diff options
author | Robert Richter <robert.richter@amd.com> | 2010-04-23 14:30:22 +0200 |
---|---|---|
committer | Robert Richter <robert.richter@amd.com> | 2010-04-23 14:30:22 +0200 |
commit | a36bf32e9e8a86f291f746b7f8292e042ee04a46 (patch) | |
tree | c5c999baa4c214218e3adea9b336cbd9f23950ad /mm/util.c | |
parent | bc078e4eab65f11bbaeed380593ab8151b30d703 (diff) | |
parent | 01bf0b64579ead8a82e7cfc32ae44bc667e7ad0f (diff) |
Merge commit 'v2.6.34-rc5' into oprofile/core
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 834db7be240f..f5712e8964be 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 |