diff options
| author | Jonathan Corbet <corbet@lwn.net> | 2019-06-14 14:18:53 -0600 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2019-06-14 14:18:53 -0600 |
| commit | 8afecfb0ec961e37e61b2d19c4fa71617a9482de (patch) | |
| tree | c43ea51a47b1e76b762caa4c1b0c356249e5e874 /drivers/misc/lkdtm/usercopy.c | |
| parent | ce1a5ea18ef9bf4c62c75abe7c540a29264ec988 (diff) | |
| parent | d1fdb6d8f6a4109a4263176c84b899076a5f8008 (diff) | |
Merge tag 'v5.2-rc4' into mauro
We need to pick up post-rc1 changes to various document files so they don't
get lost in Mauro's massive RST conversion push.
Diffstat (limited to 'drivers/misc/lkdtm/usercopy.c')
| -rw-r--r-- | drivers/misc/lkdtm/usercopy.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c index d5a0e7f1813b..e172719dd86d 100644 --- a/drivers/misc/lkdtm/usercopy.c +++ b/drivers/misc/lkdtm/usercopy.c @@ -324,14 +324,16 @@ free_user: void lkdtm_USERCOPY_KERNEL_DS(void) { - char __user *user_ptr = (char __user *)ERR_PTR(-EINVAL); + char __user *user_ptr = + (char __user *)(0xFUL << (sizeof(unsigned long) * 8 - 4)); mm_segment_t old_fs = get_fs(); char buf[10] = {0}; - pr_info("attempting copy_to_user on unmapped kernel address\n"); + pr_info("attempting copy_to_user() to noncanonical address: %px\n", + user_ptr); set_fs(KERNEL_DS); - if (copy_to_user(user_ptr, buf, sizeof(buf))) - pr_info("copy_to_user un unmapped kernel address failed\n"); + if (copy_to_user(user_ptr, buf, sizeof(buf)) == 0) + pr_err("copy_to_user() to noncanonical address succeeded!?\n"); set_fs(old_fs); } |