aboutsummaryrefslogtreecommitdiffstats
path: root/mm/util.c
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2010-04-11 02:44:30 -0700
committerDavid S. Miller <davem@davemloft.net>2010-04-11 02:44:30 -0700
commit4a1032faac94ebbf647460ae3e06fc21146eb280 (patch)
tree7f31b97beb0406faa1523e619289ad0ab07c9787 /mm/util.c
parentae4e8d63b5619d4d95f1d2bfa2b836caa6e62d06 (diff)
parent0eddb519b9127c73d53db4bf3ec1d45b13f844d1 (diff)
downloadkernel_samsung_smdk4412-4a1032faac94ebbf647460ae3e06fc21146eb280.zip
kernel_samsung_smdk4412-4a1032faac94ebbf647460ae3e06fc21146eb280.tar.gz
kernel_samsung_smdk4412-4a1032faac94ebbf647460ae3e06fc21146eb280.tar.bz2
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
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 834db7b..f5712e8 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