From dadb57abc37499f565b23933dbf49b435c3ba8af Mon Sep 17 00:00:00 2001 From: Jeffrey Hugo Date: Mon, 29 Aug 2016 14:38:51 -0600 Subject: efi/libstub: Allocate headspace in efi_get_memory_map() efi_get_memory_map() allocates a buffer to store the memory map that it retrieves. This buffer may need to be reused by the client after ExitBootServices() is called, at which point allocations are not longer permitted. To support this usecase, provide the allocated buffer size back to the client, and allocate some additional headroom to account for any reasonable growth in the map that is likely to happen between the call to efi_get_memory_map() and the client reusing the buffer. Signed-off-by: Jeffrey Hugo Cc: Ard Biesheuvel Cc: Mark Rutland Cc: Leif Lindholm Cc: Ingo Molnar Cc: Signed-off-by: Matt Fleming --- arch/x86/boot/compressed/eboot.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'arch/x86/boot') diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index ff574da..c5b7c7b 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1008,7 +1008,7 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle, bool is64) { struct efi_info *efi = &boot_params->efi_info; - unsigned long map_sz, key, desc_size; + unsigned long map_sz, key, desc_size, buff_size; efi_memory_desc_t *mem_map; struct setup_data *e820ext; const char *signature; @@ -1019,14 +1019,20 @@ static efi_status_t exit_boot(struct boot_params *boot_params, bool called_exit = false; u8 nr_entries; int i; - - nr_desc = 0; - e820ext = NULL; - e820ext_size = 0; + struct efi_boot_memmap map; + + nr_desc = 0; + e820ext = NULL; + e820ext_size = 0; + map.map = &mem_map; + map.map_size = &map_sz; + map.desc_size = &desc_size; + map.desc_ver = &desc_version; + map.key_ptr = &key; + map.buff_size = &buff_size; get_map: - status = efi_get_memory_map(sys_table, &mem_map, &map_sz, &desc_size, - &desc_version, &key); + status = efi_get_memory_map(sys_table, &map); if (status != EFI_SUCCESS) return status; -- cgit v1.1