Commit Graph

6 Commits (4718189c4ca83ddaa38a4990bddd1d4196b11933)

Author SHA1 Message Date
Pierre-Clément Tosi 50454658f2 libfdt: Don't mask fdt_get_name() returned error
Return the error code from fdt_get_name() (contained in len when the
result is NULL) instead of masking it with FDT_ERR_BADSTRUCTURE.

Fixes: fda71da26e ("libfdt: Handle failed get_name() on BEGIN_NODE")
Reported-by: Mike McTernan <mikemcternan@google.com>
Signed-off-by: Pierre-Clément Tosi <ptosi@google.com>
Message-Id: <20220729130019.804288-1-ptosi@google.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2022-07-30 13:52:33 +10:00
Pierre-Clément Tosi fda71da26e libfdt: Handle failed get_name() on BEGIN_NODE
Validate the return value of fdt_get_name() as an ill-formed DT, causing
it to fail, could result in fdt_check_full() dereferencing NULL.

fixes: a2def54799 ("libfdt: Check that the root-node name is empty")
Signed-off-by: Pierre-Clément Tosi <ptosi@google.com>
Message-Id: <20220714083848.958492-1-ptosi@google.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2022-07-26 21:46:18 +10:00
Simon Glass a2def54799 libfdt: Check that the root-node name is empty
The root node is supposed to have an empty name, but at present this is
not checked. The behaviour of such a tree is not well defined. Most
software rightly assumes that the root node is at offset 0 and does not
check the name. This oddity was discovered as part of a security
investigation into U-Boot verified boot.

Add a check for this to fdt_check_full().

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Arie Haenel <arie.haenel@intel.com>
Reported-by: Julien Lenoir <julien.lenoir@intel.com>
Message-Id: <20210323010410.3222701-2-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-03-23 12:13:06 +11:00
Simon Glass 4ca61f84dc libfdt: Check that there is only one root node
At present it is possible to have two root nodes and even access nodes
in the 'second' root. Such trees should not be considered valid. This
was discovered as part of a security investigation into U-Boot verified
boot.

Add a check for this to fdt_check_full().

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Arie Haenel <arie.haenel@intel.com>
Reported-by: Julien Lenoir <julien.lenoir@intel.com>
Message-Id: <20210323000926.3210733-1-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-03-23 11:56:34 +11:00
Patrick Oppenlander 3e3138b4a9 libfdt: fix fdt_check_full buffer overrun
fdt_check_header assumes that its argument points to a complete header
and can read data beyond the FDT_V1_SIZE bytes which fdt_check_full
can provide.

fdt_header_size can safely return a header size with FDT_V1_SIZE bytes
available and will return a usable value even for a corrupted header.

Signed-off-by: Patrick Oppenlander <patrick.oppenlander@gmail.com>
Message-Id: <20200709041451.338548-1-patrick.oppenlander@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-07-10 19:55:36 +10:00
Simon Glass 0f61c72ded libfdt: Allow exclusion of fdt_check_full()
This function is used to perform a full check of the device tree. Allow
it to be excluded if all assumptions are enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200220214557.176528-9-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-24 13:38:44 +11:00