linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vlastimil Babka <vbabka@suse.cz>
To: Imran Khan <imran.f.khan@oracle.com>,
	geert@linux-m68k.org, akpm@linux-foundation.org,
	ryabinin.a.a@gmail.com, glider@google.com, andreyknvl@gmail.com,
	dvyukov@google.com
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v2 1/2] lib, stackdepot: check stackdepot handle before accessing slabs.
Date: Thu, 2 Sep 2021 09:53:48 +0200	[thread overview]
Message-ID: <fe94ffd8-d235-87d8-9c3d-80f7f73e0c4e@suse.cz> (raw)
In-Reply-To: <20210902000154.1096484-2-imran.f.khan@oracle.com>

On 9/2/21 02:01, Imran Khan wrote:
> stack_depot_save allocates slabs that will be used for storing
> objects in future.If this slab allocation fails we may get to
> a situation where space allocation for a new stack_record fails,
> causing stack_depot_save to return 0 as handle.
> If user of this handle ends up invoking stack_depot_fetch with
> this handle value, current implementation of stack_depot_fetch
> will end up using slab from wrong index.
> To avoid this check handle value at the beginning.
> 
> Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
> Suggested-by: Vlastimil Babka <vbabka@suse.cz>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
>  lib/stackdepot.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/lib/stackdepot.c b/lib/stackdepot.c
> index 0a2e417f83cb..67439c082490 100644
> --- a/lib/stackdepot.c
> +++ b/lib/stackdepot.c
> @@ -232,6 +232,9 @@ unsigned int stack_depot_fetch(depot_stack_handle_t handle,
>  	struct stack_record *stack;
>  
>  	*entries = NULL;
> +	if (!handle)
> +		return 0;
> +
>  	if (parts.slabindex > depot_index) {
>  		WARN(1, "slab index %d out of bounds (%d) for stack id %08x\n",
>  			parts.slabindex, depot_index, handle);
> 


  reply	other threads:[~2021-09-02  7:53 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-02  0:01 [RFC PATCH v2 0/2] lib, stackdepot: check stackdepot handle before accessing slabs Imran Khan
2021-09-02  0:01 ` [RFC PATCH v2 1/2] " Imran Khan
2021-09-02  7:53   ` Vlastimil Babka [this message]
2021-09-02  0:01 ` [RFC PATCH v2 2/2] lib, stackdepot: Add helper to print stack entries Imran Khan
2021-09-02  7:55   ` Vlastimil Babka
2021-09-03 16:03     ` Alexander Potapenko
2021-09-14  9:01   ` Vlastimil Babka
2021-09-15  3:29     ` imran.f.khan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=fe94ffd8-d235-87d8-9c3d-80f7f73e0c4e@suse.cz \
    --to=vbabka@suse.cz \
    --cc=akpm@linux-foundation.org \
    --cc=andreyknvl@gmail.com \
    --cc=dvyukov@google.com \
    --cc=geert@linux-m68k.org \
    --cc=glider@google.com \
    --cc=imran.f.khan@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=ryabinin.a.a@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).