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| author | VanGiang Nguyen <vangiang.nguyen@rohde-schwarz.com> | 2024-08-09 06:21:42 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-10-04 16:29:56 +0200 |
| commit | 1b8cf11b3ca593a8802a51802cd0c28c38501428 (patch) | |
| tree | 08dd23c8590e48821dcc459eb8ec74e2401150a5 /kernel | |
| parent | 62004f17039dc60cb500337b0792c9f6bbda8e27 (diff) | |
| download | linux-1b8cf11b3ca593a8802a51802cd0c28c38501428.tar.gz linux-1b8cf11b3ca593a8802a51802cd0c28c38501428.tar.bz2 linux-1b8cf11b3ca593a8802a51802cd0c28c38501428.zip | |
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>
Diffstat (limited to 'kernel')
| -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 da788a58d19c..9bf77b58ee08 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); |