[PATCH 0/4] return EINVAL for illegal user memory range

Wupeng Ma
2022-12-05T03:41:33Z

From: Ma Wupeng <mawupeng1@huawei.com>

While testing mlock, we have a problem if the len of mlock is ULONG_MAX.
The return value of mlock is zero. But nothing will be locked since the
len in do_mlock overflows to zero due to the following code in mlock:

len = PAGE_ALIGN(len + (offset_in_page(start)));

However this problem appear in multiple syscalls.

Since TASK_SIZE is the maximum user space address. The start or len of
mlock shouldn't be bigger than this. Function access_ok can be used to
check this issue, so return -EINVAL if bigger.

Ma Wupeng (4):
mm/mlock: return EINVAL for illegal user memory range in mlock
mm/mempolicy: return EINVAL for illegal user memory range for
set_mempolicy_home_node
mm/mempolicy: return EINVAL for illegal user memory range for mbind
mm/msync: return EINVAL for illegal user memory range for msync

mm/mempolicy.c | 7 +++++++
mm/mlock.c | 6 ++++++
mm/msync.c | 2 ++
3 files changed, 15 insertions(+)

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2.25.1