From: Matt Fleming <matt.fleming@intel.com>
Date: Thu, 10 Apr 2014 13:11:45 +0000 (+0100)
Subject: efi: Pass correct file handle to efi_file_{read,close}
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e504a78c9336d920d48566dc8adcd25f0b5d99b8;p=karo-tx-linux.git

efi: Pass correct file handle to efi_file_{read,close}

commit 47514c996fac5e6f13ef3a4c5e23f1c5cffabb7b upstream.

We're currently passing the file handle for the root file system to
efi_file_read() and efi_file_close(), instead of the file handle for the
file we wish to read/close.

While this has worked up until now, it seems that it has only been by
pure luck. Olivier explains,

 "The issue is the UEFI Fat driver might return the same function for
  'fh->read()' and 'h->read()'. While in our case it does not work with
  a different implementation of EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. In our
  case, we return a different pointer when reading a directory and
  reading a file."

Fixing this actually clears up the two functions because we can drop one
of the arguments, and instead only pass a file 'handle' argument.

Reported-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c
index b6bffbfd3be7..3a74def216a5 100644
--- a/drivers/firmware/efi/efi-stub-helper.c
+++ b/drivers/firmware/efi/efi-stub-helper.c
@@ -468,7 +468,7 @@ grow:
 					chunksize = EFI_READ_CHUNK_SIZE;
 				else
 					chunksize = size;
-				status = efi_call_phys3(fh->read,
+				status = efi_call_phys3(files[j].handle->read,
 							files[j].handle,
 							&chunksize,
 							(void *)addr);
@@ -480,7 +480,7 @@ grow:
 				size -= chunksize;
 			}
 
-			efi_call_phys1(fh->close, files[j].handle);
+			efi_call_phys1(files[j].handle->close, files[j].handle);
 		}
 
 	}
@@ -497,7 +497,7 @@ free_file_total:
 
 close_handles:
 	for (k = j; k < i; k++)
-		efi_call_phys1(fh->close, files[k].handle);
+		efi_call_phys1(files[k].handle->close, files[k].handle);
 free_files:
 	efi_call_phys1(sys_table_arg->boottime->free_pool, files);
 fail: