DPDK patches and discussions
 help / color / Atom feed
From: Aaron Conole <aconole@redhat.com>
To: David Marchand <david.marchand@redhat.com>
Cc: dev <dev@dpdk.org>, Harry van Haaren <harry.van.haaren@intel.com>,
	Bruce Richardson <bruce.richardson@intel.com>,
	Pavan Nikhilesh <pbhagavatula@marvell.com>,
	Gage Eads <gage.eads@intel.com>,
	Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [dpdk-dev] [PATCH] service: don't walk out of bounds when checking services
Date: Tue, 03 Dec 2019 10:10:05 -0500
Message-ID: <f7tblsp1m42.fsf@dhcp-25.97.bos.redhat.com> (raw)
In-Reply-To: <CAJFAV8wcZxCRo2HLvTpU8=ieLjGdcr+0BiEBFbCXiqV+DNK+VQ@mail.gmail.com>

David Marchand <david.marchand@redhat.com> writes:

> On Tue, Nov 26, 2019 at 3:56 PM Aaron Conole <aconole@redhat.com> wrote:
>>
>> The service_valid call is used without properly bounds checking the
>> input parameter.  Almost all instances of the service_valid call are
>> inside a for() loop that prevents excessive walks, but some of the
>> public APIs don't bounds check and will pass invalid arguments.
>>
>> Prevent this by using SERVICE_GET_OR_ERR_RET where it makes sense,
>> and adding a bounds check to one service_valid() use.
>>
>> Fixes: 8d39d3e237c2 ("service: fix race in service on app lcore function")
>> Fixes: e9139a32f6e8 ("service: add function to run on app lcore")
>> Fixes: e30dd31847d2 ("service: add mechanism for quiescing")
>> Signed-off-by: Aaron Conole <aconole@redhat.com>
>> ---
>>  lib/librte_eal/common/rte_service.c | 23 +++++++++++------------
>>  1 file changed, 11 insertions(+), 12 deletions(-)
>>
>> diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
>> index 79235c03f8..73de7bbade 100644
>> --- a/lib/librte_eal/common/rte_service.c
>> +++ b/lib/librte_eal/common/rte_service.c
>> @@ -345,11 +345,12 @@ rte_service_runner_do_callback(struct rte_service_spec_impl *s,
>>
>>
>>  static inline int32_t
>> -service_run(uint32_t i, struct core_state *cs, uint64_t service_mask)
>> +service_run(uint32_t i, struct core_state *cs, uint64_t service_mask,
>> +           struct rte_service_spec_impl *s)
>>  {
>> -       if (!service_valid(i))
>> -               return -EINVAL;
>> -       struct rte_service_spec_impl *s = &rte_services[i];
>> +       if (!s)
>> +               SERVICE_VALID_GET_OR_ERR_RET(i, s, -EINVAL);
>> +
>
> No need to check the service if we ensure that the passed index is valid.
> See below.

Okay.  I will document that then ;)

>
>>         if (s->comp_runstate != RUNSTATE_RUNNING ||
>>                         s->app_runstate != RUNSTATE_RUNNING ||
>>                         !(service_mask & (UINT64_C(1) << i))) {
>> @@ -383,7 +384,7 @@ rte_service_may_be_active(uint32_t id)
>>         int32_t lcore_count = rte_service_lcore_list(ids, RTE_MAX_LCORE);
>>         int i;
>>
>> -       if (!service_valid(id))
>> +       if (id >= RTE_SERVICE_NUM_MAX || !service_valid(id))
>>                 return -EINVAL;
>>
>>         for (i = 0; i < lcore_count; i++) {
>> @@ -397,12 +398,10 @@ rte_service_may_be_active(uint32_t id)
>>  int32_t
>>  rte_service_run_iter_on_app_lcore(uint32_t id, uint32_t serialize_mt_unsafe)
>>  {
>> -       /* run service on calling core, using all-ones as the service mask */
>> -       if (!service_valid(id))
>> -               return -EINVAL;
>> -
>>         struct core_state *cs = &lcore_states[rte_lcore_id()];
>> -       struct rte_service_spec_impl *s = &rte_services[id];
>> +       struct rte_service_spec_impl *s;
>> +
>> +       SERVICE_VALID_GET_OR_ERR_RET(id, s, -EINVAL);
>>
>>         /* Atomically add this core to the mapped cores first, then examine if
>>          * we can run the service. This avoids a race condition between
>> @@ -418,7 +417,7 @@ rte_service_run_iter_on_app_lcore(uint32_t id, uint32_t serialize_mt_unsafe)
>>                 return -EBUSY;
>>         }
>>
>> -       int ret = service_run(id, cs, UINT64_MAX);
>> +       int ret = service_run(id, cs, UINT64_MAX, s);
>>
>>         if (serialize_mt_unsafe)
>>                 rte_atomic32_dec(&s->num_mapped_cores);
>> @@ -439,7 +438,7 @@ rte_service_runner_func(void *arg)
>>
>>                 for (i = 0; i < RTE_SERVICE_NUM_MAX; i++) {
>>                         /* return value ignored as no change to code flow */
>
> if (!service_valid(idx))
>     continue;
>
> Plus, if we add this check here, thenall loops in this file are consistent.
> WDYT?

Agreed - it's better.  Okay.


  reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-26 14:56 Aaron Conole
2019-12-02 16:16 ` Eads, Gage
2019-12-02 16:19 ` David Marchand
2019-12-03 15:10   ` Aaron Conole [this message]
2019-12-03 21:15 ` [dpdk-dev] [PATCH v2] " Aaron Conole
2019-12-04  8:33   ` David Marchand
2019-12-04  8:34     ` David Marchand
2019-12-20 14:43       ` David Marchand
2020-02-07 12:04         ` Kevin Traynor
2020-02-07 14:27           ` Aaron Conole
2020-02-14 16:38             ` Kevin Traynor

Reply instructions:

You may reply publically 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=f7tblsp1m42.fsf@dhcp-25.97.bos.redhat.com \
    --to=aconole@redhat.com \
    --cc=bruce.richardson@intel.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=gage.eads@intel.com \
    --cc=harry.van.haaren@intel.com \
    --cc=pbhagavatula@marvell.com \
    --cc=thomas@monjalon.net \
    /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

DPDK patches and discussions

Archives are clonable:
	git clone --mirror http://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ http://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev


Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/ public-inbox