From bc3f46518176e541c767b099fb06ad1870d59fa5 Mon Sep 17 00:00:00 2001
From: Peng Fan <peng.fan@nxp.com>
Date: Wed, 28 Apr 2021 21:54:01 +0800
Subject: [PATCH] efi_loader: loosen buffer parameter check in
efi_file_read_int
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This is same issue as https://bugzilla.redhat.com/show_bug.cgi?id=1733817,
but that fix was wrongly partial reverted.
When reading a directory, EFI_BUFFER_TOO_SMALL should be returned when
the supplied buffer is too small, so a use-case is to call
EFI_FILE_PROTOCOL.Read() with *buffer_size=0 and buffer=NULL to
obtain the needed size before doing the actual read.
So remove the check only for directory reading, file reading already
do the check by itself.
Fixes: db12f518edb0("efi_loader: implement non-blocking file services")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefan Sørensen <stefan.sorensen@spectralink.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---
lib/efi_loader/efi_file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 204105e25a..6b3f5962be 100644
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -554,7 +554,7 @@ static efi_status_t efi_file_read_int(struct efi_file_handle *this,
efi_status_t ret = EFI_SUCCESS;
u64 bs;
- if (!this || !buffer_size || !buffer)
+ if (!this || !buffer_size)
return EFI_INVALID_PARAMETER;
bs = *buffer_size;
--
2.39.5