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| author | Ingo Molnar <mingo@elte.hu> | 2010-04-15 09:35:24 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-04-15 09:36:16 +0200 |
| commit | b257c14ceb1194a6181144210056d38f22127189 (patch) | |
| tree | c803925f1d5bf2237e7495d306bf43929df0c952 /mm/util.c | |
| parent | 371fd7e7a56a5c136d31aa980011bd2f131c3ef5 (diff) | |
| parent | 2ba3abd8186f24c7fb418927025b4e2120e3a362 (diff) | |
| download | linux-b257c14ceb1194a6181144210056d38f22127189.tar.gz | |
Merge branch 'linus' into sched/core
Merge reason: merge the latest fixes, update to -rc4.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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 |