diff options
| author | VanGiang Nguyen <vangiang.nguyen@rohde-schwarz.com> | 2024-08-09 06:21:42 +0000 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2024-08-17 13:55:50 +0800 |
| commit | 9a22b2812393d93d84358a760c347c21939029a6 (patch) | |
| tree | c2ecded39607917d856f62aa19ce8d71b31a06d0 | |
| parent | f2f853e7ae4cb0aaf758fa30c07689a8d82680bc (diff) | |
padata: use integer wrap around to prevent deadlock on seq_nr overflow
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>
| -rw-r--r-- | kernel/padata.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/padata.c b/kernel/padata.c index 53f4bc912712..222bccd0c96b 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -404,7 +404,8 @@ void padata_do_serial(struct padata_priv *padata) /* Sort in ascending order of sequence number. */ list_for_each_prev(pos, &reorder->list) { cur = list_entry(pos, struct padata_priv, list); - if (cur->seq_nr < padata->seq_nr) + /* Compare by difference to consider integer wrap around */ + if ((signed int)(cur->seq_nr - padata->seq_nr) < 0) break; } list_add(&padata->list, pos); |