[PATCH] ofmem: restrict ofmem_claim() allocations to RAM size
As OFMEM memory ranges don't provide an explicit upper limit, we must manually check that CIF claim calls lie within a valid maxmimum range if attempting to allocate a specific address. Since the claim method provides a 1:1 mapping between physical and virtual addresses, the valid maximum address is therefore equivalent to the machine RAM size. This fixes booting yaboot 1.3.17 which implements a top-down search using claim to find the next free memory region to locate its heap. Without this fix we blindly accept a claim for physical addresses far above the available RAM which fails silently when we try to use the mapping later. Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> --- libopenbios/ofmem_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libopenbios/ofmem_common.c b/libopenbios/ofmem_common.c index 217bd9b..fc19d27 100644 --- a/libopenbios/ofmem_common.c +++ b/libopenbios/ofmem_common.c @@ -623,7 +623,7 @@ ucell ofmem_claim( ucell addr, ucell size, ucell align ) virt = phys = 0; if( !align ) { if( is_free(addr, size, ofmem->virt_range) && - is_free(addr, size, ofmem->phys_range) ) { + is_free(addr, size, ofmem->phys_range) && addr < get_ram_size() ) { ofmem_claim_phys_( addr, size, 0, 0, 0, 0 ); ofmem_claim_virt_( addr, size, 0, 0, 0, 0 ); virt = phys = addr; -- 2.11.0
On 13/02/18 22:41, Mark Cave-Ayland wrote:
As OFMEM memory ranges don't provide an explicit upper limit, we must manually check that CIF claim calls lie within a valid maxmimum range if attempting to allocate a specific address. Since the claim method provides a 1:1 mapping between physical and virtual addresses, the valid maximum address is therefore equivalent to the machine RAM size.
This fixes booting yaboot 1.3.17 which implements a top-down search using claim to find the next free memory region to locate its heap. Without this fix we blindly accept a claim for physical addresses far above the available RAM which fails silently when we try to use the mapping later.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> --- libopenbios/ofmem_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libopenbios/ofmem_common.c b/libopenbios/ofmem_common.c index 217bd9b..fc19d27 100644 --- a/libopenbios/ofmem_common.c +++ b/libopenbios/ofmem_common.c @@ -623,7 +623,7 @@ ucell ofmem_claim( ucell addr, ucell size, ucell align ) virt = phys = 0; if( !align ) { if( is_free(addr, size, ofmem->virt_range) && - is_free(addr, size, ofmem->phys_range) ) { + is_free(addr, size, ofmem->phys_range) && addr < get_ram_size() ) { ofmem_claim_phys_( addr, size, 0, 0, 0, 0 ); ofmem_claim_virt_( addr, size, 0, 0, 0, 0 ); virt = phys = addr;
Applied to master. ATB, Mark.
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Mark Cave-Ayland