linux-toradex.git/lib/stackdepot.c, branch v5.12-rc6

lib: stackdepot: fix ignoring return value warning

2021-02-26T17:41:04+00:00

Fix the below ignoring return value warning for kstrtobool in
is_stack_depot_disabled function.

lib/stackdepot.c: In function 'is_stack_depot_disabled':
lib/stackdepot.c:154:2: warning: ignoring return value of 'kstrtobool'
declared with attribute 'warn_unused_result' [-Wunused-result]

Link: https://lkml.kernel.org/r/1612163048-28026-1-git-send-email-vjitta@codeaurora.org
Fixes: b9779abb09a8 ("lib: stackdepot: add support to disable stack depot")
Signed-off-by: Vijayanand Jitta 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: stackdepot: add support to disable stack depot

2021-02-26T17:41:04+00:00

Add a kernel parameter stack_depot_disable to disable stack depot.  So
that stack hash table doesn't consume any memory when stack depot is
disabled.

The use case is CONFIG_PAGE_OWNER without page_owner=on.  Without this
patch, stackdepot will consume the memory for the hashtable.  By default,
it's 8M which is never trivial.

With this option, in CONFIG_PAGE_OWNER configured system, page_owner=off,
stack_depot_disable in kernel command line, we could save the wasted
memory for the hashtable.

[akpm@linux-foundation.org: fix CONFIG_STACKDEPOT=n build]

Link: https://lkml.kernel.org/r/1611749198-24316-2-git-send-email-vjitta@codeaurora.org
Signed-off-by: Vinayak Menon 
Signed-off-by: Vijayanand Jitta 
Cc: Alexander Potapenko 
Cc: Minchan Kim 
Cc: Yogesh Lal 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: stackdepot: add support to configure STACK_HASH_SIZE

2021-02-26T17:41:04+00:00

Use CONFIG_STACK_HASH_ORDER to configure STACK_HASH_SIZE.

Aim is to have configurable value for  STACK_HASH_SIZE,
so depend on use case one can configure it.

One example is of Page Owner, CONFIG_PAGE_OWNER works only if
page_owner=on via kernel parameter on CONFIG_PAGE_OWNER configured system.
Thus, unless admin enable it via command line option, the stackdepot will
just waste 8M memory without any customer.

Making it configurable and use lower value helps to enable features like
CONFIG_PAGE_OWNER without any significant overhead.

Link: https://lkml.kernel.org/r/1611749198-24316-1-git-send-email-vjitta@codeaurora.org
Signed-off-by: Yogesh Lal 
Signed-off-by: Vinayak Menon 
Signed-off-by: Vijayanand Jitta 
Reviewed-by: Minchan Kim 
Reviewed-by: Alexander Potapenko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/stackdepot.c: use array_size() helper in jhash2()

2020-12-16T06:46:16+00:00

Use array_size() helper instead of the open-coded version in jhash2().
These sorts of multiplication factors need to be wrapped in array_size().

Also, use the preferred form for passing the size of an object type.

Link: https://lkml.kernel.org/r/cb8a682e4bba4dbddd2bd8aca7f8c02fea89639b.1601565471.git.gustavoars@kernel.org
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/stackdepot.c: use flex_array_size() helper in memcpy()

2020-12-16T06:46:16+00:00

Make use of the flex_array_size() helper to calculate the size of a
flexible array member within an enclosing structure.

This helper offers defense-in-depth against potential integer overflows,
while at the same time makes it explicitly clear that we are dealing with
a flexible array member.

Link: https://lkml.kernel.org/r/186e37fe07196ee41a0e562fa8a8cb7a01112ec5.1601565471.git.gustavoars@kernel.org
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/stackdepot.c: replace one-element array with flexible-array member

2020-12-16T06:46:16+00:00

Patch series "lib/stackdepot.c: Replace one-element array with flexible-array member".

This series aims to replace a one-element array with a flexible-array
member.  Also, make use of the struct_size(), flexible_array_size() and
array_size() helpers.

This patch (of 3):

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure.  Kernel code
should always use “flexible array members”[1] for these cases.  The
older style of one-element or zero-length arrays should no longer be
used[2].

Refactor the code according to the use of a flexible-array member in
struct stack_record, instead of a one-element array, and use the
struct_size() helper to calculate the size for the allocation.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://lkml.kernel.org/r/cover.1601565471.git.gustavoars@kernel.org
Link: https://lore.kernel.org/lkml/5f75876b.x9zdN10esiC0qLHV%25lkp@intel.com/
Link: https://lkml.kernel.org/r/2f1e6a17aaa891ad9c58817cf0a10b8ab8894f59.1601565471.git.gustavoars@kernel.org
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kasan: stackdepot: move filter_irq_stacks() to stackdepot.c

2020-04-07T17:43:43+00:00

filter_irq_stacks() can be used by other tools (e.g.  KMSAN), so it needs
to be moved to a common location.  lib/stackdepot.c seems a good place, as
filter_irq_stacks() is usually applied to the output of
stack_trace_save().

This patch has been previously mailed as part of KMSAN RFC patch series.

[glider@google.co: nds32: linker script: add SOFTIRQENTRY_TEXT\
  Link: http://lkml.kernel.org/r/20200311121002.241430-1-glider@google.com
[glider@google.com: add IRQENTRY_TEXT and SOFTIRQENTRY_TEXT to linker script]
  Link: http://lkml.kernel.org/r/20200311121124.243352-1-glider@google.com
Signed-off-by: Alexander Potapenko 
Signed-off-by: Andrew Morton 
Cc: Vegard Nossum 
Cc: Dmitry Vyukov 
Cc: Marco Elver 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Arnd Bergmann 
Cc: Sergey Senozhatsky 
Link: http://lkml.kernel.org/r/20200220141916.55455-3-glider@google.com
Signed-off-by: Linus Torvalds

lib/stackdepot.c: check depot_index before accessing the stack slab

2020-04-07T17:43:43+00:00

Avoid crashes on corrupted stack ids.  Despite stack ID corruption may
indicate other bugs in the program, we'd better fail gracefully on such
IDs instead of crashing the kernel.

This patch has been previously mailed as part of KMSAN RFC patch series.

Link: http://lkml.kernel.org/r/20200220141916.55455-1-glider@google.com
Signed-off-by: Alexander Potapenko 
Cc: Vegard Nossum 
Cc: Dmitry Vyukov 
Cc: Marco Elver 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Arnd Bergmann 
Cc: Sergey Senozhatsky 
From: Dan Carpenter 
Subject: lib/stackdepot.c: fix a condition in stack_depot_fetch()

We should check for a NULL pointer first before adding the offset.
Otherwise if the pointer is NULL and the offset is non-zero, it will lead
to an Oops.

Fixes: d45048e65a59 ("lib/stackdepot.c: check depot_index before accessing the stack slab")
Signed-off-by: Dan Carpenter 
Signed-off-by: Andrew Morton 
Acked-by: Alexander Potapenko 
Link: http://lkml.kernel.org/r/20200312113006.GA20562@mwanda
Signed-off-by: Linus Torvalds

lib/stackdepot.c: fix global out-of-bounds in stack_slabs

2020-02-21T19:22:15+00:00

Walter Wu has reported a potential case in which init_stack_slab() is
called after stack_slabs[STACK_ALLOC_MAX_SLABS - 1] has already been
initialized.  In that case init_stack_slab() will overwrite
stack_slabs[STACK_ALLOC_MAX_SLABS], which may result in a memory
corruption.

Link: http://lkml.kernel.org/r/20200218102950.260263-1-glider@google.com
Fixes: cd11016e5f521 ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB")
Signed-off-by: Alexander Potapenko 
Reported-by: Walter Wu 
Cc: Dmitry Vyukov 
Cc: Matthias Brugger 
Cc: Thomas Gleixner 
Cc: Josh Poimboeuf 
Cc: Kate Stewart 
Cc: Greg Kroah-Hartman 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/stackdepot: Fix outdated comments

2019-08-19T10:57:28+00:00

Replace "depot_save_stack" with "stack_depot_save" in code comments because
depot_save_stack() was replaced in commit c0cfc337264c ("lib/stackdepot:
Provide functions which operate on plain storage arrays") and removed in
commit 56d8f079c51a ("lib/stackdepot: Remove obsolete functions")

Signed-off-by: Miles Chen 
Signed-off-by: Thomas Gleixner 
Link: https://lkml.kernel.org/r/20190815113246.18478-1-miles.chen@mediatek.com