diff options
| author | Philipp Rudo <prudo@linux.vnet.ibm.com> | 2018-04-14 01:36:39 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-14 03:10:28 +0300 |
| commit | 8da0b724959ccd3f8435214ebdaf1aef548967bb (patch) | |
| tree | 5614e73eb78981992032e7523bed4691b31c5a5a /arch | |
| parent | 620f697cc27a6d9b09268f47cd13620488ec67af (diff) | |
| download | linux-8da0b724959ccd3f8435214ebdaf1aef548967bb.tar.xz | |
kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory load
The current code uses the sh_offset field in purgatory_info->sechdrs to
store a pointer to the current load address of the section. Depending
whether the section will be loaded or not this is either a pointer into
purgatory_info->purgatory_buf or kexec_purgatory. This is not only a
violation of the ELF standard but also makes the code very hard to
understand as you cannot tell if the memory you are using is read-only
or not.
Remove this misuse and store the offset of the section in
pugaroty_info->purgatory_buf in sh_offset.
Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/machine_kexec_64.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 63dea30c8e02..a5e55d832d0a 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -417,13 +417,15 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi, * rel[i].r_offset contains byte offset from beginning * of section to the storage unit affected. * - * This is location to update (->sh_offset). This is temporary - * buffer where section is currently loaded. This will finally - * be loaded to a different address later, pointed to by + * This is location to update. This is temporary buffer + * where section is currently loaded. This will finally be + * loaded to a different address later, pointed to by * ->sh_addr. kexec takes care of moving it * (kexec_load_segment()). */ - location = (void *)(section->sh_offset + rel[i].r_offset); + location = pi->purgatory_buf; + location += section->sh_offset; + location += rel[i].r_offset; /* Final address of the location */ address = section->sh_addr + rel[i].r_offset; |