Hi,

all stable release queues from v4.9.y up to v5.4.y have boot stall problems. The culprit is the backport of commit d7ea0d9df2a6 ("net: remove two BUG() from skb_checksum_help()"), specifically the following code.

diff --git a/net/core/dev.c b/net/core/dev.c index 47468fc5d0c9..d725ca4d4455 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2518,11 +2518,15 @@ int skb_checksum_help(struct sk_buff *skb) ... - BUG_ON(offset >= skb_headlen(skb)); + ret = -EINVAL; ^^^^^^^^^^^^^^ + if (WARN_ON_ONCE(offset >= skb_headlen(skb))) + goto out; +

While that works fine in the upstream kernel since ret is subsequently always overwritten, that is not the case in older kernels. In those, the function now always returns -EINVAL.

Guenter