[tip: x86/urgent] x86/kexec: Fix double-free of elf header buffer

[tip-bot2 for Takashi Iwai]

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     d00dd2f2645dca04cf399d8fc692f3f69b6dd996
Gitweb:        https://git.kernel.org/tip/d00dd2f2645dca04cf399d8fc692f3f69b6dd996
Author:        Takashi Iwai <tiwai@xxxxxxx>
AuthorDate:    Tue, 22 Nov 2022 12:51:22 +01:00
Committer:     Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Mon, 02 Jan 2023 18:56:21 +01:00

x86/kexec: Fix double-free of elf header buffer

After

  b3e34a47f989 ("x86/kexec: fix memory leak of elf header buffer"),

freeing image->elf_headers in the error path of crash_load_segments()
is not needed because kimage_file_post_load_cleanup() will take
care of that later. And not clearing it could result in a double-free.

Drop the superfluous vfree() call at the error path of
crash_load_segments().

Fixes: b3e34a47f989 ("x86/kexec: fix memory leak of elf header buffer")
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Acked-by: Baoquan He <bhe@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221122115122.13937-1-tiwai@xxxxxxx
---
 arch/x86/kernel/crash.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 9730c88..3055144 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -401,10 +401,8 @@ int crash_load_segments(struct kimage *image)
 	kbuf.buf_align = ELF_CORE_HEADER_ALIGN;
 	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
 	ret = kexec_add_buffer(&kbuf);
-	if (ret) {
-		vfree((void *)image->elf_headers);
+	if (ret)
 		return ret;
-	}
 	image->elf_load_addr = kbuf.mem;
 	pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
 		 image->elf_load_addr, kbuf.bufsz, kbuf.memsz);