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authorPatrick McHardy <kaber@trash.net>2010-04-20 16:02:01 +0200
committerPatrick McHardy <kaber@trash.net>2010-04-20 16:02:01 +0200
commit62910554656cdcd6b6f84a5154c4155aae4ca231 (patch)
treedcf14004f6fd2ef7154362ff948bfeba0f3ea92d /mm/util.c
parent22265a5c3c103cf8c50be62e6c90d045eb649e6d (diff)
parentab9304717f7624c41927f442e6b6d418b2d8b3e4 (diff)
Merge branch 'master' of /repos/git/net-next-2.6
Conflicts: Documentation/feature-removal-schedule.txt net/ipv6/netfilter/ip6t_REJECT.c net/netfilter/xt_limit.c Signed-off-by: Patrick McHardy <kaber@trash.net>
Diffstat (limited to 'mm/util.c')
-rw-r--r--mm/util.c21
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