[PATCH AUTOSEL 4.19 314/671] s390/kexec_file: Fix potential segment overlap in ELF loader

Sasha Levin
2020-01-16T19:00:04Z

From: Philipp Rudo <prudo@linux.ibm.com>

[ Upstream commit 6339a3889ad4d0dd930ed7a1e873fb81d3e690f7 ]

When loading an ELF image via kexec_file the segment alignment is ignored
in the calculation for the load address of the next segment. When there are
multiple segments this can lead to segment overlap and thus load failure.

Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Fixes: 8be018827154 ("s390/kexec_file: Add ELF loader")
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/s390/kernel/kexec_elf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/kernel/kexec_elf.c b/arch/s390/kernel/kexec_elf.c
index 602e7cc26d11..5cf340b778f1 100644
--- a/arch/s390/kernel/kexec_elf.c
+++ b/arch/s390/kernel/kexec_elf.c
@@ -58,7 +58,7 @@ static int kexec_file_add_elf_kernel(struct kimage *image,
if (ret)
return ret;

- data->memsz += buf.memsz;
+ data->memsz = ALIGN(data->memsz, phdr->p_align) + buf.memsz;
}

return 0;
--
2.20.1