[PATCH 4.9 096/117] Revert "staging: vc04_services: prevent integer overflow in create_pagelist()"

From: Greg Kroah-Hartman
Date: Thu Jun 20 2019 - 14:26:12 EST


From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

This reverts commit cf07331c8827c9e9e0b4274c9b60204c18592241 which was
commit ca641bae6da977d638458e78cd1487b6160a2718 upstream.

Martin writes:
This commit breaks the kernel build because the vchiq_pagelist_info
struct is not defined in v4.9.182.

It was only added in v4.10, in commit
4807f2c0e684e907c501cb96049809d7a957dbc2.

Reported-by: Martin Weinelt <martin@xxxxxxxxxxxxxxx>
Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c | 9 ---------
1 file changed, 9 deletions(-)

--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
@@ -381,18 +381,9 @@ create_pagelist(char __user *buf, size_t
int run, addridx, actual_pages;
unsigned long *need_release;

- if (count >= INT_MAX - PAGE_SIZE)
- return NULL;
-
offset = (unsigned int)buf & (PAGE_SIZE - 1);
num_pages = (count + offset + PAGE_SIZE - 1) / PAGE_SIZE;

- if (num_pages > (SIZE_MAX - sizeof(PAGELIST_T) -
- sizeof(struct vchiq_pagelist_info)) /
- (sizeof(u32) + sizeof(pages[0]) +
- sizeof(struct scatterlist)))
- return NULL;
-
*ppagelist = NULL;

/* Allocate enough storage to hold the page pointers and the page