Forum | Documentation | Website | Blog

Skip to content
Snippets Groups Projects
Commit 1d3fb6bb authored by H. Peter Anvin's avatar H. Peter Anvin Committed by Greg Kroah-Hartman
Browse files

compat: Make compat_alloc_user_space() incorporate the access_ok()

commit c41d68a5

 upstream.

compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area.  A missing call could
introduce problems on some architectures.

This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.

This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures.  This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.

Reported-by: default avatarBen Hawkes <hawkes@sota.gen.nz>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
Acked-by: default avatarBenjamin Herrenschmidt <benh@...>
parent 18023624
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment