[ Upstream commit c96e8483cb2da6695c8b8d0896fe7ae272a07b54 ]
Gustavo noticed that 'new' can be left uninitialized if 'bios_start' happens to be less or equal to 'entry->addr + entry->size'.
Initialize the variable at the begin of the iteration to the current value of 'bios_start'.
Fixes: 0a46fff2f910 ("x86/boot/compressed/64: Fix boot on machines with broken E820 table") Reported-by: "Gustavo A. R. Silva" gustavo@embeddedor.com Signed-off-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lkml.kernel.org/r/20190826133326.7cxb4vbmiawffv2r@box Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/boot/compressed/pgtable_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index f0537a1f7fc25..76e1edf5bf12a 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -73,7 +73,7 @@ static unsigned long find_trampoline_placement(void)
/* Find the first usable memory region under bios_start. */ for (i = boot_params->e820_entries - 1; i >= 0; i--) { - unsigned long new; + unsigned long new = bios_start;
entry = &boot_params->e820_table[i];