From: Mikulas Patocka <mpatocka@redhat.com> stable inclusion from stable-v5.4.274 commit e7d4cff57c3c43fdd72342c78d4138f509c7416e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CC CVE: CVE-2024-35805 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 6e7132ed3c07bd8a6ce3db4bb307ef2852b322dc ] There was reported lockup when we exit a snapshot with many exceptions. Fix this by adding "cond_resched" to the loop that frees the exceptions. Reported-by: John Pittman <jpittman@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> --- drivers/md/dm-snap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 41735a25d50a..de73fe79640f 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -685,8 +685,10 @@ static void dm_exception_table_exit(struct dm_exception_table *et, for (i = 0; i < size; i++) { slot = et->table + i; - hlist_bl_for_each_entry_safe(ex, pos, n, slot, hash_list) + hlist_bl_for_each_entry_safe(ex, pos, n, slot, hash_list) { kmem_cache_free(mem, ex); + cond_resched(); + } } vfree(et->table); -- 2.31.1