5.4-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit b1339be951ad31947ae19bc25cb08769bf255100 ]
Several syzbot soft lockup reports all have in common sock_hash_free()
If a map with a large number of buckets is destroyed, we need to yield the cpu when needed.
Fixes: 75e68e5bf2c7 ("bpf, sockhash: Synchronize delete from bucket list on map free") Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Martin KaFai Lau martin.lau@kernel.org Acked-by: John Fastabend john.fastabend@gmail.com Link: https://lore.kernel.org/bpf/20240906154449.3742932-1-edumazet@google.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/sock_map.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c index f9e9212ff7e5b..42d521443b338 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -945,6 +945,7 @@ static void sock_hash_free(struct bpf_map *map) sock_put(elem->sk); sock_hash_free_elem(htab, elem); } + cond_resched(); }
/* wait for psock readers accessing its map link */