diff options
| author | Yinghai Lu <yinghai@kernel.org> | 2009-07-01 12:32:18 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-07-02 12:11:12 -0700 |
| commit | 7c5371c403abb29f01bc6cff6c5096abdf2dc524 (patch) | |
| tree | 8c087cac6358dfefa14e6819c4b4dbb4c7326af4 | |
| parent | 43644679a1e80f53e6e0155ab75b1093ba3c0365 (diff) | |
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: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | arch/x86/kernel/e820.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 7271fa33d79..c4ca89d9aaf 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -1383,6 +1383,8 @@ static unsigned long ram_alignment(resource_size_t pos) return 32*1024*1024; } +#define MAX_RESOURCE_SIZE ((resource_size_t)-1) + void __init e820_reserve_resources_late(void) { int i; @@ -1400,17 +1402,19 @@ void __init e820_reserve_resources_late(void) * avoid stolen RAM: */ for (i = 0; i < e820.nr_map; i++) { - struct e820entry *entry = &e820_saved.map[i]; - resource_size_t start, end; + struct e820entry *entry = &e820.map[i]; + u64 start, end; if (entry->type != E820_RAM) continue; start = entry->addr + entry->size; - end = round_up(start, ram_alignment(start)); - if (start == end) + end = round_up(start, ram_alignment(start)) - 1; + if (end > MAX_RESOURCE_SIZE) + end = MAX_RESOURCE_SIZE; + if (start >= end) continue; - reserve_region_with_split(&iomem_resource, start, - end - 1, "RAM buffer"); + reserve_region_with_split(&iomem_resource, start, end, + "RAM buffer"); } } |