Calls to copy_to_user() or copy_from_user() can fail when copying N
bytes, where N is a constant less than 8, but not 1, 2, 4, or 8,
because 'ret' is not initialized and is only set if the size is 1,
2, 4 or 8, but is tested after the switch statement for any constant
size <= 8. This fixes it by initializing 'ret' to 1, causing the
code to fall through to the __copy_tofrom_user call for sizes other
than 1, 2, 4 or 8.
Signed-off-by: Dave Scidmore <dscidmore@xes-inc.com>
Signed-off-by: Nate Case <ncase@xes-inc.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Those are needed by things like alignment exception fixup handlers
since those can now be triggered by copy_tofrom_user_inatomic.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
"extern inline" generates a warning with -Wmissing-prototypes and I'm
currently working on getting the kernel cleaned up for adding this to
the CFLAGS since it will help us to avoid a nasty class of runtime
errors.
If there are places that really need a forced inline, __always_inline
would be the correct solution.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We have a case where __get_user and __put_user can validly be used
on kernel addresses in interrupt context - namely, the alignment
exception handler, as our get/put_unaligned just do a single access
and rely on the alignment exception handler to fix things up in the
rare cases where the cpu can't handle it in hardware. Thus we can
get alignment exceptions in the network stack at interrupt level.
The alignment exception handler does a __get_user to read the
instruction and blows up in might_sleep().
Since a __get_user on a kernel address won't actually ever sleep,
this makes the might_sleep conditional on the address being less
than PAGE_OFFSET.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch consolidates macros used to generate assembly for
compatibility across different CPUs or configs. A new header,
asm-powerpc/asm-compat.h contains the main compatibility macros. It
uses some preprocessor magic to make the macros suitable both for use
in .S files, and in inline asm in .c files. Headers (bitops.h,
uaccess.h, atomic.h, bug.h) which had their own such compatibility
macros are changed to use asm-compat.h.
ppc_asm.h is now for use in .S files *only*, and a #error enforces
that. As such, we're a lot more careless about namespace pollution
here than in asm-compat.h.
While we're at it, this patch adds a call to the PPC405_ERR77 macro in
futex.h which should have had it already, but didn't.
Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built
for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Change USER/KERNEL_DS so that the merged version of
__strnlen_user can be used which allows us to complete the
removal of arch/ppc64/lib/.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
