<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/char, branch v5.16.3</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tpm: fix NPE on probe for missing device</title>
<updated>2022-01-27T11:02:43+00:00</updated>
<author>
<name>Patrick Williams</name>
<email>patrick@stwcx.xyz</email>
</author>
<published>2021-12-23T15:49:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=13fe4bdb76ca9ec1e441e6292220dbd55fef07cc'/>
<id>13fe4bdb76ca9ec1e441e6292220dbd55fef07cc</id>
<content type='text'>
commit 84cc69589700b90a4c8d27b481a51fce8cca6051 upstream.

When using the tpm_tis-spi driver on a system missing the physical TPM,
a null pointer exception was observed.

    [    0.938677] Unable to handle kernel NULL pointer dereference at virtual address 00000004
    [    0.939020] pgd = 10c753cb
    [    0.939237] [00000004] *pgd=00000000
    [    0.939808] Internal error: Oops: 5 [#1] SMP ARM
    [    0.940157] CPU: 0 PID: 48 Comm: kworker/u4:1 Not tainted 5.15.10-dd1e40c #1
    [    0.940364] Hardware name: Generic DT based system
    [    0.940601] Workqueue: events_unbound async_run_entry_fn
    [    0.941048] PC is at tpm_tis_remove+0x28/0xb4
    [    0.941196] LR is at tpm_tis_core_init+0x170/0x6ac

This is due to an attempt in 'tpm_tis_remove' to use the drvdata, which
was not initialized in 'tpm_tis_core_init' prior to the first error.

Move the initialization of drvdata earlier so 'tpm_tis_remove' has
access to it.

Signed-off-by: Patrick Williams &lt;patrick@stwcx.xyz&gt;
Fixes: 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent queries")
Cc: stable@vger.kernel.org
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 84cc69589700b90a4c8d27b481a51fce8cca6051 upstream.

When using the tpm_tis-spi driver on a system missing the physical TPM,
a null pointer exception was observed.

    [    0.938677] Unable to handle kernel NULL pointer dereference at virtual address 00000004
    [    0.939020] pgd = 10c753cb
    [    0.939237] [00000004] *pgd=00000000
    [    0.939808] Internal error: Oops: 5 [#1] SMP ARM
    [    0.940157] CPU: 0 PID: 48 Comm: kworker/u4:1 Not tainted 5.15.10-dd1e40c #1
    [    0.940364] Hardware name: Generic DT based system
    [    0.940601] Workqueue: events_unbound async_run_entry_fn
    [    0.941048] PC is at tpm_tis_remove+0x28/0xb4
    [    0.941196] LR is at tpm_tis_core_init+0x170/0x6ac

This is due to an attempt in 'tpm_tis_remove' to use the drvdata, which
was not initialized in 'tpm_tis_core_init' prior to the first error.

Move the initialization of drvdata earlier so 'tpm_tis_remove' has
access to it.

Signed-off-by: Patrick Williams &lt;patrick@stwcx.xyz&gt;
Fixes: 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent queries")
Cc: stable@vger.kernel.org
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: fix potential NULL pointer access in tpm_del_char_device</title>
<updated>2022-01-27T11:02:43+00:00</updated>
<author>
<name>Lino Sanfilippo</name>
<email>LinoSanfilippo@gmx.de</email>
</author>
<published>2021-12-20T15:06:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b66371ef99a064412478909098576fbc0b37dc4a'/>
<id>b66371ef99a064412478909098576fbc0b37dc4a</id>
<content type='text'>
commit eabad7ba2c752392ae50f24a795093fb115b686d upstream.

Some SPI controller drivers unregister the controller in the shutdown
handler (e.g. BCM2835). If such a controller is used with a TPM 2 slave
chip-&gt;ops may be accessed when it is already NULL:

At system shutdown the pre-shutdown handler tpm_class_shutdown() shuts down
TPM 2 and sets chip-&gt;ops to NULL. Then at SPI controller unregistration
tpm_tis_spi_remove() is called and eventually calls tpm_del_char_device()
which tries to shut down TPM 2 again. Thereby it accesses chip-&gt;ops again:
(tpm_del_char_device calls tpm_chip_start which calls tpm_clk_enable which
calls chip-&gt;ops-&gt;clk_enable).

Avoid the NULL pointer access by testing if chip-&gt;ops is valid and skipping
the TPM 2 shutdown procedure in case it is NULL.

Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo &lt;LinoSanfilippo@gmx.de&gt;
Fixes: 39d0099f9439 ("powerpc/pseries: Add shutdown() to vio_driver and vio_bus")
Reviewed-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Tested-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit eabad7ba2c752392ae50f24a795093fb115b686d upstream.

Some SPI controller drivers unregister the controller in the shutdown
handler (e.g. BCM2835). If such a controller is used with a TPM 2 slave
chip-&gt;ops may be accessed when it is already NULL:

At system shutdown the pre-shutdown handler tpm_class_shutdown() shuts down
TPM 2 and sets chip-&gt;ops to NULL. Then at SPI controller unregistration
tpm_tis_spi_remove() is called and eventually calls tpm_del_char_device()
which tries to shut down TPM 2 again. Thereby it accesses chip-&gt;ops again:
(tpm_del_char_device calls tpm_chip_start which calls tpm_clk_enable which
calls chip-&gt;ops-&gt;clk_enable).

Avoid the NULL pointer access by testing if chip-&gt;ops is valid and skipping
the TPM 2 shutdown procedure in case it is NULL.

Cc: stable@vger.kernel.org
Signed-off-by: Lino Sanfilippo &lt;LinoSanfilippo@gmx.de&gt;
Fixes: 39d0099f9439 ("powerpc/pseries: Add shutdown() to vio_driver and vio_bus")
Reviewed-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Tested-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>random: do not throw away excess input to crng_fast_load</title>
<updated>2022-01-27T11:02:31+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2021-12-29T21:10:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6f60df29fe0379b80ddcba7bc6991b36451d9d69'/>
<id>6f60df29fe0379b80ddcba7bc6991b36451d9d69</id>
<content type='text'>
[ Upstream commit 73c7733f122e8d0107f88655a12011f68f69e74b ]

When crng_fast_load() is called by add_hwgenerator_randomness(), we
currently will advance to crng_init==1 once we've acquired 64 bytes, and
then throw away the rest of the buffer. Usually, that is not a problem:
When add_hwgenerator_randomness() gets called via EFI or DT during
setup_arch(), there won't be any IRQ randomness. Therefore, the 64 bytes
passed by EFI exactly matches what is needed to advance to crng_init==1.
Usually, DT seems to pass 64 bytes as well -- with one notable exception
being kexec, which hands over 128 bytes of entropy to the kexec'd kernel.
In that case, we'll advance to crng_init==1 once 64 of those bytes are
consumed by crng_fast_load(), but won't continue onward feeding in bytes
to progress to crng_init==2. This commit fixes the issue by feeding
any leftover bytes into the next phase in add_hwgenerator_randomness().

[linux@dominikbrodowski.net: rewrite commit message]
Signed-off-by: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 73c7733f122e8d0107f88655a12011f68f69e74b ]

When crng_fast_load() is called by add_hwgenerator_randomness(), we
currently will advance to crng_init==1 once we've acquired 64 bytes, and
then throw away the rest of the buffer. Usually, that is not a problem:
When add_hwgenerator_randomness() gets called via EFI or DT during
setup_arch(), there won't be any IRQ randomness. Therefore, the 64 bytes
passed by EFI exactly matches what is needed to advance to crng_init==1.
Usually, DT seems to pass 64 bytes as well -- with one notable exception
being kexec, which hands over 128 bytes of entropy to the kexec'd kernel.
In that case, we'll advance to crng_init==1 once 64 of those bytes are
consumed by crng_fast_load(), but won't continue onward feeding in bytes
to progress to crng_init==2. This commit fixes the issue by feeding
any leftover bytes into the next phase in add_hwgenerator_randomness().

[linux@dominikbrodowski.net: rewrite commit message]
Signed-off-by: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>char/mwave: Adjust io port register size</title>
<updated>2022-01-27T11:02:05+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2021-12-03T08:42:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4fef06f38906a04c3bd71756ff5cf6bf5ba288dc'/>
<id>4fef06f38906a04c3bd71756ff5cf6bf5ba288dc</id>
<content type='text'>
[ Upstream commit f5912cc19acd7c24b2dbf65a6340bf194244f085 ]

Using MKWORD() on a byte-sized variable results in OOB read. Expand the
size of the reserved area so both MKWORD and MKBYTE continue to work
without overflow. Silences this warning on a -Warray-bounds build:

drivers/char/mwave/3780i.h:346:22: error: array subscript 'short unsigned int[0]' is partly outside array bounds of 'DSP_ISA_SLAVE_CONTROL[1]' [-Werror=array-bounds]
  346 | #define MKWORD(var) (*((unsigned short *)(&amp;var)))
      |                     ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/char/mwave/3780i.h:356:40: note: in definition of macro 'OutWordDsp'
  356 | #define OutWordDsp(index,value)   outw(value,usDspBaseIO+index)
      |                                        ^~~~~
drivers/char/mwave/3780i.c:373:41: note: in expansion of macro 'MKWORD'
  373 |         OutWordDsp(DSP_IsaSlaveControl, MKWORD(rSlaveControl));
      |                                         ^~~~~~
drivers/char/mwave/3780i.c:358:31: note: while referencing 'rSlaveControl'
  358 |         DSP_ISA_SLAVE_CONTROL rSlaveControl;
      |                               ^~~~~~~~~~~~~

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20211203084206.3104326-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f5912cc19acd7c24b2dbf65a6340bf194244f085 ]

Using MKWORD() on a byte-sized variable results in OOB read. Expand the
size of the reserved area so both MKWORD and MKBYTE continue to work
without overflow. Silences this warning on a -Warray-bounds build:

drivers/char/mwave/3780i.h:346:22: error: array subscript 'short unsigned int[0]' is partly outside array bounds of 'DSP_ISA_SLAVE_CONTROL[1]' [-Werror=array-bounds]
  346 | #define MKWORD(var) (*((unsigned short *)(&amp;var)))
      |                     ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/char/mwave/3780i.h:356:40: note: in definition of macro 'OutWordDsp'
  356 | #define OutWordDsp(index,value)   outw(value,usDspBaseIO+index)
      |                                        ^~~~~
drivers/char/mwave/3780i.c:373:41: note: in expansion of macro 'MKWORD'
  373 |         OutWordDsp(DSP_IsaSlaveControl, MKWORD(rSlaveControl));
      |                                         ^~~~~~
drivers/char/mwave/3780i.c:358:31: note: while referencing 'rSlaveControl'
  358 |         DSP_ISA_SLAVE_CONTROL rSlaveControl;
      |                               ^~~~~~~~~~~~~

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20211203084206.3104326-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm_tis: Fix an error handling path in 'tpm_tis_core_init()'</title>
<updated>2022-01-27T11:02:01+00:00</updated>
<author>
<name>Christophe Jaillet</name>
<email>christophe.jaillet@wanadoo.fr</email>
</author>
<published>2021-11-06T16:42:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7e58fa6bc6f905f7d4fdf3a479eeff76ebf76ee3'/>
<id>7e58fa6bc6f905f7d4fdf3a479eeff76ebf76ee3</id>
<content type='text'>
[ Upstream commit e96d52822f5ac0a25de78f95cd23421bcbc93584 ]

Commit 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent
queries") has moved some code around without updating the error handling
path.

This is now pointless to 'goto out_err' when neither 'clk_enable()' nor
'ioremap()' have been called yet.

Make a direct return instead to avoid undoing things that have not been
done.

Fixes: 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent queries")
Signed-off-by: Christophe Jaillet &lt;christophe.jaillet@wanadoo.fr&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e96d52822f5ac0a25de78f95cd23421bcbc93584 ]

Commit 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent
queries") has moved some code around without updating the error handling
path.

This is now pointless to 'goto out_err' when neither 'clk_enable()' nor
'ioremap()' have been called yet.

Make a direct return instead to avoid undoing things that have not been
done.

Fixes: 79ca6f74dae0 ("tpm: fix Atmel TPM crash caused by too frequent queries")
Signed-off-by: Christophe Jaillet &lt;christophe.jaillet@wanadoo.fr&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tpm: add request_locality before write TPM_INT_ENABLE</title>
<updated>2022-01-27T11:02:01+00:00</updated>
<author>
<name>Chen Jun</name>
<email>chenjun102@huawei.com</email>
</author>
<published>2021-10-13T06:25:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=159610c96f14129f696256dd5056c76b2f3d1c0f'/>
<id>159610c96f14129f696256dd5056c76b2f3d1c0f</id>
<content type='text'>
[ Upstream commit 0ef333f5ba7f24f5d8478425c163d3097f1c7afd ]

Locality is not appropriately requested before writing the int mask.
Add the missing boilerplate.

Fixes: e6aef069b6e9 ("tpm_tis: convert to using locality callbacks")
Signed-off-by: Chen Jun &lt;chenjun102@huawei.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0ef333f5ba7f24f5d8478425c163d3097f1c7afd ]

Locality is not appropriately requested before writing the int mask.
Add the missing boilerplate.

Fixes: e6aef069b6e9 ("tpm_tis: convert to using locality callbacks")
Signed-off-by: Chen Jun &lt;chenjun102@huawei.com&gt;
Reviewed-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>random: fix crash on multiple early calls to add_bootloader_randomness()</title>
<updated>2022-01-16T08:11:14+00:00</updated>
<author>
<name>Dominik Brodowski</name>
<email>linux@dominikbrodowski.net</email>
</author>
<published>2021-12-29T21:10:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e65c79ffa96196f8df8a88f29970c8e4b458c2f8'/>
<id>e65c79ffa96196f8df8a88f29970c8e4b458c2f8</id>
<content type='text'>
commit f7e67b8e803185d0aabe7f29d25a35c8be724a78 upstream.

Currently, if CONFIG_RANDOM_TRUST_BOOTLOADER is enabled, multiple calls
to add_bootloader_randomness() are broken and can cause a NULL pointer
dereference, as noted by Ivan T. Ivanov. This is not only a hypothetical
problem, as qemu on arm64 may provide bootloader entropy via EFI and via
devicetree.

On the first call to add_hwgenerator_randomness(), crng_fast_load() is
executed, and if the seed is long enough, crng_init will be set to 1.
On subsequent calls to add_bootloader_randomness() and then to
add_hwgenerator_randomness(), crng_fast_load() will be skipped. Instead,
wait_event_interruptible() and then credit_entropy_bits() will be called.
If the entropy count for that second seed is large enough, that proceeds
to crng_reseed().

However, both wait_event_interruptible() and crng_reseed() depends
(at least in numa_crng_init()) on workqueues. Therefore, test whether
system_wq is already initialized, which is a sufficient indicator that
workqueue_init_early() has progressed far enough.

If we wind up hitting the !system_wq case, we later want to do what
would have been done there when wqs are up, so set a flag, and do that
work later from the rand_initialize() call.

Reported-by: Ivan T. Ivanov &lt;iivanov@suse.de&gt;
Fixes: 18b915ac6b0a ("efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness")
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
[Jason: added crng_need_done state and related logic.]
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f7e67b8e803185d0aabe7f29d25a35c8be724a78 upstream.

Currently, if CONFIG_RANDOM_TRUST_BOOTLOADER is enabled, multiple calls
to add_bootloader_randomness() are broken and can cause a NULL pointer
dereference, as noted by Ivan T. Ivanov. This is not only a hypothetical
problem, as qemu on arm64 may provide bootloader entropy via EFI and via
devicetree.

On the first call to add_hwgenerator_randomness(), crng_fast_load() is
executed, and if the seed is long enough, crng_init will be set to 1.
On subsequent calls to add_bootloader_randomness() and then to
add_hwgenerator_randomness(), crng_fast_load() will be skipped. Instead,
wait_event_interruptible() and then credit_entropy_bits() will be called.
If the entropy count for that second seed is large enough, that proceeds
to crng_reseed().

However, both wait_event_interruptible() and crng_reseed() depends
(at least in numa_crng_init()) on workqueues. Therefore, test whether
system_wq is already initialized, which is a sufficient indicator that
workqueue_init_early() has progressed far enough.

If we wind up hitting the !system_wq case, we later want to do what
would have been done there when wqs are up, so set a flag, and do that
work later from the rand_initialize() call.

Reported-by: Ivan T. Ivanov &lt;iivanov@suse.de&gt;
Fixes: 18b915ac6b0a ("efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness")
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
[Jason: added crng_need_done state and related logic.]
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>random: fix data race on crng init time</title>
<updated>2022-01-16T08:11:14+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2021-12-20T22:41:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=49005ba11d05506b3841b134daa346fee367825b'/>
<id>49005ba11d05506b3841b134daa346fee367825b</id>
<content type='text'>
commit 009ba8568be497c640cab7571f7bfd18345d7b24 upstream.

_extract_crng() does plain loads of crng-&gt;init_time and
crng_global_init_time, which causes undefined behavior if
crng_reseed() and RNDRESEEDCRNG modify these corrently.

Use READ_ONCE() and WRITE_ONCE() to make the behavior defined.

Don't fix the race on crng-&gt;init_time by protecting it with crng-&gt;lock,
since it's not a problem for duplicate reseedings to occur.  I.e., the
lockless access with READ_ONCE() is fine.

Fixes: d848e5f8e1eb ("random: add new ioctl RNDRESEEDCRNG")
Fixes: e192be9d9a30 ("random: replace non-blocking pool with a Chacha20-based CRNG")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 009ba8568be497c640cab7571f7bfd18345d7b24 upstream.

_extract_crng() does plain loads of crng-&gt;init_time and
crng_global_init_time, which causes undefined behavior if
crng_reseed() and RNDRESEEDCRNG modify these corrently.

Use READ_ONCE() and WRITE_ONCE() to make the behavior defined.

Don't fix the race on crng-&gt;init_time by protecting it with crng-&gt;lock,
since it's not a problem for duplicate reseedings to occur.  I.e., the
lockless access with READ_ONCE() is fine.

Fixes: d848e5f8e1eb ("random: add new ioctl RNDRESEEDCRNG")
Fixes: e192be9d9a30 ("random: replace non-blocking pool with a Chacha20-based CRNG")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>random: fix data race on crng_node_pool</title>
<updated>2022-01-16T08:11:14+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2021-12-20T22:41:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c1bdbdc7f5e2c73f2ca3d5063aa5980f8d9302dd'/>
<id>c1bdbdc7f5e2c73f2ca3d5063aa5980f8d9302dd</id>
<content type='text'>
commit 5d73d1e320c3fd94ea15ba5f79301da9a8bcc7de upstream.

extract_crng() and crng_backtrack_protect() load crng_node_pool with a
plain load, which causes undefined behavior if do_numa_crng_init()
modifies it concurrently.

Fix this by using READ_ONCE().  Note: as per the previous discussion
https://lore.kernel.org/lkml/20211219025139.31085-1-ebiggers@kernel.org/T/#u,
READ_ONCE() is believed to be sufficient here, and it was requested that
it be used here instead of smp_load_acquire().

Also change do_numa_crng_init() to set crng_node_pool using
cmpxchg_release() instead of mb() + cmpxchg(), as the former is
sufficient here but is more lightweight.

Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly userspace programs")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5d73d1e320c3fd94ea15ba5f79301da9a8bcc7de upstream.

extract_crng() and crng_backtrack_protect() load crng_node_pool with a
plain load, which causes undefined behavior if do_numa_crng_init()
modifies it concurrently.

Fix this by using READ_ONCE().  Note: as per the previous discussion
https://lore.kernel.org/lkml/20211219025139.31085-1-ebiggers@kernel.org/T/#u,
READ_ONCE() is believed to be sufficient here, and it was requested that
it be used here instead of smp_load_acquire().

Also change do_numa_crng_init() to set crng_node_pool using
cmpxchg_release() instead of mb() + cmpxchg(), as the former is
sufficient here but is more lightweight.

Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly userspace programs")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus-5.16-3' of git://github.com/cminyard/linux-ipmi</title>
<updated>2021-12-22T18:11:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-12-22T18:11:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=074004058094a07f784c8162153fa44c1e05596b'/>
<id>074004058094a07f784c8162153fa44c1e05596b</id>
<content type='text'>
Pull IPMI fixes from Corey Minyard:
 "Fix some IPMI crashes

  Some crash fixes have come in dealing with various error handling
  issues. They have sat in next for 5 days or more without issue, and
  they are fairly critical"

* tag 'for-linus-5.16-3' of git://github.com/cminyard/linux-ipmi:
  ipmi: Fix UAF when uninstall ipmi_si and ipmi_msghandler module
  ipmi: fix initialization when workqueue allocation fails
  ipmi: bail out if init_srcu_struct fails
  ipmi: ssif: initialize ssif_info-&gt;client early
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull IPMI fixes from Corey Minyard:
 "Fix some IPMI crashes

  Some crash fixes have come in dealing with various error handling
  issues. They have sat in next for 5 days or more without issue, and
  they are fairly critical"

* tag 'for-linus-5.16-3' of git://github.com/cminyard/linux-ipmi:
  ipmi: Fix UAF when uninstall ipmi_si and ipmi_msghandler module
  ipmi: fix initialization when workqueue allocation fails
  ipmi: bail out if init_srcu_struct fails
  ipmi: ssif: initialize ssif_info-&gt;client early
</pre>
</div>
</content>
</entry>
</feed>
