[PATCH 1/1] kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y

[Petr Tesarik]

From: Petr Tesarik <ptesarik@xxxxxxxx>

Fix the condition to exclude the elfcorehdr segment from the SHA digest
calculation.

The j iterator is an index into the output sha_regions[] array, not into
the input image->segment[] array. Once it reaches image->elfcorehdr_index,
all subsequent segments are excluded. Besides, if the purgatory segment
precedes the elfcorehdr segment, the elfcorehdr may be wrongly included in
the calculation.

Fixes: f7cc804a9fd4 ("kexec: exclude elfcorehdr from the segment digest")
Cc: stable@xxxxxxxxxx
Signed-off-by: Petr Tesarik <ptesarik@xxxxxxxx>
---
 kernel/kexec_file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 3d64290d24c9..3eedb8c226ad 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -752,7 +752,7 @@ static int kexec_calculate_store_digests(struct kimage *image)
 
 #ifdef CONFIG_CRASH_HOTPLUG
 		/* Exclude elfcorehdr segment to allow future changes via hotplug */
-		if (j == image->elfcorehdr_index)
+		if (i == image->elfcorehdr_index)
 			continue;
 #endif
 
-- 
2.45.2