uaccess: reimplement probe_kernel_address() using probe_kernel_read()
probe_kernel_address() is basically the same as the (later added)
probe_kernel_read().
The return value on EFAULT is a bit different: probe_kernel_address()
returns number-of-bytes-not-copied whereas probe_kernel_read() returns
-EFAULT. All callers have been checked, none cared.
probe_kernel_read() can be overridden by the architecture whereas
probe_kernel_address() cannot. parisc, blackfin and um do this, to insert
additional checking. Hence this patch possibly fixes obscure bugs,
although there are only two probe_kernel_address() callsites outside
arch/.
My first attempt involved removing probe_kernel_address() entirely and
converting all callsites to use probe_kernel_read() directly, but that got
tiresome.
This patch shrinks mm/slab_common.o by 218 bytes. For a single
probe_kernel_address() callsite.
Cc: Steven Miao <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
4 files changed
