This new function implements a complete and thorough check of an fdt blob's
structure. Given a buffer containing an fdt, it should return 0 only if
the fdt within is structurally sound in all regards. It doesn't check
anything about the blob's contents (i.e. the actual values of the nodes and
properties), of course.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
We have a couple of places within libfdt and its tests where we need to
find the size of the header, based on the version. Add a helper function
for it.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
fdt_num_mem_rsv() and fdt_get_mem_rsv() currently don't sanity check their
parameters, or the memory reserve section offset in the header. That means
that on a corrupted blob they could access outside of the range of memory
that they should.
This improves their safety checking, meaning they shouldn't access outside
the blob's bounds, even if its contents are badly corrupted.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
fdt_getprop_by_offset() doesn't check for errors from fdt_string() - after
all, until very recently it couldn't fail. Now it can, so we need to
propagate errors up to the caller.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
fdt_string() is used to retrieve strings from a DT blob's strings section.
It's rarely used directly, but is widely used internally.
However, it doesn't do any bounds checking, which means in the case of a
corrupted blob it could access bad memory, which libfdt is supposed to
avoid.
This write a safe alternative to fdt_string, fdt_get_string(). It checks
both that the given offset is within the string section and that the string
it points to is properly \0 terminated within the section. It also returns
the string's length as a convenience (since it needs to determine to do the
checks anyway).
fdt_string() is rewritten in terms of fdt_get_string() for compatibility.
Most of the diff here is actually testing infrastructure.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Currently fdt_check_header() performs only some rudimentary checks, which
is not really what the name suggests. This strengthens fdt_check_header()
to check as much about the blob as is possible from the header alone: as
well as checking the magic number and version, it checks that the total
size is sane, and that all the sub-blocks within the blob lie within the
total size.
* This broadens the meaning of FDT_ERR_TRUNCATED to cover all sorts of
improperly terminated blocks as well as just a structure block without
FDT_END.
* This makes fdt_check_header() only succeed on "complete" blobs, not
in-progress sequential write blobs. The only reason this didn't fail
before was that this function used to be called by many RO functions
which are supposed to also work on incomplete SW blobs.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
When creating a tree with the sequential write functions, certain things
have to be done in a certain order. You must create the memory reserve map
and only then can you create the actual tree structure.
The -FDT_ERR_BADSTATE return code is for if you try to do things out of
order. However, we weren't checking that very thoroughly, so it was
possible to generate a corrupted blob if, for example, you started calling
fdt_begin_node() etc. before calling fdt_finish_reservemap().
This makes the state checking more thorough disallow that.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
Many of the libfdt entry points call some sort of sanity check function
before doing anything else. These need to do slightly different things for
the various classes of functions.
The read-only version is shared with the exported fdt_check_header(), which
limits us a bit in how we can improve it. For that reason split the two
functions apart (though the exported one just calls the ro one for now).
We also rename the functions for more consistency - they're all named
fdt_XX_probe_() where the XX indicates which class of functions they're
for. "probe" is a better "term" than the previous check, since they really
only do minimal validation.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
This can be useful in particular in the kernel when booting on systems
with FDT-emitting firmware that is out of date. Releases of kexec-tools
on ppc64 prior to the end of 2014 are notable examples of such.
Signed-off-by: Nathan Whitehorn <nwhitehorn@freebsd.org>
[dwg: Some whitespace cleanups]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Prior the Mac OS 10.7, the function strnlen() was not available. This patch
implements strnlen() on Mac OS X versions that are below 10.7.
Signed-off-by: John Arbuckle <programmingkidx@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
In a lot of places libfdt uses a leading _ character to mark an identifier
as "internal" (not part of the published libfdt API). This is a bad idea,
because identifiers with a leading _ are generally reserved by the C
library or system. It's particularly dangerous for libfdt, because it's
designed to be able to be integrated into lots of different environments.
In some cases the leading _ has no purpose, so we simply drop it. In most
cases we move it to the end, as our new convention for marking internal
identifiers.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
A comment in tests/stringlist.c refers to fdt_get_string(), which is not a
function that exists. From the content, it's supposed to be referring to
fdt_getprop_string().
A comment in libfdt.h has an extraneous space in a function name.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
In some cases you need to add a property but the contents of it
are not known at creation time, merely the extend of it.
This method allows you to create a property of a given size (filled
with garbage) while a pointer to the property data will be provided.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[dwg: Corrected commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The existing function to add a new property to a tree being built requires
that the entire contents of the new property be passed in. For some
applications it is more convenient to be able to add the property contents
later, perhaps by reading from a file. This avoids double-buffering of the
contents.
Add a new function to support this and adjust the existing fdt_property() to
use it.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There are a few places where libfdt.h cannot be used as is with swig:
- macros like fdt_totalsize() have to be defined as C declarations
- fdt_offset_ptr() and fdt_getprop_namelen() need special treatment due to
a TODO in the wrapper for fdt_getprop(). However they are not useful to
Python so can be removed
Add #ifdefs to work around these problem.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The default libfdt_env.h (for POSIXish userland builds) supports sparse
checking. It has a couple of helper macros, __force and __bitwise which
expand the relevant sparse attributes to enable checking for incorrect
or missing endian conversions.
Those are bad names: for one, leading underscores are supposed to be
reserved for the system libraries, and worse, some systems (including
RHEL7) do define those names already.
So change them to FDT_FORCE and FDT_BITWISE which are far less likely to
have collisions.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Device trees can contain empty (zero length) properties, which are often
used as boolean flags. These can already be created using fdt_setprop()
passing a length of zero and a pointer which is ignored. It is safe to
pass NULL, but that may not be obvious from the interface. To make it
clearer, add an fdt_setprop_empty() helper macro.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The standard way of setting an empty property using libfdt is:
fdt_setprop(fdt, nodeoffset, propname, NULL, 0);
However, the implementation of this includes an unconditional:
memcpy(prop->data, NULL, 0);
Which although it will be a no-op (which is what we want) on many platforms
is technically undefined behaviour. Correct this, so that when passing
a 0 length, passing a NULL pointer as the value to fdt_setprop() is
definitely safe. This should quiet static checkers which complain about
this.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Some error values were missing from the table which meant that they could
not be translated by fdt_strerror().
Signed-off-by: Benjamin Fair <b-fair@ti.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The BADPHANDLE error was missing a string, leading to an <unknown error>
string being returned if you were to call fdt_strerror.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The device tree overlays are a good way to deal with user-modifyable
boards or boards with some kind of an expansion mechanism where we can
easily plug new board in (like the BBB, the Raspberry Pi or the CHIP).
Add a new function to merge overlays with a base device tree.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
So far, the BADPHANDLE error was only used for incorrect phandle values.
Extend that meaning to an improperly formatted phandle property.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add a few new error codes to report the failure conditions we might
encounter in the overlay application code:
- FDT_ERR_BADOVERLAY, when an overlay cannot be parsed, even though its
structure is correct
- FDT_ERR_NOPHANDLES, when we ran out of available phandles and we
cannot use a new phandle without either using an invalid one (-1 or
0), or one already used.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add a function to modify inplace only a portion of a property..
This is especially useful when the property is an array of values, and you
want to update one of them without changing the DT size.
Acked-by: Simon Glass <sjg@chromium.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
[dwg: Remove unnecessary unsigned qualifier, correct a comment]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Implement a macro based on fdt_first_property_offset and
fdt_next_property_offset that provides a convenience to iterate over all
the properties of a given node.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Simon Glass <sjg@chromium.org>
[dwg: Removed a stray trailing blank line]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The fdt_for_each_subnode() iterator macro provided by this patch can be
used to iterate over a device tree node's subnodes. At each iteration a
loop variable will be set to the next subnode.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There are a few places with a space before a tab in this file. Fix them.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Because fdt_stringlist_contains() returns 1 or 0,
fdt_node_check_compatible() can just return the inverted value.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Using pointer arithmetic to generate a pointer outside a known object is,
technically, undefined behaviour in C. Unfortunately, we were using that
in fdt_offset_ptr() to detect overflows.
To fix this we need to do our bounds / overflow checking on the offsets
before constructing pointers from them.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch catches the conditions where:
- 'splicepoint' is set to a point outside of [ fdt, fdt_totalsize(fdt) )
- 'newlen' is negative, or 'splicepoint' plus 'newlen' results in overflow
Either of these cases can be caused by math which overflows in calling
functions, or by sizes specified through dynamic means.
Signed-off-by: Courtney Cavin <courtney.cavin@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
->fail_addr and ->addr can be updated no matter the result of
parent->_erase(), we just need to remove the code doing the same thing
in mtd_erase_callback() to avoid adjusting those fields twice.
Note that this can be done because all MTD users have been converted to
not pass an erase_info->callback() and are thus only taking the
->addr_fail and ->addr fields into account after part_erase() has
returned.
While we're at it, get rid of the erase_info->mtd field which was only
needed to let mtd_erase_callback() get the partition device back.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
None of the mtd->_erase() implementations work in an asynchronous manner,
so let's simplify MTD users that call mtd_erase(). All they need to do
is check the value returned by mtd_erase() and assume that != 0 means
failure.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
