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| author | Hoeun Ryu <hoeun.ryu@gmail.com> | 2017-02-12 07:13:33 +0100 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2017-02-17 01:34:59 +0100 |
| commit | 4fbfeb8bd684d564bddeff1e3723d3d9f99aa5de (patch) | |
| tree | acd71c212dec8ad0f3117b33c5c37ff9e68b1183 /lib | |
| parent | Linux 4.10-rc2 (diff) | |
| download | linux-4fbfeb8bd684d564bddeff1e3723d3d9f99aa5de.tar.xz linux-4fbfeb8bd684d564bddeff1e3723d3d9f99aa5de.zip | |
usercopy: add testcases to check zeroing on failure
During usercopy the destination buffer will be zeroed if copy_from_user()
or get_user() fails. This patch adds testcases for it. The destination
buffer is set with non-zero value before illegal copy_from_user() or
get_user() is executed and the buffer is compared to zero after usercopy
is done.
Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com>
[kees: clarified commit log, dropped second kmalloc]
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/test_user_copy.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c index 0ecef3e4690e..0f86c67d87db 100644 --- a/lib/test_user_copy.c +++ b/lib/test_user_copy.c @@ -69,20 +69,30 @@ static int __init test_user_copy_init(void) "legitimate put_user failed"); /* Invalid usage: none of these should succeed. */ + memset(kmem, 0x5a, PAGE_SIZE); + memset(kmem + PAGE_SIZE, 0, PAGE_SIZE); ret |= test(!copy_from_user(kmem, (char __user *)(kmem + PAGE_SIZE), PAGE_SIZE), "illegal all-kernel copy_from_user passed"); + ret |= test(memcmp(kmem + PAGE_SIZE, kmem, PAGE_SIZE), + "zeroing failure for illegal all-kernel copy_from_user"); + memset(bad_usermem, 0x5A, PAGE_SIZE); ret |= test(!copy_from_user(bad_usermem, (char __user *)kmem, PAGE_SIZE), "illegal reversed copy_from_user passed"); + ret |= test(memcmp(kmem + PAGE_SIZE, bad_usermem, PAGE_SIZE), + "zeroing failure for illegal reversed copy_from_user"); ret |= test(!copy_to_user((char __user *)kmem, kmem + PAGE_SIZE, PAGE_SIZE), "illegal all-kernel copy_to_user passed"); ret |= test(!copy_to_user((char __user *)kmem, bad_usermem, PAGE_SIZE), "illegal reversed copy_to_user passed"); + memset(kmem, 0x5a, PAGE_SIZE); ret |= test(!get_user(value, (unsigned long __user *)kmem), "illegal get_user passed"); + ret |= test(memcmp(kmem + PAGE_SIZE, kmem, sizeof(value)), + "zeroing failure for illegal get_user"); ret |= test(!put_user(value, (unsigned long __user *)kmem), "illegal put_user passed"); |