Commit 7c5371c4 authored by Yinghai Lu's avatar Yinghai Lu Committed by Linus Torvalds

x86: add boundary check for 32bit res before expand e820 resource to alignment

fix hang with HIGHMEM_64G and 32bit resource.  According to hpa and
Linus, use (resource_size_t)-1 to fend off big ranges.

Analyzed by hpa
Reported-and-tested-by: default avatarMikael Pettersson <mikpe@it.uu.se>
Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 43644679
...@@ -1383,6 +1383,8 @@ static unsigned long ram_alignment(resource_size_t pos) ...@@ -1383,6 +1383,8 @@ static unsigned long ram_alignment(resource_size_t pos)
return 32*1024*1024; return 32*1024*1024;
} }
#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
void __init e820_reserve_resources_late(void) void __init e820_reserve_resources_late(void)
{ {
int i; int i;
...@@ -1400,17 +1402,19 @@ void __init e820_reserve_resources_late(void) ...@@ -1400,17 +1402,19 @@ void __init e820_reserve_resources_late(void)
* avoid stolen RAM: * avoid stolen RAM:
*/ */
for (i = 0; i < e820.nr_map; i++) { for (i = 0; i < e820.nr_map; i++) {
struct e820entry *entry = &e820_saved.map[i]; struct e820entry *entry = &e820.map[i];
resource_size_t start, end; u64 start, end;
if (entry->type != E820_RAM) if (entry->type != E820_RAM)
continue; continue;
start = entry->addr + entry->size; start = entry->addr + entry->size;
end = round_up(start, ram_alignment(start)); end = round_up(start, ram_alignment(start)) - 1;
if (start == end) if (end > MAX_RESOURCE_SIZE)
end = MAX_RESOURCE_SIZE;
if (start >= end)
continue; continue;
reserve_region_with_split(&iomem_resource, start, reserve_region_with_split(&iomem_resource, start, end,
end - 1, "RAM buffer"); "RAM buffer");
} }
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment