As reported by nixiaoming, with some minor clarifications:

1) memory leak in ramoops_register_dummy():
   dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
   but no kfree() if platform_device_register_data() fails.

2) memory leak in ramoops_init():
   Missing platform_device_unregister(dummy) and kfree(dummy_data)
   if platform_driver_register(&ramoops_driver) fails.

I've clarified the purpose of ramoops_register_dummy(), and added a
common cleanup routine for all three failure paths to call.

Reported-by: nixiaoming <nixiaoming@huawei.com>
Cc: stable@vger.kernel.org
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

persistent_ram_vmap() returns the page start vaddr.
persistent_ram_iomap() supports non-page-aligned mapping.

persistent_ram_buffer_map() always adds offset-in-page to the vaddr
returned from these two functions, which causes incorrect mapping of
non-page-aligned persistent ram buffer.

By default ftrace_size is 4096 and max_ftrace_cnt is nr_cpu_ids. Without
this patch, the zone_sz in ramoops_init_przs() is 4096/nr_cpu_ids which
might not be page aligned. If the offset-in-page > 2048, the vaddr will be
in next page. If the next page is not mapped, it will cause kernel panic:

[    0.074231] BUG: unable to handle kernel paging request at ffffa19e0081b000
...
[    0.075000] RIP: 0010:persistent_ram_new+0x1f8/0x39f
...
[    0.075000] Call Trace:
[    0.075000]  ramoops_init_przs.part.10.constprop.15+0x105/0x260
[    0.075000]  ramoops_probe+0x232/0x3a0
[    0.075000]  platform_drv_probe+0x3e/0xa0
[    0.075000]  driver_probe_device+0x2cd/0x400
[    0.075000]  __driver_attach+0xe4/0x110
[    0.075000]  ? driver_probe_device+0x400/0x400
[    0.075000]  bus_for_each_dev+0x70/0xa0
[    0.075000]  driver_attach+0x1e/0x20
[    0.075000]  bus_add_driver+0x159/0x230
[    0.075000]  ? do_early_param+0x95/0x95
[    0.075000]  driver_register+0x70/0xc0
[    0.075000]  ? init_pstore_fs+0x4d/0x4d
[    0.075000]  __platform_driver_register+0x36/0x40
[    0.075000]  ramoops_init+0x12f/0x131
[    0.075000]  do_one_initcall+0x4d/0x12c
[    0.075000]  ? do_early_param+0x95/0x95
[    0.075000]  kernel_init_freeable+0x19b/0x222
[    0.075000]  ? rest_init+0xbb/0xbb
[    0.075000]  kernel_init+0xe/0xfc
[    0.075000]  ret_from_fork+0x3a/0x50

Signed-off-by: Bin Yang <bin.yang@intel.com>
[kees: add comments describing the mapping differences, updated commit log]
Fixes: 24c3d2f342ed ("staging: android: persistent_ram: Make it possible to use memory outside of bootmem")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>

This patch added the 6th compression algorithm support for pstore: zstd.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

The pstore conversion to timespec64 introduces its own method of passing
seconds into sscanf() and sprintf() type functions to work around the
timespec64 definition on 64-bit systems that redefine it to 'timespec'.

That hack is now finally getting removed, but that means we get a (harmless)
warning once both patches are merged:

fs/pstore/ram.c: In function 'ramoops_read_kmsg_hdr':
fs/pstore/ram.c:39:29: error: format '%ld' expects argument of type 'long int *', but argument 3 has type 'time64_t *' {aka 'long long int *'} [-Werror=format=]
 #define RAMOOPS_KERNMSG_HDR "===="
                             ^~~~~~
fs/pstore/ram.c:167:21: note: in expansion of macro 'RAMOOPS_KERNMSG_HDR'

This removes the pstore specific workaround and uses the same method that
we have in place for all other functions that print a timespec64.

Related to this, I found that the kasprintf() output contains an incorrect
nanosecond values for any number starting with zeroes, and I adapt the
format string accordingly.

Link: https://lkml.org/lkml/2018/5/19/115
Link: https://lkml.org/lkml/2018/5/16/1080
Fixes: 0f0d83b99ef7 ("pstore: Convert internal records to timespec64")
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

struct timespec is not y2038 safe. Transition vfs to use
y2038 safe struct timespec64 instead.

The change was made with the help of the following cocinelle
script. This catches about 80% of the changes.
All the header file and logic changes are included in the
first 5 rules. The rest are trivial substitutions.
I avoid changing any of the function signatures or any other
filesystem specific data structures to keep the patch simple
for review.

The script can be a little shorter by combining different cases.
But, this version was sufficient for my usecase.

virtual patch

@ depends on patch @
identifier now;
@@
- struct timespec
+ struct timespec64
  current_time ( ... )
  {
- struct timespec now = current_kernel_time();
+ struct timespec64 now = current_kernel_time64();
  ...
- return timespec_trunc(
+ return timespec64_trunc(
  ... );
  }

@ depends on patch @
identifier xtime;
@@
 struct \( iattr \| inode \| kstat \) {
 ...
-       struct timespec xtime;
+       struct timespec64 xtime;
 ...
 }

@ depends on patch @
identifier t;
@@
 struct inode_operations {
 ...
int (*update_time) (...,
-       struct timespec t,
+       struct timespec64 t,
...);
 ...
 }

@ depends on patch @
identifier t;
identifier fn_update_time =~ "update_time$";
@@
 fn_update_time (...,
- struct timespec *t,
+ struct timespec64 *t,
 ...) { ... }

@ depends on patch @
identifier t;
@@
lease_get_mtime( ... ,
- struct timespec *t
+ struct timespec64 *t
  ) { ... }

@te depends on patch forall@
identifier ts;
local idexpression struct inode *inode_node;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
identifier fn_update_time =~ "update_time$";
identifier fn;
expression e, E3;
local idexpression struct inode *node1;
local idexpression struct inode *node2;
local idexpression struct iattr *attr1;
local idexpression struct iattr *attr2;
local idexpression struct iattr attr;
identifier i_xtime1 =~ "^i_[acm]time$";
identifier i_xtime2 =~ "^i_[acm]time$";
identifier ia_xtime1 =~ "^ia_[acm]time$";
identifier ia_xtime2 =~ "^ia_[acm]time$";
@@
(
(
- struct timespec ts;
+ struct timespec64 ts;
|
- struct timespec ts = current_time(inode_node);
+ struct timespec64 ts = current_time(inode_node);
)

<+... when != ts
(
- timespec_equal(&inode_node->i_xtime, &ts)
+ timespec64_equal(&inode_node->i_xtime, &ts)
|
- timespec_equal(&ts, &inode_node->i_xtime)
+ timespec64_equal(&ts, &inode_node->i_xtime)
|
- timespec_compare(&inode_node->i_xtime, &ts)
+ timespec64_compare(&inode_node->i_xtime, &ts)
|
- timespec_compare(&ts, &inode_node->i_xtime)
+ timespec64_compare(&ts, &inode_node->i_xtime)
|
ts = current_time(e)
|
fn_update_time(..., &ts,...)
|
inode_node->i_xtime = ts
|
node1->i_xtime = ts
|
ts = inode_node->i_xtime
|
<+... attr1->ia_xtime ...+> = ts
|
ts = attr1->ia_xtime
|
ts.tv_sec
|
ts.tv_nsec
|
btrfs_set_stack_timespec_sec(..., ts.tv_sec)
|
btrfs_set_stack_timespec_nsec(..., ts.tv_nsec)
|
- ts = timespec64_to_timespec(
+ ts =
...
-)
|
- ts = ktime_to_timespec(
+ ts = ktime_to_timespec64(
...)
|
- ts = E3
+ ts = timespec_to_timespec64(E3)
|
- ktime_get_real_ts(&ts)
+ ktime_get_real_ts64(&ts)
|
fn(...,
- ts
+ timespec64_to_timespec(ts)
,...)
)
...+>
(
<... when != ts
- return ts;
+ return timespec64_to_timespec(ts);
...>
)
|
- timespec_equal(&node1->i_xtime1, &node2->i_xtime2)
+ timespec64_equal(&node1->i_xtime2, &node2->i_xtime2)
|
- timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2)
+ timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2)
|
- timespec_compare(&node1->i_xtime1, &node2->i_xtime2)
+ timespec64_compare(&node1->i_xtime1, &node2->i_xtime2)
|
node1->i_xtime1 =
- timespec_trunc(attr1->ia_xtime1,
+ timespec64_trunc(attr1->ia_xtime1,
...)
|
- attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2,
+ attr1->ia_xtime1 =  timespec64_trunc(attr2->ia_xtime2,
...)
|
- ktime_get_real_ts(&attr1->ia_xtime1)
+ ktime_get_real_ts64(&attr1->ia_xtime1)
|
- ktime_get_real_ts(&attr.ia_xtime1)
+ ktime_get_real_ts64(&attr.ia_xtime1)
)

@ depends on patch @
struct inode *node;
struct iattr *attr;
identifier fn;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
expression e;
@@
(
- fn(node->i_xtime);
+ fn(timespec64_to_timespec(node->i_xtime));
|
 fn(...,
- node->i_xtime);
+ timespec64_to_timespec(node->i_xtime));
|
- e = fn(attr->ia_xtime);
+ e = fn(timespec64_to_timespec(attr->ia_xtime));
)

@ depends on patch forall @
struct inode *node;
struct iattr *attr;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
identifier fn;
@@
{
+ struct timespec ts;
<+...
(
+ ts = timespec64_to_timespec(node->i_xtime);
fn (...,
- &node->i_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
fn (...,
- &attr->ia_xtime,
+ &ts,
...);
)
...+>
}

@ depends on patch forall @
struct inode *node;
struct iattr *attr;
struct kstat *stat;
identifier ia_xtime =~ "^ia_[acm]time$";
identifier i_xtime =~ "^i_[acm]time$";
identifier xtime =~ "^[acm]time$";
identifier fn, ret;
@@
{
+ struct timespec ts;
<+...
(
+ ts = timespec64_to_timespec(node->i_xtime);
ret = fn (...,
- &node->i_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(node->i_xtime);
ret = fn (...,
- &node->i_xtime);
+ &ts);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
ret = fn (...,
- &attr->ia_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
ret = fn (...,
- &attr->ia_xtime);
+ &ts);
|
+ ts = timespec64_to_timespec(stat->xtime);
ret = fn (...,
- &stat->xtime);
+ &ts);
)
...+>
}

@ depends on patch @
struct inode *node;
struct inode *node2;
identifier i_xtime1 =~ "^i_[acm]time$";
identifier i_xtime2 =~ "^i_[acm]time$";
identifier i_xtime3 =~ "^i_[acm]time$";
struct iattr *attrp;
struct iattr *attrp2;
struct iattr attr ;
identifier ia_xtime1 =~ "^ia_[acm]time$";
identifier ia_xtime2 =~ "^ia_[acm]time$";
struct kstat *stat;
struct kstat stat1;
struct timespec64 ts;
identifier xtime =~ "^[acmb]time$";
expression e;
@@
(
( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1  ;
|
 node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \);
|
 node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \);
|
 node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \);
|
 stat->xtime = node2->i_xtime1;
|
 stat1.xtime = node2->i_xtime1;
|
( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1  ;
|
( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2;
|
- e = node->i_xtime1;
+ e = timespec64_to_timespec( node->i_xtime1 );
|
- e = attrp->ia_xtime1;
+ e = timespec64_to_timespec( attrp->ia_xtime1 );
|
node->i_xtime1 = current_time(...);
|
 node->i_xtime2 = node->i_xtime1 = node->i_xtime3 =
- e;
+ timespec_to_timespec64(e);
|
 node->i_xtime1 = node->i_xtime3 =
- e;
+ timespec_to_timespec64(e);
|
- node->i_xtime1 = e;
+ node->i_xtime1 = timespec_to_timespec64(e);
)

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: <anton@tuxera.com>
Cc: <balbi@kernel.org>
Cc: <bfields@fieldses.org>
Cc: <darrick.wong@oracle.com>
Cc: <dhowells@redhat.com>
Cc: <dsterba@suse.com>
Cc: <dwmw2@infradead.org>
Cc: <hch@lst.de>
Cc: <hirofumi@mail.parknet.co.jp>
Cc: <hubcap@omnibond.com>
Cc: <jack@suse.com>
Cc: <jaegeuk@kernel.org>
Cc: <jaharkes@cs.cmu.edu>
Cc: <jslaby@suse.com>
Cc: <keescook@chromium.org>
Cc: <mark@fasheh.com>
Cc: <miklos@szeredi.hu>
Cc: <nico@linaro.org>
Cc: <reiserfs-devel@vger.kernel.org>
Cc: <richard@nod.at>
Cc: <sage@redhat.com>
Cc: <sfrench@samba.org>
Cc: <swhiteho@redhat.com>
Cc: <tj@kernel.org>
Cc: <trond.myklebust@primarydata.com>
Cc: <tytso@mit.edu>
Cc: <viro@zeniv.linux.org.uk>

This prepares pstore for converting the VFS layer to timespec64.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>

Commit 58eb5b670747 ("pstore: fix crypto dependencies") fixed up the crypto
dependencies but missed the case when no compression is selected.

With CONFIG_PSTORE=y, CONFIG_PSTORE_COMPRESS=n  and CONFIG_CRYPTO=m we see
the following link error:

fs/pstore/platform.o: In function `pstore_register':
(.text+0x1b1): undefined reference to `crypto_has_alg'
(.text+0x205): undefined reference to `crypto_alloc_base'
fs/pstore/platform.o: In function `pstore_unregister':
(.text+0x3b0): undefined reference to `crypto_destroy_tfm'

Fix this by checking at compile-time if CONFIG_PSTORE_COMPRESS is enabled.

Fixes: 58eb5b670747 ("pstore: fix crypto dependencies")
Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kees Cook <keescook@chromium.org>

The new crypto API use causes some problems with Kconfig dependencies,
including this link error:

fs/pstore/platform.o: In function `pstore_register':
platform.c:(.text+0x248): undefined reference to `crypto_has_alg'
platform.c:(.text+0x2a0): undefined reference to `crypto_alloc_base'
fs/pstore/platform.o: In function `pstore_unregister':
platform.c:(.text+0x498): undefined reference to `crypto_destroy_tfm'
crypto/lz4hc.o: In function `lz4hc_sdecompress':
lz4hc.c:(.text+0x1a): undefined reference to `LZ4_decompress_safe'
crypto/lz4hc.o: In function `lz4hc_decompress_crypto':
lz4hc.c:(.text+0x5a): undefined reference to `LZ4_decompress_safe'
crypto/lz4hc.o: In function `lz4hc_scompress':
lz4hc.c:(.text+0xaa): undefined reference to `LZ4_compress_HC'
crypto/lz4hc.o: In function `lz4hc_mod_init':
lz4hc.c:(.init.text+0xf): undefined reference to `crypto_register_alg'
lz4hc.c:(.init.text+0x1f): undefined reference to `crypto_register_scomp'
lz4hc.c:(.init.text+0x2f): undefined reference to `crypto_unregister_alg'

The problem is that with CONFIG_CRYPTO=m, we must not 'select CRYPTO_LZ4'
from a bool symbol, or call crypto API functions from a built-in
module.

This turns the sub-options into 'tristate' ones so the dependencies
are honored, and makes the pstore itself select the crypto core
if necessary.

Fixes: cb3bee0369bc ("pstore: Use crypto compress API")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kees Cook <keescook@chromium.org>

In the pstore compression part, we use zlib/lzo/lz4/lz4hc/842
compression algorithm API to implement pstore compression backends. But
there are many repeat codes in these implementations. This patch uses
crypto compress API to simplify these codes.

1) rewrite allocate_buf_for_compression, free_buf_for_compression,
pstore_compress, pstore_decompress functions using crypto compress API.
2) drop compress, decompress, allocate, free functions in pstore_zbackend,
and add zbufsize function to get each different compress buffer size.
3) use late_initcall to call ramoops_init later, to make sure the crypto
subsystem has already initialized.
4) use 'unsigned int' type instead of 'size_t' in pstore_compress,
pstore_decompress functions' length arguments.
5) rename 'zlib' to 'deflate' to follow the crypto API's name convention.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
[kees: tweaked error messages on allocation failures and Kconfig help]
Signed-off-by: Kees Cook <keescook@chromium.org>

Instead of using a stack VLA for the parity workspace, preallocate a
memory region. The preallocation is done to keep from needing to perform
allocations during crash dump writing, etc. This also fixes a missed
release of librs on free.

Signed-off-by: Kees Cook <keescook@chromium.org>