xen-project/xen
1
0 Fork 1
mirror of https://github.com/xen-project/xen.git synced 2026-10-28 10:11:27 +01:00
Code Issues Activity

xen/efi: Fix boot from a device without a file system

Browse Source 
When netbooting a unified Xen kernel image (via GRUB chainloader),
the resulting loaded_image->DeviceHandle does not support
SIMPLE_FILE_SYSTEM_PROTOCOL.

Instead of crashing via noreturn PrintErrMesg() in get_parent_handle(),
we defer calling this function until filesystem access is needed.
This way when booting UKI, get_parent_handle() is not called at all.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Suggested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Szymon Acedański <accek@invisiblethingslab.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
This commit is contained in:
Szymon Acedański authored and Andrew Cooper committed 2026-05-28 16:19:16 +01:00
1 parent 6e48abe2f0
commit 880e40b187
3 files changed
+54 -33
Download Patch File Download Diff File Expand all files Collapse all files

No files matched your search

xen/arch/arm/efi/efi-boot.h
+7 -5
View File
@@ -403,7 +403,7 @@ static void __init noreturn efi_arch_post_exit_boot(void)
}
static void __init efi_arch_cfg_file_early(const EFI_LOADED_IMAGE *image,
EFI_FILE_HANDLE dir_handle,
EFI_FILE_HANDLE *dir_handle,
const char *section)
{
union string name;
@@ -419,8 +419,11 @@ static void __init efi_arch_cfg_file_early(const EFI_LOADED_IMAGE *image,
name.s = get_value(&cfg, section, "dtb");
if ( name.s )
{
CHAR16 *fname;
split_string(name.s);
read_file(dir_handle, s2w(&name), &dtbfile, NULL);
ensure_dir_handle(image, dir_handle, &fname);
read_file(*dir_handle, s2w(&name), &dtbfile, NULL);
efi_bs->FreePool(name.w);
}
}
@@ -430,7 +433,7 @@ static void __init efi_arch_cfg_file_early(const EFI_LOADED_IMAGE *image,
}
static void __init efi_arch_cfg_file_late(const EFI_LOADED_IMAGE *image,
EFI_FILE_HANDLE dir_handle,
EFI_FILE_HANDLE *dir_handle,
const char *section)
{
}
@@ -665,8 +668,7 @@ static int __init allocate_module_file(const EFI_LOADED_IMAGE *loaded_image,
file_info->name_len = name_len;
/* Get the file system interface. */
if ( !*dir_handle )
*dir_handle = get_parent_handle(loaded_image, &fname);
ensure_dir_handle(loaded_image, dir_handle, &fname);
/* Load the binary in memory */
read_file(*dir_handle, s2w(&module_name), &module_binary, NULL);
xen/arch/x86/efi/efi-boot.h
+6 -3
View File
@@ -284,13 +284,13 @@ static void __init noreturn efi_arch_post_exit_boot(void)
}
static void __init efi_arch_cfg_file_early(const EFI_LOADED_IMAGE *image,
EFI_FILE_HANDLE dir_handle,
EFI_FILE_HANDLE *dir_handle,
const char *section)
{
}
static void __init efi_arch_cfg_file_late(const EFI_LOADED_IMAGE *image,
EFI_FILE_HANDLE dir_handle,
EFI_FILE_HANDLE *dir_handle,
const char *section)
{
union string name;
@@ -304,9 +304,12 @@ static void __init efi_arch_cfg_file_late(const EFI_LOADED_IMAGE *image,
name.s = get_value(&cfg, "global", "ucode");
if ( name.s )
{
CHAR16 *fname;
microcode_set_module(mbi.mods_count);
split_string(name.s);
read_file(dir_handle, s2w(&name), &ucode, NULL);
ensure_dir_handle(image, dir_handle, &fname);
read_file(*dir_handle, s2w(&name), &ucode, NULL);
efi_bs->FreePool(name.w);
}
}
xen/common/efi/boot.c
+41 -25
View File
@@ -547,6 +547,17 @@ static EFI_FILE_HANDLE __init get_parent_handle(const EFI_LOADED_IMAGE *loaded_i
return dir_handle;
}
static void __init ensure_dir_handle(const EFI_LOADED_IMAGE *loaded_image,
EFI_FILE_HANDLE *dir_handle,
CHAR16 **file_name)
{
if ( *dir_handle )
return;
*dir_handle = get_parent_handle(loaded_image, file_name);
if ( !*dir_handle )
blexit(L"Cannot load files without a usable file system");
}
static CHAR16 *__init point_tail(CHAR16 *fn)
{
CHAR16 *tail = NULL;
@@ -838,12 +849,11 @@ static bool __init read_file(EFI_FILE_HANDLE dir_handle, CHAR16 *name,
if ( !name )
PrintErrMesg(L"No filename", EFI_OUT_OF_RESOURCES);
BUG_ON(!dir_handle);
what = L"Open";
if ( dir_handle )
ret = dir_handle->Open(dir_handle, &FileHandle, name,
EFI_FILE_MODE_READ, 0);
else
ret = EFI_NOT_FOUND;
ret = dir_handle->Open(dir_handle, &FileHandle, name,
EFI_FILE_MODE_READ, 0);
if ( file == &cfg && ret == EFI_NOT_FOUND )
return false;
if ( EFI_ERROR(ret) )
@@ -1514,7 +1524,7 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
if ( use_cfg_file )
{
EFI_FILE_HANDLE dir_handle;
EFI_FILE_HANDLE dir_handle = NULL;
EFI_HANDLE gop_handle;
UINTN depth, cols, rows;
@@ -1526,31 +1536,33 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
gop = efi_get_gop(&gop_handle);
/* Get the file system interface. */
dir_handle = get_parent_handle(loaded_image, &file_name);
/* Read and parse the config file. */
if ( read_section(loaded_image, L"config", &cfg, NULL) )
PrintStr(L"Using builtin config file\r\n");
else if ( !cfg_file_name && file_name )
else
{
CHAR16 *tail;
ensure_dir_handle(loaded_image, &dir_handle, &file_name);
while ( (tail = point_tail(file_name)) != NULL )
if ( !cfg_file_name )
{
wstrcpy(tail, L".cfg");
if ( read_file(dir_handle, file_name, &cfg, NULL) )
break;
*tail = 0;
CHAR16 *tail;
while ( (tail = point_tail(file_name)) != NULL )
{
wstrcpy(tail, L".cfg");
if ( read_file(dir_handle, file_name, &cfg, NULL) )
break;
*tail = 0;
}
if ( !tail )
blexit(L"No configuration file found.");
PrintStr(L"Using configuration file '");
PrintStr(file_name);
PrintStr(L"'\r\n");
}
if ( !tail )
blexit(L"No configuration file found.");
PrintStr(L"Using configuration file '");
PrintStr(file_name);
PrintStr(L"'\r\n");
else if ( !read_file(dir_handle, cfg_file_name, &cfg, NULL) )
blexit(L"Configuration file not found.");
}
else if ( !read_file(dir_handle, cfg_file_name, &cfg, NULL) )
blexit(L"Configuration file not found.");
pre_parse(&cfg);
if ( section.w )
@@ -1567,6 +1579,7 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
if ( !name.s )
break;
free_cfg();
ensure_dir_handle(loaded_image, &dir_handle, &file_name);
if ( !read_file(dir_handle, s2w(&name), &cfg, NULL) )
{
PrintStr(L"Chained configuration file '");
@@ -1578,13 +1591,14 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
efi_bs->FreePool(name.w);
}
efi_arch_cfg_file_early(loaded_image, dir_handle, section.s);
efi_arch_cfg_file_early(loaded_image, &dir_handle, section.s);
option_str = name.s ? split_string(name.s) : NULL;
if ( !read_section(loaded_image, L"kernel", &kernel, option_str) &&
name.s )
{
ensure_dir_handle(loaded_image, &dir_handle, &file_name);
read_file(dir_handle, s2w(&name), &kernel, option_str);
efi_bs->FreePool(name.w);
}
@@ -1599,6 +1613,7 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
name.s = get_value(&cfg, section.s, "ramdisk");
if ( name.s )
{
ensure_dir_handle(loaded_image, &dir_handle, &file_name);
read_file(dir_handle, s2w(&name), &ramdisk, NULL);
efi_bs->FreePool(name.w);
}
@@ -1609,6 +1624,7 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
name.s = get_value(&cfg, section.s, "xsm");
if ( name.s )
{
ensure_dir_handle(loaded_image, &dir_handle, &file_name);
read_file(dir_handle, s2w(&name), &xsm, NULL);
efi_bs->FreePool(name.w);
}
@@ -1634,7 +1650,7 @@ void EFIAPI __init noreturn efi_start(EFI_HANDLE ImageHandle,
}
}
efi_arch_cfg_file_late(loaded_image, dir_handle, section.s);
efi_arch_cfg_file_late(loaded_image, &dir_handle, section.s);
free_cfg();
Reference in new issue
xen-project/xen
Block a user
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.

The note is not visible to the blocked user.