| Message ID | 20230203132213.11758-1-aagusev@ispras.ru |
|---|---|
| State | New |
| Headers | show |
| Series | efi: fix potential NULL deref in efi_mem_reserve_persistent | expand |
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index a2b0cbc8741c..48d30c806d94 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1007,6 +1007,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) /* first try to find a slot in an existing linked list entry */ for (prsv = efi_memreserve_root->next; prsv; ) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); + if (!rsv) + break; index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { rsv->entry[index].base = addr;
When iterating on a linked list, a result of memremap is dereferenced without checking it for NULL. This patch adds a check that falls back on allocating a new page in case memremap doesn't succeed. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 18df7577adae ("efi/memreserve: deal with memreserve entries in unmapped memory") Signed-off-by: Anton Gusev <aagusev@ispras.ru> --- drivers/firmware/efi/efi.c | 2 ++ 1 file changed, 2 insertions(+)