diff options
| author | H. Peter Anvin <hpa@zytor.com> | 2010-05-08 14:59:58 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2010-05-08 14:59:58 -0700 |
| commit | d7be0ce6afb1df60bc786f57410407ceae92b994 (patch) | |
| tree | 5e91acfc12c833531ad3320f274e0cd96a129973 /mm/util.c | |
| parent | e08cae4181af9483b04ecfac48f01c8e5a5f27bf (diff) | |
| parent | 66f41d4c5c8a5deed66fdcc84509376c9a0bf9d8 (diff) | |
| download | kernel-crypto-d7be0ce6afb1df60bc786f57410407ceae92b994.tar.gz kernel-crypto-d7be0ce6afb1df60bc786f57410407ceae92b994.tar.xz kernel-crypto-d7be0ce6afb1df60bc786f57410407ceae92b994.zip | |
Merge commit 'v2.6.34-rc6' into x86/cpu
Diffstat (limited to 'mm/util.c')
| -rw-r--r-- | mm/util.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/mm/util.c b/mm/util.c index 834db7be240..f5712e8964b 100644 --- a/mm/util.c +++ b/mm/util.c @@ -186,6 +186,27 @@ void kzfree(const void *p) } EXPORT_SYMBOL(kzfree); +int kern_ptr_validate(const void *ptr, unsigned long size) +{ + unsigned long addr = (unsigned long)ptr; + unsigned long min_addr = PAGE_OFFSET; + unsigned long align_mask = sizeof(void *) - 1; + + if (unlikely(addr < min_addr)) + goto out; + if (unlikely(addr > (unsigned long)high_memory - size)) + goto out; + if (unlikely(addr & align_mask)) + goto out; + if (unlikely(!kern_addr_valid(addr))) + goto out; + if (unlikely(!kern_addr_valid(addr + size - 1))) + goto out; + return 1; +out: + return 0; +} + /* * strndup_user - duplicate an existing string from user space * @s: The string to duplicate |