From: Matthias Brugger Date: Thu, 5 Sep 2019 08:48:48 +0000 (+0200) Subject: libfdt: Allow #size-cells of 0 X-Git-Url: http://git.dujemihanovic.xyz/login.html?a=commitdiff_plain;h=8076fc298ee1004cfbd9f9f4882931aff1ffda06;p=u-boot.git libfdt: Allow #size-cells of 0 The commit "libfdt: fdt_address_cells() and fdt_size_cells()" introduced a bug as it consolidated code between the helpers for getting be 0, and is frequently found so in practice for /cpus. IEEE1275 only requires implementations to handle 1..4 for #address-cells, although one could make a case for #address-cells == #size-cells == 0 being used to represent a bridge with a single port. While we're there, it's not totally obvious that the existing implicit cast of a u32 to int will give the correct results according to strict C, although it does work in practice. Straighten that up to cast only after we've made our range checks. This is based on upstream commit: b8d6eca ("libfdt: Allow #size-cells of 0") but misses the test cases,as we don't implement them in U-Boot. Signed-off-by: Matthias Brugger --- diff --git a/scripts/dtc/libfdt/fdt_addresses.c b/scripts/dtc/libfdt/fdt_addresses.c index f13a87dfa0..788c143113 100644 --- a/scripts/dtc/libfdt/fdt_addresses.c +++ b/scripts/dtc/libfdt/fdt_addresses.c @@ -59,7 +59,7 @@ static int fdt_cells(const void *fdt, int nodeoffset, const char *name) { const fdt32_t *c; - int val; + uint32_t val; int len; c = fdt_getprop(fdt, nodeoffset, name, &len); @@ -70,10 +70,10 @@ static int fdt_cells(const void *fdt, int nodeoffset, const char *name) return -FDT_ERR_BADNCELLS; val = fdt32_to_cpu(*c); - if ((val <= 0) || (val > FDT_MAX_NCELLS)) + if (val > FDT_MAX_NCELLS) return -FDT_ERR_BADNCELLS; - return val; + return (int)val; } int fdt_address_cells(const void *fdt, int nodeoffset) @@ -81,6 +81,8 @@ int fdt_address_cells(const void *fdt, int nodeoffset) int val; val = fdt_cells(fdt, nodeoffset, "#address-cells"); + if (val == 0) + return -FDT_ERR_BADNCELLS; if (val == -FDT_ERR_NOTFOUND) return 2; return val;