5.4-stable review patch. If anyone has any objections, please let me know.
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From: Jakub Kicinski kuba@kernel.org
[ Upstream commit 0de6a472c3b38432b2f184bd64eb70d9ea36d107 ]
Commit 51183d233b5a ("net/neighbor: Update neigh_dump_info for strict data checking") added strict checking. The err variable is not cleared, so if we find no table to dump we will return the validation error even if user did not want strict checking.
I think the only way to hit this is to send an buggy request, and ask for a table which doesn't exist, so there's no point treating this as a real fix. I only noticed it because a syzbot repro depended on it to trigger another bug.
Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20241115003221.733593-1-kuba@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/neighbour.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index e571007d083cc..4dfe17f1a76aa 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -2734,6 +2734,7 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb) err = neigh_valid_dump_req(nlh, cb->strict_check, &filter, cb->extack); if (err < 0 && cb->strict_check) return err; + err = 0;
s_t = cb->args[0];