From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Daniel Axtens Date: Fri, 22 Jan 2021 18:13:56 +1100 Subject: [PATCH] fs/hfsplus: Don't fetch a key beyond the end of the node Otherwise you get a wild pointer, leading to a bunch of invalid reads. Check it falls inside the given node. Signed-off-by: Daniel Axtens Reviewed-by: Daniel Kiper --- grub-core/fs/hfsplus.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/grub-core/fs/hfsplus.c b/grub-core/fs/hfsplus.c index 03a33ea24..423f4b956 100644 --- a/grub-core/fs/hfsplus.c +++ b/grub-core/fs/hfsplus.c @@ -635,6 +635,10 @@ grub_hfsplus_btree_search (struct grub_hfsplus_btree *btree, pointer = ((char *) currkey + grub_be_to_cpu16 (currkey->keylen) + 2); + + if ((char *) pointer > node + btree->nodesize - 2) + return grub_error (GRUB_ERR_BAD_FS, "HFS+ key beyond end of node"); + currnode = grub_be_to_cpu32 (grub_get_unaligned32 (pointer)); match = 1; }