diff options
author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2014-10-29 19:09:32 +0300 |
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committer | Grant Likely <grant.likely@linaro.org> | 2014-11-04 19:43:10 +0300 |
commit | 8cccffc52694938fc88f3d90bc7fed8460e27191 (patch) | |
tree | 76ea435917e5cfd97859a813103a3aaa52ae5124 /drivers/of | |
parent | 50ba08f301a1b0310775deeed00c9b24ba75fe8a (diff) | |
download | linux-8cccffc52694938fc88f3d90bc7fed8460e27191.tar.xz |
of: check for size < 0 after rounding in early_init_dt_add_memory_arch
Memory regions passed to early_init_dt_add_memory_arch() are rounded to
PAGE_SIZE by subtracting the size of the leading fractional page from
the 'size' argument. However, size being a u64 type, if its value is
sufficiently small, the subtraction wraps around and produces a bogus
value, potentially leading to crashes.
Fix this by ignoring the memory range in such cases.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Diffstat (limited to 'drivers/of')
-rw-r--r-- | drivers/of/fdt.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 535124670257..83a8e1154602 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -928,6 +928,11 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) const u64 phys_offset = __pa(PAGE_OFFSET); if (!PAGE_ALIGNED(base)) { + if (size < PAGE_SIZE - (base & ~PAGE_MASK)) { + pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", + base, base + size); + return; + } size -= PAGE_SIZE - (base & ~PAGE_MASK); base = PAGE_ALIGN(base); } |