File kexec-tools-Add-option-to-fall-back-to-KEXEC_LOAD.patch of Package kexec-tools
From: Michal Suchanek <msuchanek@suse.de>
Date: Mon, 26 Feb 2018 12:24:44 +0100
Subject: kexec: Add option to fall back to KEXEC_LOAD when KEXEC_FILE_LOAD
is not supported
References: bsc#1080916, boo#1076839
Upstream: merged
Git-commit: 9fa99c42cb911727a962b358c5b1d36d0fe338ab
Not all architectures implement KEXEC_FILE_LOAD. However, on some
archiectures KEXEC_FILE_LOAD is required when secure boot is enabled in
locked-down mode. Previously users had to select the KEXEC_FILE_LOAD
syscall with undocumented -s option. However, if they did pass the
option kexec would fail on architectures that do not support it.
So add an -a option that tries KEXEC_FILE_LOAD and when it is not
supported tries KEXEC_LOAD.
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
v3: instead of changing the deafult add extra option
v4: actually check -ENOSYS as well
v5: add missing break
v6:
- add note about ENOTSUPP
- add description to help text
---
kexec/kexec.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
kexec/kexec.h | 4 +++-
2 files changed, 63 insertions(+), 6 deletions(-)
diff --git a/kexec/kexec.c b/kexec/kexec.c
index 87689311af2f..612c1c2afbe5 100644
--- a/kexec/kexec.c
+++ b/kexec/kexec.c
@@ -1007,6 +1007,10 @@ void usage(void)
" -s, --kexec-file-syscall Use file based syscall for kexec operation\n"
" -c, --kexec-syscall Use the kexec_load syscall for for compatibility\n"
" with systems that don't support -s (default)\n"
+ " -a, --kexec-syscall-auto Use file based syscall for kexec and fall\n"
+ " back to the compatibility syscall when file based\n"
+ " syscall is not supported or the kernel did not\n"
+ " understand the image\n"
" -d, --debug Enable debugging to help spot a failure.\n"
" -S, --status Return 0 if the type (by default crash) is loaded.\n"
"\n"
@@ -1245,6 +1249,7 @@ int main(int argc, char *argv[])
int do_unload = 0;
int do_reuse_initrd = 0;
int do_kexec_file_syscall = 0;
+ int do_kexec_fallback = 0;
int do_status = 0;
void *entry = 0;
char *type = 0;
@@ -1369,9 +1374,15 @@ int main(int argc, char *argv[])
break;
case OPT_KEXEC_FILE_SYSCALL:
do_kexec_file_syscall = 1;
+ do_kexec_fallback = 0;
break;
case OPT_KEXEC_SYSCALL:
do_kexec_file_syscall = 0;
+ do_kexec_fallback = 0;
+ break;
+ case OPT_KEXEC_SYSCALL_AUTO:
+ do_kexec_file_syscall = 1;
+ do_kexec_fallback = 1;
break;
case OPT_STATUS:
do_status = 1;
@@ -1438,7 +1449,7 @@ int main(int argc, char *argv[])
}
}
if (do_kexec_file_syscall) {
- if (do_load_jump_back_helper)
+ if (do_load_jump_back_helper && !do_kexec_fallback)
die("--load-jump-back-helper not supported with kexec_file_load\n");
if (kexec_flags & KEXEC_PRESERVE_CONTEXT)
die("--load-preserve-context not supported with kexec_file_load\n");
@@ -1452,16 +1463,60 @@ int main(int argc, char *argv[])
result = k_status(kexec_flags);
}
if (do_unload) {
- if (do_kexec_file_syscall)
+ if (do_kexec_file_syscall) {
result = kexec_file_unload(kexec_file_flags);
- else
+ if ((result == -ENOSYS) && do_kexec_fallback)
+ do_kexec_file_syscall = 0;
+ }
+ if (!do_kexec_file_syscall)
result = k_unload(kexec_flags);
}
if (do_load && (result == 0)) {
- if (do_kexec_file_syscall)
+ if (do_kexec_file_syscall) {
result = do_kexec_file_load(fileind, argc, argv,
kexec_file_flags);
- else
+ if (do_kexec_fallback) switch (result) {
+ /*
+ * Something failed with signature verification.
+ * Reject the image.
+ */
+ case -ELIBBAD:
+ case -EKEYREJECTED:
+ case -ENOPKG:
+ case -ENOKEY:
+ case -EBADMSG:
+ case -EMSGSIZE:
+ /*
+ * By default reject or do nothing if
+ * succeded
+ */
+ default: break;
+ case -ENOSYS: /* not implemented */
+ /*
+ * Parsing image or other options failed
+ * The image may be invalid or image
+ * type may not supported by kernel so
+ * retry parsing in kexec-tools.
+ */
+ case -EINVAL:
+ case -ENOEXEC:
+ /*
+ * ENOTSUP can be unsupported image
+ * type or unsupported PE signature
+ * wrapper type, duh
+ *
+ * The kernel sometimes wrongly
+ * returns ENOTSUPP (524) - ignore
+ * that. It is not supposed to be seen
+ * by userspace so seeing it is a
+ * kernel bug
+ */
+ case -ENOTSUP:
+ do_kexec_file_syscall = 0;
+ break;
+ }
+ }
+ if (!do_kexec_file_syscall)
result = my_load(type, fileind, argc, argv,
kexec_flags, entry);
}
diff --git a/kexec/kexec.h b/kexec/kexec.h
index 9fd0355eacd0..d445fbe3e486 100644
--- a/kexec/kexec.h
+++ b/kexec/kexec.h
@@ -220,6 +220,7 @@ extern int file_types;
#define OPT_PANIC 'p'
#define OPT_KEXEC_FILE_SYSCALL 's'
#define OPT_KEXEC_SYSCALL 'c'
+#define OPT_KEXEC_SYSCALL_AUTO 'a'
#define OPT_STATUS 'S'
#define OPT_MEM_MIN 256
#define OPT_MEM_MAX 257
@@ -248,11 +249,12 @@ extern int file_types;
{ "reuseinitrd", 0, 0, OPT_REUSE_INITRD }, \
{ "kexec-file-syscall", 0, 0, OPT_KEXEC_FILE_SYSCALL }, \
{ "kexec-syscall", 0, 0, OPT_KEXEC_SYSCALL }, \
+ { "kexec-syscall-auto", 0, 0, OPT_KEXEC_SYSCALL_AUTO }, \
{ "debug", 0, 0, OPT_DEBUG }, \
{ "status", 0, 0, OPT_STATUS }, \
{ "print-ckr-size", 0, 0, OPT_PRINT_CKR_SIZE }, \
-#define KEXEC_OPT_STR "h?vdfxyluet:pscS"
+#define KEXEC_OPT_STR "h?vdfxyluet:pscaS"
extern void dbgprint_mem_range(const char *prefix, struct memory_range *mr, int nr_mr);
extern void die(const char *fmt, ...)
--
2.13.6