From: VanGiang Nguyen vangiang.nguyen@rohde-schwarz.com
stable inclusion from stable-v6.6.54 commit 1b8cf11b3ca593a8802a51802cd0c28c38501428 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYQSB CVE: CVE-2024-47739
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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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 Signed-off-by: Cheng Yu serein.chengyu@huawei.com --- kernel/padata.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/padata.c b/kernel/padata.c index 29545dd6dd53..8f0af2c09e17 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);