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10 commits

Author SHA1 Message Date
Ksawlii
88d2580c4c Revert "padata: Honor the caller's alignment in case of chunk_size 0"
This reverts commit d937fc3fb1.
2024-11-24 00:23:30 +01:00
Ksawlii
268d243925 Revert "padata: use integer wrap around to prevent deadlock on seq_nr overflow"
This reverts commit 3b9a874cc0.
2024-11-24 00:23:15 +01:00
VanGiang Nguyen
3b9a874cc0 padata: use integer wrap around to prevent deadlock on seq_nr overflow
commit 9a22b2812393d93d84358a760c347c21939029a6 upstream.

When submitting more than 2^32 padata objects to padata_do_serial, the
current sorting implementation incorrectly sorts padata objects with
overflowed seq_nr, causing them to be placed before existing objects in
the reorder list. This leads to a deadlock in the serialization process
as padata_find_next cannot match padata->seq_nr and pd->processed
because the padata instance with overflowed seq_nr will be selected
next.

To fix this, we use an unsigned integer wrap around to correctly sort
padata objects in scenarios with integer overflow.

Fixes: bfde23ce200e ("padata: unbind parallel jobs from specific CPUs")
Cc: <stable@vger.kernel.org>
Co-developed-by: Christian Gafert <christian.gafert@rohde-schwarz.com>
Signed-off-by: Christian Gafert <christian.gafert@rohde-schwarz.com>
Co-developed-by: Max Ferger <max.ferger@rohde-schwarz.com>
Signed-off-by: Max Ferger <max.ferger@rohde-schwarz.com>
Signed-off-by: Van Giang Nguyen <vangiang.nguyen@rohde-schwarz.com>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:33 +01:00
Kamlesh Gurudasani
d937fc3fb1 padata: Honor the caller's alignment in case of chunk_size 0
[ Upstream commit 24cc57d8faaa4060fd58adf810b858fcfb71a02f ]

In the case where we are forcing the ps.chunk_size to be at least 1,
we are ignoring the caller's alignment.

Move the forcing of ps.chunk_size to be at least 1 before rounding it
up to caller's alignment, so that caller's alignment is honored.

While at it, use max() to force the ps.chunk_size to be at least 1 to
improve readability.

Fixes: 6d45e1c948a8 ("padata: Fix possible divide-by-0 panic in padata_mt_helper()")
Signed-off-by: Kamlesh Gurudasani <kamlesh@ti.com>
Acked-by:  Waiman Long <longman@redhat.com>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:21:17 +01:00
Waiman Long
1c47e0a775 padata: Fix possible divide-by-0 panic in padata_mt_helper()
commit 6d45e1c948a8b7ed6ceddb14319af69424db730c upstream.

We are hit with a not easily reproducible divide-by-0 panic in padata.c at
bootup time.

  [   10.017908] Oops: divide error: 0000 1 PREEMPT SMP NOPTI
  [   10.017908] CPU: 26 PID: 2627 Comm: kworker/u1666:1 Not tainted 6.10.0-15.el10.x86_64 #1
  [   10.017908] Hardware name: Lenovo ThinkSystem SR950 [7X12CTO1WW]/[7X12CTO1WW], BIOS [PSE140J-2.30] 07/20/2021
  [   10.017908] Workqueue: events_unbound padata_mt_helper
  [   10.017908] RIP: 0010:padata_mt_helper+0x39/0xb0
    :
  [   10.017963] Call Trace:
  [   10.017968]  <TASK>
  [   10.018004]  ? padata_mt_helper+0x39/0xb0
  [   10.018084]  process_one_work+0x174/0x330
  [   10.018093]  worker_thread+0x266/0x3a0
  [   10.018111]  kthread+0xcf/0x100
  [   10.018124]  ret_from_fork+0x31/0x50
  [   10.018138]  ret_from_fork_asm+0x1a/0x30
  [   10.018147]  </TASK>

Looking at the padata_mt_helper() function, the only way a divide-by-0
panic can happen is when ps->chunk_size is 0.  The way that chunk_size is
initialized in padata_do_multithreaded(), chunk_size can be 0 when the
min_chunk in the passed-in padata_mt_job structure is 0.

Fix this divide-by-0 panic by making sure that chunk_size will be at least
1 no matter what the input parameters are.

Link: https://lkml.kernel.org/r/20240806174647.1050398-1-longman@redhat.com
Fixes: 004ed42638f4 ("padata: add basic support for multithreaded jobs")
Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Waiman Long <longman@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:20:29 +01:00
Herbert Xu
3588858da3 padata: Disable BH when taking works lock on MT path
[ Upstream commit 58329c4312031603bb1786b44265c26d5065fe72 ]

As the old padata code can execute in softirq context, disable
softirqs for the new padata_do_mutithreaded code too as otherwise
lockdep will get antsy.

Reported-by: syzbot+0cb5bb0f4bf9e79db3b3@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:06 +01:00
Lu Jialin
43e1ef67fc crypto: pcrypt - Fix hungtask for PADATA_RESET
[ Upstream commit 8f4f68e788c3a7a696546291258bfa5fdb215523 ]

We found a hungtask bug in test_aead_vec_cfg as follows:

INFO: task cryptomgr_test:391009 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Call trace:
 __switch_to+0x98/0xe0
 __schedule+0x6c4/0xf40
 schedule+0xd8/0x1b4
 schedule_timeout+0x474/0x560
 wait_for_common+0x368/0x4e0
 wait_for_completion+0x20/0x30
 wait_for_completion+0x20/0x30
 test_aead_vec_cfg+0xab4/0xd50
 test_aead+0x144/0x1f0
 alg_test_aead+0xd8/0x1e0
 alg_test+0x634/0x890
 cryptomgr_test+0x40/0x70
 kthread+0x1e0/0x220
 ret_from_fork+0x10/0x18
 Kernel panic - not syncing: hung_task: blocked tasks

For padata_do_parallel, when the return err is 0 or -EBUSY, it will call
wait_for_completion(&wait->completion) in test_aead_vec_cfg. In normal
case, aead_request_complete() will be called in pcrypt_aead_serial and the
return err is 0 for padata_do_parallel. But, when pinst->flags is
PADATA_RESET, the return err is -EBUSY for padata_do_parallel, and it
won't call aead_request_complete(). Therefore, test_aead_vec_cfg will
hung at wait_for_completion(&wait->completion), which will cause
hungtask.

The problem comes as following:
(padata_do_parallel)                 |
    rcu_read_lock_bh();              |
    err = -EINVAL;                   |   (padata_replace)
                                     |     pinst->flags |= PADATA_RESET;
    err = -EBUSY                     |
    if (pinst->flags & PADATA_RESET) |
        rcu_read_unlock_bh()         |
        return err

In order to resolve the problem, we replace the return err -EBUSY with
-EAGAIN, which means parallel_data is changing, and the caller should call
it again.

v3:
remove retry and just change the return err.
v2:
introduce padata_try_do_parallel() in pcrypt_aead_encrypt and
pcrypt_aead_decrypt to solve the hungtask.

Signed-off-by: Lu Jialin <lujialin4@huawei.com>
Signed-off-by: Guo Zihua <guozihua@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:13 +01:00
WangJinchao
e530cfd7ca padata: Fix refcnt handling in padata_free_shell()
[ Upstream commit 7ddc21e317b360c3444de3023bcc83b85fabae2f ]

In a high-load arm64 environment, the pcrypt_aead01 test in LTP can lead
to system UAF (Use-After-Free) issues. Due to the lengthy analysis of
the pcrypt_aead01 function call, I'll describe the problem scenario
using a simplified model:

Suppose there's a user of padata named `user_function` that adheres to
the padata requirement of calling `padata_free_shell` after `serial()`
has been invoked, as demonstrated in the following code:

```c
struct request {
    struct padata_priv padata;
    struct completion *done;
};

void parallel(struct padata_priv *padata) {
    do_something();
}

void serial(struct padata_priv *padata) {
    struct request *request = container_of(padata,
    				struct request,
				padata);
    complete(request->done);
}

void user_function() {
    DECLARE_COMPLETION(done)
    padata->parallel = parallel;
    padata->serial = serial;
    padata_do_parallel();
    wait_for_completion(&done);
    padata_free_shell();
}
```

In the corresponding padata.c file, there's the following code:

```c
static void padata_serial_worker(struct work_struct *serial_work) {
    ...
    cnt = 0;

    while (!list_empty(&local_list)) {
        ...
        padata->serial(padata);
        cnt++;
    }

    local_bh_enable();

    if (refcount_sub_and_test(cnt, &pd->refcnt))
        padata_free_pd(pd);
}
```

Because of the high system load and the accumulation of unexecuted
softirq at this moment, `local_bh_enable()` in padata takes longer
to execute than usual. Subsequently, when accessing `pd->refcnt`,
`pd` has already been released by `padata_free_shell()`, resulting
in a UAF issue with `pd->refcnt`.

The fix is straightforward: add `refcount_dec_and_test` before calling
`padata_free_pd` in `padata_free_shell`.

Fixes: 07928d9bfc81 ("padata: Remove broken queue flushing")

Signed-off-by: WangJinchao <wangjinchao@xfusion.com>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:04 +01:00
Xiyu Yang
98e84188fd padata: Convert from atomic_t to refcount_t on parallel_data->refcnt
[ Upstream commit d5ee8e750c9449e9849a09ce6fb6b8adeaa66adc ]

refcount_t type and corresponding API can protect refcounters from
accidental underflow and overflow and further use-after-free situations.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Acked-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 7ddc21e317b3 ("padata: Fix refcnt handling in padata_free_shell()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:04 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00