From 00125807e2ed75e32d6c655ffae7fe155e471f9b Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Mon, 21 Sep 2020 17:52:50 +0100 Subject: libfdt: fdt_offset_ptr(): Fix comparison warnings With -Wsign-compare, compilers warn about mismatching signedness in comparisons in fdt_offset_ptr(). This mostly stems from "offset" being passed in as a signed integer, even though the function would not really tolerate negative values. Short of changing the prototype, check that offset is not negative, and use an unsigned type internally. Signed-off-by: Andre Przywara Message-Id: <20200921165303.9115-2-andre.przywara@arm.com> Signed-off-by: David Gibson --- cpukit/dtc/libfdt/fdt.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'cpukit/dtc/libfdt') diff --git a/cpukit/dtc/libfdt/fdt.c b/cpukit/dtc/libfdt/fdt.c index 37b7b93556..04e1e062f2 100644 --- a/cpukit/dtc/libfdt/fdt.c +++ b/cpukit/dtc/libfdt/fdt.c @@ -134,16 +134,20 @@ int fdt_check_header(const void *fdt) const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len) { - unsigned absoffset = offset + fdt_off_dt_struct(fdt); + unsigned int uoffset = offset; + unsigned int absoffset = offset + fdt_off_dt_struct(fdt); + + if (offset < 0) + return NULL; if (!can_assume(VALID_INPUT)) - if ((absoffset < offset) + if ((absoffset < uoffset) || ((absoffset + len) < absoffset) || (absoffset + len) > fdt_totalsize(fdt)) return NULL; if (can_assume(LATEST) || fdt_version(fdt) >= 0x11) - if (((offset + len) < offset) + if (((uoffset + len) < uoffset) || ((offset + len) > fdt_size_dt_struct(fdt))) return NULL; -- cgit v1.2.3