| Message ID | 2c573564b456327708d175f3124256bc71081bd8.1544445454.git.andreyknvl@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | arm64: untag user pointers passed to the kernel | expand |
diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index b53e1b5d80f4..97467cd2bc59 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -106,6 +106,8 @@ long strncpy_from_user(char *dst, const char __user *src, long count) if (unlikely(count <= 0)) return 0; + src = untagged_addr(src); + max_addr = user_addr_max(); src_addr = (unsigned long)src; if (likely(src_addr < max_addr)) { diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index 60d0bbda8f5e..8b5f56466e00 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -108,6 +108,8 @@ long strnlen_user(const char __user *str, long count) if (unlikely(count <= 0)) return 0; + str = untagged_addr(str); + max_addr = user_addr_max(); src_addr = (unsigned long)str; if (likely(src_addr < max_addr)) {
strncpy_from_user and strnlen_user accept user addresses as arguments, and do not go through the same path as copy_from_user and others, so here we need to handle the case of tagged user addresses separately. Untag user pointers passed to these functions. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> --- lib/strncpy_from_user.c | 2 ++ lib/strnlen_user.c | 2 ++ 2 files changed, 4 insertions(+)