[PATCH 1/3] arm64: kexec: Initialize kexec_buf struct in load_other_segments()

Breno Leitao posted 3 patches 1 month, 1 week ago
[PATCH 1/3] arm64: kexec: Initialize kexec_buf struct in load_other_segments()
Posted by Breno Leitao 1 month, 1 week ago
The kexec_buf structure was previously declared without initialization.
commit bf454ec31add ("kexec_file: allow to place kexec_buf randomly")
added a field that is always read but not consistently populated by all
architectures. This un-initialized field will contain garbage.

This is also triggering a UBSAN warning when the uninitialized data was
accessed:

	------------[ cut here ]------------
	UBSAN: invalid-load in ./include/linux/kexec.h:210:10
	load of value 252 is not a valid value for type '_Bool'

Zero-initializing kexec_buf at declaration ensures all fields are
cleanly set, preventing future instances of uninitialized memory being
used.

Signed-off-by: Breno Leitao <leitao@debian.org>
Fixes: bf454ec31add ("kexec_file: allow to place kexec_buf randomly")
---
 arch/arm64/kernel/machine_kexec_file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index af1ca875c52ce..410060ebd86df 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -94,7 +94,7 @@ int load_other_segments(struct kimage *image,
 			char *initrd, unsigned long initrd_len,
 			char *cmdline)
 {
-	struct kexec_buf kbuf;
+	struct kexec_buf kbuf = {};
 	void *dtb = NULL;
 	unsigned long initrd_load_addr = 0, dtb_len,
 		      orig_segments = image->nr_segments;

-- 
2.47.3