clang-analyzer says:
MokManager.c:1431:6: warning: Branch condition evaluates to a garbage value
if (mok)
^~~
MokManager.c:1433:6: warning: Branch condition evaluates to a garbage value
if (del_key)
^~~~~~~
And it's right; if we take the first error exit in the function, those
never get initialized. This patch sets them to NULL to begin with.
Signed-off-by: Peter Jones <pjones@redhat.com>
Covscan daftly claims:
288. var_compare_op: Comparing MokSB to null implies that MokSB might be null.
2330 if (MokSB) {
2331 menu_strings[i] = L"Change Secure Boot state";
2332 menu_item[i] = MOK_CHANGE_SB;
2333 i++;
2334 }
2335
...
2358 choice = console_select(perform_mok_mgmt, menu_strings, 0);
2359 if (choice < 0)
2360 goto out;
...
2362 switch (menu_item[choice]) {
...
2395 case MOK_CHANGE_SB:
CID 182841 (#1 of 1): Dereference after null check
(FORWARD_NULL)293. var_deref_model: Passing null pointer MokSB to
mok_sb_prompt, which dereferences it. [show details]
2396 efi_status = mok_sb_prompt(MokSB, MokSBSize);
Which is, of course, entirely false, beause for menu_item[choice] to be
MOK_CHANGE_SB, MokSB must be !NULL. And then:
252. Condition efi_status == 0, taking true branch.
2397 if (efi_status == EFI_SUCCESS)
2398 MokSB = NULL;
This guarantees it won't be in the list the next time through the loop.
This adds tests for NULLness before mok_sb_prompt(), just to make it
more clear to covscan what's going on.
Also do the same thing for all of:
MOK_CHANGE_SB
MOK_SET_PW
MOK_CHANGE_DB
MOK_ENROLL_MOKX
MOK_DELETE_MOKX
I also Lindent-ed everything I had to touch.
Three other minor errors are also fixed:
1) the loop in enter_mok_menu() leaked the menu allocations each time
through the loop
2) mok_sb_prompt(), mok_pw_prompt(), and mok_db_prompt() all call
FreePool() on their respective variables (MokSB, etc), and
check_mok_request() also calls FreePool() on these. This sounds
horrible, but it turns out it's not an issue, because they only free
them in their EFI_SUCCESS paths, and enter_mok_menu() resets the
system if any of the mok_XX_prompt() calls actually returned
EFI_SUCCESS, so we never get back to check_mok_request() for it to do
its FreePool() calls.
3) the loop in enter_mok_menu() winds up introducing a double free in
the call to free_menu(), but we also can't hit this bug, because all
the exit paths from the loop are "goto out" (or return error) rather
than actually exiting on the loop conditional.
Signed-off-by: Peter Jones <pjones@redhat.com>
Also consistently name our status variable "efi_status" unless there's a
good reason not to, such as already having another one of those.
Signed-off-by: Peter Jones <pjones@redhat.com>
We know it's legit already because we computed the pointer from the end,
but covscan gets confused, and we have StrnCat, so we should just use it
anyway.
Signed-off-by: Peter Jones <pjones@redhat.com>
Also consistently name our status variable "efi_status" unless there's a
good reason not to, such as already having another one of those.
Signed-off-by: Peter Jones <pjones@redhat.com>
clang-analyzer correctly believes this:
465 int i;
466
467 i = StrLen(name) - 1;
^ Value stored to 'i' is never read
468
469 for (i = StrLen(name); i > 0; --i) {
470 if (name[i] == '\\')
471 break;
472 }
And it's right; that's completely dead code.
Signed-off-by: Peter Jones <pjones@redhat.com>
Because they don't believe code should be defensive against future
changes, covscan believes:
520 out_free:
521 FreePool(dmp);
CID 182824 (#1 of 1): Dereference before null check
(REVERSE_INULL)check_after_deref: Null-checking entries suggests that
it may be null, but it has already been dereferenced on all paths
leading to the check.
522 if (entries) {
523 free_entries(entries, count);
524 FreePool(entries);
525 }
526 out_free_name:
527 FreePool(name);
528}
Which is technically correct, but still kind of dumb. So this patch
combines the two error out paths into just being out_free, so that the
first path there is before entries is allocated. (It also initializes
dmp to NULL and checks that before freeing it.)
I also Lindent-ed that function.
Signed-off-by: Peter Jones <pjones@redhat.com>
Obviously, these are not correct. Most of them are just useless; one
can be changed to a more useful test.
Signed-off-by: Peter Jones <pjones@redhat.com>
This commit fixes 2 issues with the TPM support code:
1) Remove "REQUIRE_TPM ?=" line from the Makefile, further down the Makefile
checks if REQUIRE_TPM is undefined, but the above line sets it to an empty
string, which is not the same as undefined. Without this handle_image fails
after the tpm_log_pe() call even if REQUIRE_TPM=1 once was not set when
building the shim
2) When secure-boot is disabled then shim_verify() would exit with the
status of tpm_log_pe(), which on systems with a TPM is an error. Combined
with the recent change to always install the shim protocols, this causes
grub to refuse to boot any kernel since the verify() call now always fails.
This commit fixes this by explicitly setting status = EFI_SUCCESS when
secure-boot is disabled.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Currently the shim_lock protocol is only installed when SecureBoot is enabled.
However, having Verify just measure into the TPM without SecureBoot is a useful
feature.
Signed-off-by: Tamas K Lengyel <lengyelt@ainfosec.com>
Currently the only measurement the shim logs in the TPM is that of the EFI
application it directly loads. However, there are no measurements being taken
of application that are being verified through the shim_lock protocol. In this
patch we extend PCR4 for any binary for which Verify is being called through
the shim_lock protocol.
Signed-off-by: Tamas K Lengyel <lengyelt@ainfosec.com>
Originally, we check if the last 2 nodes in the device path are
IPv4()/Uri() or IPv6()/Uri() to determine whether httpboot is used or
not. However, since UEFI 2.7, the DNS node will be inserted between the
IP node and the URI node if the server provides the DNS server address.
This commit changes the matching rule to search IP node and URI node
and ignore any node between those two nodes.
Signed-off-by: Gary Lin <glin@suse.com>
Make sure if we chainload things, a chainloaded bootloader will be able to use
the latest systab replacements and protocols. They need to match for things
to validate correctly.
Signed-off-by: Mathieu Trudel-Lapierre <mathieu.trudel-lapierre@canonical.com>
shim 13:
- OpenSSL reverted to 1.0.2k to make the cert chaining of existing deployments stay working
- Better PCR usage for TPM
- TPM documentation in README.tpm
- More configurable build via make variables:
ENABLE_SHIM_CERT
ENABLE_SHIM_HASH
ENABLE_SBSIGN
LIBDIR
EFIDIR
VENDOR_CERT_FILE
VENDOR_DB_FILE
- Better MoK documentation in MokVars.txt
- Better debuginfo generation
- Lots of minor bug fixes.
Signed-off-by: Peter Jones <pjones@redhat.com>
If you build with ENABLE_SHIM_CERT=1, the include chain right now winds
up meaning shim_cert is defined in a header that gets included in
netboot.c as well, which never uses it:
In file included from shim.h:125:0,
from netboot.c:36:
shim_cert.h:1:14: error: ‘shim_cert’ defined but not used [-Werror=unused-variable]
static UINT8 shim_cert[] = {
^~~~~~~~~
cc1: all warnings being treated as errors
So make that okay by adding __attribute__((__unused__)) to the variable
decl.
Signed-off-by: Peter Jones <pjones@redhat.com>
