From 1eb7682f845ac9e9bf9ae35bbfb3bad5dacbd91d Mon Sep 17 00:00:00 2001 From: Mark Adler Date: Mon, 8 Aug 2022 10:50:09 -0700 Subject: [PATCH] Fix extra field processing bug that dereferences NULL state->head. The recent commit to fix a gzip header extra field processing bug introduced the new bug fixed here. --- inflate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/inflate.c b/inflate.c index 7a72897..2a3c4fe 100644 --- a/inflate.c +++ b/inflate.c @@ -763,10 +763,10 @@ int flush; copy = state->length; if (copy > have) copy = have; if (copy) { - len = state->head->extra_len - state->length; if (state->head != Z_NULL && state->head->extra != Z_NULL && - len < state->head->extra_max) { + (len = state->head->extra_len - state->length) < + state->head->extra_max) { zmemcpy(state->head->extra + len, next, len + copy > state->head->extra_max ? state->head->extra_max - len : copy); -- 2.35.3