From 8b021bb956c3c890255d611f3780d3be7638a63a Mon Sep 17 00:00:00 2001 From: Patrick Wildt Date: Mon, 26 Nov 2018 15:58:13 +0100 Subject: [PATCH] fs: fix FAT name extraction The long name apparently can be accumulated using multiple 13-byte slots. Unfortunately we never checked how many we can actually fit in the buffer we are reading to. Signed-off-by: Patrick Wildt --- fs/fat/fat.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/fat/fat.c b/fs/fat/fat.c index e0c076763f..ac8913e719 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -821,6 +821,9 @@ static dir_entry *extract_vfat_name(fat_itr *itr) slot2str((dir_slot *)dent, buf, &idx); + if (n + idx >= sizeof(itr->l_name)) + return NULL; + /* shift accumulated long-name up and copy new part in: */ memmove(itr->l_name + idx, itr->l_name, n); memcpy(itr->l_name, buf, idx); -- 2.39.5