reallocating
pools").

Reported-by: Juergen Gross &lt;jgross@suse.com&gt;
Fixes: 62e6e5940c0c ("Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi")
Link: https://lore.kernel.org/all/CAHk-=wjaK-TxrNaGtFDpL9qNHL1MVkWXO1TT6vObD5tXMSC4Zg@mail.gmail.com
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: mpi3mr: Select CONFIG_SCSI_SAS_ATTRS</title>
<updated>2022-10-22T03:14:51+00:00</updated>
<author>
<name>Michal Kubecek</name>
<email>mkubecek@suse.cz</email>
</author>
<published>2022-10-17T14:55:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=65244389b1b347447a7eed866d9d458963e851e8'/>
<id>65244389b1b347447a7eed866d9d458963e851e8</id>
<content type='text'>
Starting with commit 42fc9fee116f ("scsi: mpi3mr: Add helper functions to
manage device's port"), kernel configured with CONFIG_SCSI_MPI3MR=m and
CONFIG_SCSI_SAS_ATTRS=n fails to build because modpost cannot find symbols
used in mpi3mr_transport.c:

  ERROR: modpost: "sas_port_alloc_num" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_remove_host" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_phy_alloc" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_phy_free" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ...

Select CONFIG_SCSI_SAS_ATTRS when CONFIG_SCSI_MPI3MR is enabled to prevent
inconsistent configs.

Link: https://lore.kernel.org/r/20221017145517.93BCB6043B@lion.mk-sys.cz
Fixes: 42fc9fee116f ("scsi: mpi3mr: Add helper functions to manage device's port")
Acked-by: Sathya Prakash Veerichetty &lt;sathya.prakash@broadcom.com&gt;
Signed-off-by: Michal Kubecek &lt;mkubecek@suse.cz&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Starting with commit 42fc9fee116f ("scsi: mpi3mr: Add helper functions to
manage device's port"), kernel configured with CONFIG_SCSI_MPI3MR=m and
CONFIG_SCSI_SAS_ATTRS=n fails to build because modpost cannot find symbols
used in mpi3mr_transport.c:

  ERROR: modpost: "sas_port_alloc_num" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_remove_host" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_phy_alloc" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ERROR: modpost: "sas_phy_free" [drivers/scsi/mpi3mr/mpi3mr.ko] undefined!
  ...

Select CONFIG_SCSI_SAS_ATTRS when CONFIG_SCSI_MPI3MR is enabled to prevent
inconsistent configs.

Link: https://lore.kernel.org/r/20221017145517.93BCB6043B@lion.mk-sys.cz
Fixes: 42fc9fee116f ("scsi: mpi3mr: Add helper functions to manage device's port")
Acked-by: Sathya Prakash Veerichetty &lt;sathya.prakash@broadcom.com&gt;
Signed-off-by: Michal Kubecek &lt;mkubecek@suse.cz&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: pm80xx: Display proc_name in sysfs</title>
<updated>2022-10-22T03:05:52+00:00</updated>
<author>
<name>Igor Pylypiv</name>
<email>ipylypiv@google.com</email>
</author>
<published>2022-10-07T23:06:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=181dfce9b63b80adbb861b219550ec9b27fe63d5'/>
<id>181dfce9b63b80adbb861b219550ec9b27fe63d5</id>
<content type='text'>
The proc_name entry in sysfs for pm80xx is "(null)" because it is not
initialized in scsi_host_template:

Before:
host:~# cat /sys/class/scsi_host/host6/proc_name
(null)

After:
host:~# cat /sys/class/scsi_host/host6/proc_name
pm80xx

Signed-off-by: Igor Pylypiv &lt;ipylypiv@google.com&gt;
Link: https://lore.kernel.org/r/20221007230651.308969-1-ipylypiv@google.com
Reviewed-by: Jolly Shah &lt;jollys@google.com&gt;
Acked-by: Jack Wang &lt;jinpu.wang@ionos.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The proc_name entry in sysfs for pm80xx is "(null)" because it is not
initialized in scsi_host_template:

Before:
host:~# cat /sys/class/scsi_host/host6/proc_name
(null)

After:
host:~# cat /sys/class/scsi_host/host6/proc_name
pm80xx

Signed-off-by: Igor Pylypiv &lt;ipylypiv@google.com&gt;
Link: https://lore.kernel.org/r/20221007230651.308969-1-ipylypiv@google.com
Reviewed-by: Jolly Shah &lt;jollys@google.com&gt;
Acked-by: Jack Wang &lt;jinpu.wang@ionos.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch '6.1/scsi-queue' into 6.1/scsi-fixes</title>
<updated>2022-10-21T01:10:34+00:00</updated>
<author>
<name>Martin K. Petersen</name>
<email>martin.petersen@oracle.com</email>
</author>
<published>2022-10-21T01:10:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=47eee861fa91b308800968d988975f4b9de54458'/>
<id>47eee861fa91b308800968d988975f4b9de54458</id>
<content type='text'>
Include the patches that weren't included in the 6.1 pull request.

Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Include the patches that weren't included in the 6.1 pull request.

Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: lpfc: Fix memory leak in lpfc_create_port()</title>
<updated>2022-10-18T02:42:08+00:00</updated>
<author>
<name>Rafael Mendonca</name>
<email>rafaelmendsr@gmail.com</email>
</author>
<published>2022-09-16T03:59:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dc8e483f684a24cc06e1d5fa958b54db58855093'/>
<id>dc8e483f684a24cc06e1d5fa958b54db58855093</id>
<content type='text'>
Commit 5e633302ace1 ("scsi: lpfc: vmid: Add support for VMID in mailbox
command") introduced allocations for the VMID resources in
lpfc_create_port() after the call to scsi_host_alloc(). Upon failure on the
VMID allocations, the new code would branch to the 'out' label, which
returns NULL without unwinding anything, thus skipping the call to
scsi_host_put().

Fix the problem by creating a separate label 'out_free_vmid' to unwind the
VMID resources and make the 'out_put_shost' label call only
scsi_host_put(), as was done before the introduction of allocations for
VMID.

Fixes: 5e633302ace1 ("scsi: lpfc: vmid: Add support for VMID in mailbox command")
Signed-off-by: Rafael Mendonca &lt;rafaelmendsr@gmail.com&gt;
Link: https://lore.kernel.org/r/20220916035908.712799-1-rafaelmendsr@gmail.com
Reviewed-by: James Smart &lt;jsmart2021@gmail.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 5e633302ace1 ("scsi: lpfc: vmid: Add support for VMID in mailbox
command") introduced allocations for the VMID resources in
lpfc_create_port() after the call to scsi_host_alloc(). Upon failure on the
VMID allocations, the new code would branch to the 'out' label, which
returns NULL without unwinding anything, thus skipping the call to
scsi_host_put().

Fix the problem by creating a separate label 'out_free_vmid' to unwind the
VMID resources and make the 'out_put_shost' label call only
scsi_host_put(), as was done before the introduction of allocations for
VMID.

Fixes: 5e633302ace1 ("scsi: lpfc: vmid: Add support for VMID in mailbox command")
Signed-off-by: Rafael Mendonca &lt;rafaelmendsr@gmail.com&gt;
Link: https://lore.kernel.org/r/20220916035908.712799-1-rafaelmendsr@gmail.com
Reviewed-by: James Smart &lt;jsmart2021@gmail.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: core: Restrict legal sdev_state transitions via sysfs</title>
<updated>2022-10-18T02:26:29+00:00</updated>
<author>
<name>Uday Shankar</name>
<email>ushankar@purestorage.com</email>
</author>
<published>2022-09-24T00:02:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2331ce6126be8864b39490e705286b66e2344aac'/>
<id>2331ce6126be8864b39490e705286b66e2344aac</id>
<content type='text'>
Userspace can currently write to sysfs to transition sdev_state to RUNNING
or OFFLINE from any source state. This causes issues because proper
transitioning out of some states involves steps besides just changing
sdev_state, so allowing userspace to change sdev_state regardless of the
source state can result in inconsistencies; e.g. with ISCSI we can end up
with sdev_state == SDEV_RUNNING while the device queue is quiesced. Any
task attempting I/O on the device will then hang, and in more recent
kernels, iscsid will hang as well.

More detail about this bug is provided in my first attempt:

https://groups.google.com/g/open-iscsi/c/PNKca4HgPDs/m/CXaDkntOAQAJ

Link: https://lore.kernel.org/r/20220924000241.2967323-1-ushankar@purestorage.com
Signed-off-by: Uday Shankar &lt;ushankar@purestorage.com&gt;
Suggested-by: Mike Christie &lt;michael.christie@oracle.com&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Userspace can currently write to sysfs to transition sdev_state to RUNNING
or OFFLINE from any source state. This causes issues because proper
transitioning out of some states involves steps besides just changing
sdev_state, so allowing userspace to change sdev_state regardless of the
source state can result in inconsistencies; e.g. with ISCSI we can end up
with sdev_state == SDEV_RUNNING while the device queue is quiesced. Any
task attempting I/O on the device will then hang, and in more recent
kernels, iscsid will hang as well.

More detail about this bug is provided in my first attempt:

https://groups.google.com/g/open-iscsi/c/PNKca4HgPDs/m/CXaDkntOAQAJ

Link: https://lore.kernel.org/r/20220924000241.2967323-1-ushankar@purestorage.com
Signed-off-by: Uday Shankar &lt;ushankar@purestorage.com&gt;
Suggested-by: Mike Christie &lt;michael.christie@oracle.com&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: use get_random_u32() when possible</title>
<updated>2022-10-11T23:42:58+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T15:43:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a251c17aa558d8e3128a528af5cf8b9d7caae4fd'/>
<id>a251c17aa558d8e3128a528af5cf8b9d7caae4fd</id>
<content type='text'>
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Acked-by: Chuck Lever &lt;chuck.lever@oracle.com&gt; # for nfsd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt; # for thunderbolt
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Acked-by: Helge Deller &lt;deller@gmx.de&gt; # for parisc
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Acked-by: Chuck Lever &lt;chuck.lever@oracle.com&gt; # for nfsd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt; # for thunderbolt
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Acked-by: Helge Deller &lt;deller@gmx.de&gt; # for parisc
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: use get_random_{u8,u16}() when possible, part 1</title>
<updated>2022-10-11T23:42:58+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T15:23:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7e3cf0843fe505491baa05e355e83e6997e089dd'/>
<id>7e3cf0843fe505491baa05e355e83e6997e089dd</id>
<content type='text'>
Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster than
wasting the additional bytes from a 32-bit value. This was done
mechanically with this coccinelle script:

@@
expression E;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
typedef __be16;
typedef __le16;
typedef u8;
@@
(
- (get_random_u32() &amp; 0xffff)
+ get_random_u16()
|
- (get_random_u32() &amp; 0xff)
+ get_random_u8()
|
- (get_random_u32() % 65536)
+ get_random_u16()
|
- (get_random_u32() % 256)
+ get_random_u8()
|
- (get_random_u32() &gt;&gt; 16)
+ get_random_u16()
|
- (get_random_u32() &gt;&gt; 24)
+ get_random_u8()
|
- (u16)get_random_u32()
+ get_random_u16()
|
- (u8)get_random_u32()
+ get_random_u8()
|
- (__be16)get_random_u32()
+ (__be16)get_random_u16()
|
- (__le16)get_random_u32()
+ (__le16)get_random_u16()
|
- prandom_u32_max(65536)
+ get_random_u16()
|
- prandom_u32_max(256)
+ get_random_u8()
|
- E-&gt;inet_id = get_random_u32()
+ E-&gt;inet_id = get_random_u16()
)

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
identifier v;
@@
- u16 v = get_random_u32();
+ u16 v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
identifier v;
@@
- u8 v = get_random_u32();
+ u8 v = get_random_u8();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
u16 v;
@@
-  v = get_random_u32();
+  v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
u8 v;
@@
-  v = get_random_u32();
+  v = get_random_u8();

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Examine limits
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value &lt; 256:
        coccinelle.RESULT = cocci.make_ident("get_random_u8")
elif value &lt; 65536:
        coccinelle.RESULT = cocci.make_ident("get_random_u16")
else:
        print("Skipping large mask of %s" % (literal))
        cocci.include_match(False)

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
identifier add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       (RESULT() &amp; LITERAL)

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster than
wasting the additional bytes from a 32-bit value. This was done
mechanically with this coccinelle script:

@@
expression E;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
typedef __be16;
typedef __le16;
typedef u8;
@@
(
- (get_random_u32() &amp; 0xffff)
+ get_random_u16()
|
- (get_random_u32() &amp; 0xff)
+ get_random_u8()
|
- (get_random_u32() % 65536)
+ get_random_u16()
|
- (get_random_u32() % 256)
+ get_random_u8()
|
- (get_random_u32() &gt;&gt; 16)
+ get_random_u16()
|
- (get_random_u32() &gt;&gt; 24)
+ get_random_u8()
|
- (u16)get_random_u32()
+ get_random_u16()
|
- (u8)get_random_u32()
+ get_random_u8()
|
- (__be16)get_random_u32()
+ (__be16)get_random_u16()
|
- (__le16)get_random_u32()
+ (__le16)get_random_u16()
|
- prandom_u32_max(65536)
+ get_random_u16()
|
- prandom_u32_max(256)
+ get_random_u8()
|
- E-&gt;inet_id = get_random_u32()
+ E-&gt;inet_id = get_random_u16()
)

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
identifier v;
@@
- u16 v = get_random_u32();
+ u16 v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
identifier v;
@@
- u8 v = get_random_u32();
+ u8 v = get_random_u8();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
u16 v;
@@
-  v = get_random_u32();
+  v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
u8 v;
@@
-  v = get_random_u32();
+  v = get_random_u8();

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Examine limits
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value &lt; 256:
        coccinelle.RESULT = cocci.make_ident("get_random_u8")
elif value &lt; 65536:
        coccinelle.RESULT = cocci.make_ident("get_random_u16")
else:
        print("Skipping large mask of %s" % (literal))
        cocci.include_match(False)

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
identifier add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       (RESULT() &amp; LITERAL)

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: use prandom_u32_max() when possible, part 1</title>
<updated>2022-10-11T23:42:55+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T14:43:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=81895a65ec63ee1daec3255dc1a06675d2fbe915'/>
<id>81895a65ec63ee1daec3255dc1a06675d2fbe915</id>
<content type='text'>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
