From 2a62beb0f59fa2a417f137f6d82f0878ca136fb7 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Fri, 12 Jan 2024 11:05:28 -0800 Subject: [PATCH] bpf: iter_udp: Retry with a larger batch size without going back to the previous bucket [ Upstream commit 19ca0823f6eaad01d18f664a00550abe912c034c ] The current logic is to use a default size 16 to batch the whole bucket. If it is too small, it will retry with a larger batch size. The current code accidentally does a state->bucket-- before retrying. This goes back to retry with the previous bucket which has already been done. This patch fixed it. It is hard to create a selftest. I added a WARN_ON(state->bucket < 0), forced a particular port to be hashed to the first bucket, created >16 sockets, and observed the for-loop went back to the "-1" bucket. Cc: Aditi Ghag Fixes: c96dac8d369f ("bpf: udp: Implement batching for sockets iterator") Acked-by: Yonghong Song Signed-off-by: Martin KaFai Lau Reviewed-by: Aditi Ghag Link: https://lore.kernel.org/r/20240112190530.3751661-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- net/ipv4/udp.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index bd12a76..a4857c8 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -3192,7 +3192,6 @@ again: /* After allocating a larger batch, retry one more time to grab * the whole bucket. */ - state->bucket--; goto again; } done: -- 2.7.4