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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-05-17 20:24:04 +0400 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-05-17 20:24:04 +0400 |
| commit | ac1d426e825ab5778995f2f6f053ca2e6b45c622 (patch) | |
| tree | 75b91356ca39463e0112931aa6790802fb1e07a2 /mm/util.c | |
| parent | fda0e18c8a7a3e02747c2b045b4fcd2c920410b9 (diff) | |
| parent | a3685f00652af83f12b63e3b4ef48f29581ba48b (diff) | |
| download | linux-ac1d426e825ab5778995f2f6f053ca2e6b45c622.tar.xz | |
Merge branch 'devel-stable' into devel
Conflicts:
arch/arm/Kconfig
arch/arm/include/asm/system.h
arch/arm/mm/Kconfig
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 |