Currently on the error exit path the allocated buffer is not free'd
causing a memory leak. Fix this by kfree'ing it.
Detected by CoverityScan, CID#1466876 ("Resource leaks")
Fixes: 1180b4c757 ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
When policy replacement occurs the symlinks in the profile directory
need to be updated to point to the new rawdata, otherwise once the
old rawdata is removed the symlink becomes broken.
Fix this by dynamically generating the symlink everytime it is read.
These links are used enough that their value needs to be cached and
this way we can avoid needing locking to read and update the link
value.
Fixes: a481f4d917 ("apparmor: add custom apparmorfs that will be used by policy namespace files")
BugLink: http://bugs.launchpad.net/bugs/1755563
Signed-off-by: John Johansen <john.johansen@canonical.com>
We accidentally return a positive EPROTO instead of a negative -EPROTO.
Since 71 is not an error pointer, that means it eventually results in an
Oops in the caller.
Fixes: d901d6a298 ("apparmor: dfa split verification of table headers")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Currently variable size is a unsigned size_t, hence comparisons to
see if it is less than zero (for error checking) will always be
false. Fix this by making size a ssize_t
Detected by CoverityScan, CID#1466080 ("Unsigned compared against 0")
Fixes: 8e51f9087f ("apparmor: Add support for attaching profiles via xattr, presence and value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The unpack code now makes sure every profile has a dfa so the safe
version of POLICY_MEDIATES is no longer needed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
version 2 - Force an abi break. Network mediation will only be
available in v8 abi complaint policy.
Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.
the user space rule hav the basic form of
NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
[ TYPE | PROTOCOL ]
DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
'vsock' | 'mpls' | 'ib' | 'kcm' ) ','
TYPE = ( 'stream' | 'dgram' | 'seqpacket' | 'rdm' | 'raw' |
'packet' )
PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )
eg.
network,
network inet,
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Overlapping domain attachments using the current longest left exact
match fail in some simple cases, and with the fix to ensure consistent
behavior by failing unresolvable attachments it becomes important to
do a better job.
eg. under the current match the following are unresolvable where
the alternation is clearly a better match under the most specific
left match rule.
/**
/{bin/,}usr/
Use a counting match that detects when a loop in the state machine is
enter, and return the match count to provide a better specific left
match resolution.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This converts profile attachment based on xattrs to a fixed extended
conditional using dfa matching.
This has a couple of advantages
- pattern matching can be used for the xattr match
- xattrs can be optional for an attachment or marked as required
- the xattr attachment conditional will be able to be combined with
other extended conditionals when the flexible extended conditional
work lands.
The xattr fixed extended conditional is appended to the xmatch
conditional. If an xattr attachment is specified the profile xmatch
will be generated regardless of whether there is a pattern match on
the executable name.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Make it possible to tie Apparmor profiles to the presence of one or more
extended attributes, and optionally their values. An example usecase for
this is to automatically transition to a more privileged Apparmor profile
if an executable has a valid IMA signature, which can then be appraised
by the IMA subsystem.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
separate the different types of verification so they are logically
separate and can be reused separate of each other.
Signed-off-by: John Johansen <john.johansen@canonical.com>
State differential encoding can provide better compression for
apparmor policy, without having significant impact on match time.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Domain transition so far have been largely blocked by no new privs,
unless the transition has been provably a subset of the previous
confinement. There was a couple problems with the previous
implementations,
- transitions that weren't explicitly a stack but resulted in a subset
of confinement were disallowed
- confinement subsets were only calculated from the previous
confinement instead of the confinement being enforced at the time of
no new privs, so transitions would have to get progressively
tighter.
Fix this by detecting and storing a reference to the task's
confinement at the "time" no new privs is set. This reference is then
used to determine whether a transition is a subsystem of the
confinement at the time no new privs was set.
Unfortunately the implementation is less than ideal in that we have to
detect no new privs after the fact when a task attempts a domain
transition. This is adequate for the currently but will not work in a
stacking situation where no new privs could be conceivably be set in
both the "host" and in the container.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Now that file contexts have been moved into file, and task context
fns() and data have been split from the context, only the cred context
remains in context.h so rename to cred.h to better reflect what it
deals with.
Signed-off-by: John Johansen <john.johansen@canonical.com>
now that cred_ctx has been removed we can rename task_ctxs from tctx
without causing confusion.
Signed-off-by: John Johansen <john.johansen@canonical.com>
With the task domain change information now stored in the task->security
context, the cred->security context only stores the label. We can get
rid of the cred_ctx and directly reference the label, removing a layer
of indirection, and unneeded extra allocations.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The task domain change info is task specific and its and abuse of
the cred to store the information in there. Now that a task->security
field exists store it in the proper place.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Allow apparmor to audit the number of a signal that it does not
provide a mapping for and is currently being reported only as
unknown.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Given a label with a profile stack of
A//&B or A//&C ...
A ptrace rule should be able to specify a generic trace pattern with
a rule like
signal send A//&**,
however this is failing because while the correct label match routine
is called, it is being done post label decomposition so it is always
being done against a profile instead of the stacked label.
To fix this refactor the cross check to pass the full peer label in to
the label_match.
Signed-off-by: John Johansen <john.johansen@canonical.com>
These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.
Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The root view of the label parse should not be exposed to user
control.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
nulldfa.in makes for a very long unwrapped line, which certain tools
do not like. So add line breaks.
Signed-off-by: John Johansen <john.johansen@canonical.com>
some label/context sources might not be guaranteed to be null terminiated
provide a size bounded version of label parse to deal with these.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
The current split scheme is actually wrong in that it splits
///&
where that is invalid and should fail. Use the dfa to do a proper
bounded split without having to worry about getting the string
processing right in code.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Splitting the management struct from the actual data blob will allow
us in the future to do some sharing and other data reduction
techniques like replacing the the raw data with compressed data.
Prepare for this by separating the management struct from the data
blob.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The existence test is not being properly logged as the signal mapping
maps it to the last entry in the named signal table. This is done
to help catch bugs by making the 0 mapped signal value invalid so
that we can catch the signal value not being filled in.
When fixing the off-by-one comparision logic the reporting of the
existence test was broken, because the logic behind the mapped named
table was hidden. Fix this by adding a define for the name lookup
and using it.
Cc: Stable <stable@vger.kernel.org>
Fixes: f7dc4c9a85 ("apparmor: fix off-by-one comparison on MAXMAPPED_SIG")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Resource auditing is using the peer field which is not available
when the rlim data struct is used, because it is a different element
of the same union. Accessing peer during resource auditing could
cause garbage log entries or even oops the kernel.
Move the rlim data block into the same struct as the peer field
so they can be used together.
CC: <stable@vger.kernel.org>
Fixes: 86b92cb782 ("apparmor: move resource checks to using labels")
Signed-off-by: John Johansen <john.johansen@canonical.com>
The .ns_name should not be virtualized by the current ns view. It
needs to report the ns base name as that is being used during startup
as part of determining apparmor policy namespace support.
BugLink: http://bugs.launchpad.net/bugs/1746463
Fixes: d9f02d9c23 ("apparmor: fix display of ns name")
Cc: Stable <stable@vger.kernel.org>
Reported-by: Serge Hallyn <serge@hallyn.com>
Tested-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Pull x86 pti updates from Thomas Gleixner:
"This contains:
- a PTI bugfix to avoid setting reserved CR3 bits when PCID is
disabled. This seems to cause issues on a virtual machine at least
and is incorrect according to the AMD manual.
- a PTI bugfix which disables the perf BTS facility if PTI is
enabled. The BTS AUX buffer is not globally visible and causes the
CPU to fault when the mapping disappears on switching CR3 to user
space. A full fix which restores BTS on PTI is non trivial and will
be worked on.
- PTI bugfixes for EFI and trusted boot which make sure that the user
space visible page table entries have the NX bit cleared
- removal of dead code in the PTI pagetable setup functions
- add PTI documentation
- add a selftest for vsyscall to verify that the kernel actually
implements what it advertises.
- a sysfs interface to expose vulnerability and mitigation
information so there is a coherent way for users to retrieve the
status.
- the initial spectre_v2 mitigations, aka retpoline:
+ The necessary ASM thunk and compiler support
+ The ASM variants of retpoline and the conversion of affected ASM
code
+ Make LFENCE serializing on AMD so it can be used as speculation
trap
+ The RSB fill after vmexit
- initial objtool support for retpoline
As I said in the status mail this is the most of the set of patches
which should go into 4.15 except two straight forward patches still on
hold:
- the retpoline add on of LFENCE which waits for ACKs
- the RSB fill after context switch
Both should be ready to go early next week and with that we'll have
covered the major holes of spectre_v2 and go back to normality"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
x86,perf: Disable intel_bts when PTI
security/Kconfig: Correct the Documentation reference for PTI
x86/pti: Fix !PCID and sanitize defines
selftests/x86: Add test_vsyscall
x86/retpoline: Fill return stack buffer on vmexit
x86/retpoline/irq32: Convert assembler indirect jumps
x86/retpoline/checksum32: Convert assembler indirect jumps
x86/retpoline/xen: Convert Xen hypercall indirect jumps
x86/retpoline/hyperv: Convert assembler indirect jumps
x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
x86/retpoline/entry: Convert entry assembler indirect jumps
x86/retpoline/crypto: Convert crypto assembler indirect jumps
x86/spectre: Add boot time option to select Spectre v2 mitigation
x86/retpoline: Add initial retpoline support
objtool: Allow alternatives to be ignored
objtool: Detect jumps to retpoline thunks
x86/pti: Make unpoison of pgd for trusted boot work for real
x86/alternatives: Fix optimize_nops() checking
sysfs/cpu: Fix typos in vulnerability documentation
x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
...
The intended behaviour in apparmor profile matching is to flag a
conflict if two profiles match equally well. However, right now a
conflict is generated if another profile has the same match length even
if that profile doesn't actually match. Fix the logic so we only
generate a conflict if the profiles match.
Fixes: 844b8292b6 ("apparmor: ensure that undecidable profile attachments fail")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Given a label with a profile stack of
A//&B or A//&C ...
A ptrace rule should be able to specify a generic trace pattern with
a rule like
ptrace trace A//&**,
however this is failing because while the correct label match routine
is called, it is being done post label decomposition so it is always
being done against a profile instead of the stacked label.
To fix this refactor the cross check to pass the full peer label in to
the label_match.
Fixes: 290f458a4f ("apparmor: allow ptrace checks to be finer grained than just capability")
Cc: Stable <stable@vger.kernel.org>
Reported-by: Matthew Garrett <mjg59@google.com>
Tested-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
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Merge tag 'apparmor-pr-2018-01-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor fix from John Johansen:
"This fixes a regression when the kernel feature set is reported as
supporting mount and policy is pinned to a feature set that does not
support mount mediation"
* tag 'apparmor-pr-2018-01-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: fix regression in mount mediation when feature set is pinned
When the mount code was refactored for Labels it was not correctly
updated to check whether policy supported mediation of the mount
class. This causes a regression when the kernel feature set is
reported as supporting mount and policy is pinned to a feature set
that does not support mount mediation.
BugLink: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=882697#41
Fixes: 2ea3ffb778 ("apparmor: add mount mediation")
Reported-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Pull x86 page table isolation fixes from Thomas Gleixner:
"A couple of urgent fixes for PTI:
- Fix a PTE mismatch between user and kernel visible mapping of the
cpu entry area (differs vs. the GLB bit) and causes a TLB mismatch
MCE on older AMD K8 machines
- Fix the misplaced CR3 switch in the SYSCALL compat entry code which
causes access to unmapped kernel memory resulting in double faults.
- Fix the section mismatch of the cpu_tss_rw percpu storage caused by
using a different mechanism for declaration and definition.
- Two fixes for dumpstack which help to decode entry stack issues
better
- Enable PTI by default in Kconfig. We should have done that earlier,
but it slipped through the cracks.
- Exclude AMD from the PTI enforcement. Not necessarily a fix, but if
AMD is so confident that they are not affected, then we should not
burden users with the overhead"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/process: Define cpu_tss_rw in same section as declaration
x86/pti: Switch to kernel CR3 at early in entry_SYSCALL_compat()
x86/dumpstack: Print registers for first stack frame
x86/dumpstack: Fix partial register dumps
x86/pti: Make sure the user/kernel PTEs match
x86/cpu, x86/pti: Do not enable PTI on AMD processors
x86/pti: Enable PTI by default
This really want's to be enabled by default. Users who know what they are
doing can disable it either in the config or on the kernel command line.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
If userspace attempted to set a "security.capability" xattr shorter than
4 bytes (e.g. 'setfattr -n security.capability -v x file'), then
cap_convert_nscap() read past the end of the buffer containing the xattr
value because it accessed the ->magic_etc field without verifying that
the xattr value is long enough to contain that field.
Fix it by validating the xattr value size first.
This bug was found using syzkaller with KASAN. The KASAN report was as
follows (cleaned up slightly):
BUG: KASAN: slab-out-of-bounds in cap_convert_nscap+0x514/0x630 security/commoncap.c:498
Read of size 4 at addr ffff88002d8741c0 by task syz-executor1/2852
CPU: 0 PID: 2852 Comm: syz-executor1 Not tainted 4.15.0-rc6-00200-gcc0aac99d977 #253
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xe3/0x195 lib/dump_stack.c:53
print_address_description+0x73/0x260 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report+0x235/0x350 mm/kasan/report.c:409
cap_convert_nscap+0x514/0x630 security/commoncap.c:498
setxattr+0x2bd/0x350 fs/xattr.c:446
path_setxattr+0x168/0x1b0 fs/xattr.c:472
SYSC_setxattr fs/xattr.c:487 [inline]
SyS_setxattr+0x36/0x50 fs/xattr.c:483
entry_SYSCALL_64_fastpath+0x18/0x85
Fixes: 8db6c34f1d ("Introduce v3 namespaced file capabilities")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Pull x86 page table isolation updates from Thomas Gleixner:
"This is the final set of enabling page table isolation on x86:
- Infrastructure patches for handling the extra page tables.
- Patches which map the various bits and pieces which are required to
get in and out of user space into the user space visible page
tables.
- The required changes to have CR3 switching in the entry/exit code.
- Optimizations for the CR3 switching along with documentation how
the ASID/PCID mechanism works.
- Updates to dump pagetables to cover the user space page tables for
W+X scans and extra debugfs files to analyze both the kernel and
the user space visible page tables
The whole functionality is compile time controlled via a config switch
and can be turned on/off on the command line as well"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
x86/ldt: Make the LDT mapping RO
x86/mm/dump_pagetables: Allow dumping current pagetables
x86/mm/dump_pagetables: Check user space page table for WX pages
x86/mm/dump_pagetables: Add page table directory to the debugfs VFS hierarchy
x86/mm/pti: Add Kconfig
x86/dumpstack: Indicate in Oops whether PTI is configured and enabled
x86/mm: Clarify the whole ASID/kernel PCID/user PCID naming
x86/mm: Use INVPCID for __native_flush_tlb_single()
x86/mm: Optimize RESTORE_CR3
x86/mm: Use/Fix PCID to optimize user/kernel switches
x86/mm: Abstract switching CR3
x86/mm: Allow flushing for future ASID switches
x86/pti: Map the vsyscall page if needed
x86/pti: Put the LDT in its own PGD if PTI is on
x86/mm/64: Make a full PGD-entry size hole in the memory map
x86/events/intel/ds: Map debug buffers in cpu_entry_area
x86/cpu_entry_area: Add debugstore entries to cpu_entry_area
x86/mm/pti: Map ESPFIX into user space
x86/mm/pti: Share entry text PMD
x86/entry: Align entry text section to PMD boundary
...
Finally allow CONFIG_PAGE_TABLE_ISOLATION to be enabled.
PARAVIRT generally requires that the kernel not manage its own page tables.
It also means that the hypervisor and kernel must agree wholeheartedly
about what format the page tables are in and what they contain.
PAGE_TABLE_ISOLATION, unfortunately, changes the rules and they
can not be used together.
I've seen conflicting feedback from maintainers lately about whether they
want the Kconfig magic to go first or last in a patch series. It's going
last here because the partially-applied series leads to kernels that can
not boot in a bunch of cases. I did a run through the entire series with
CONFIG_PAGE_TABLE_ISOLATION=y to look for build errors, though.
[ tglx: Removed SMP and !PARAVIRT dependencies as they not longer exist ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
keyctl_restrict_keyring() allows through a NULL restriction when the
"type" is non-NULL, which causes a NULL pointer dereference in
asymmetric_lookup_restriction() when it calls strcmp() on the
restriction string.
But no key types actually use a "NULL restriction" to mean anything, so
update keyctl_restrict_keyring() to reject it with EINVAL.
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 97d3aa0f31 ("KEYS: Add a lookup_restriction function for the asymmetric key type")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Variable key_ref is being assigned a value that is never read;
key_ref is being re-assigned a few statements later. Hence this
assignment is redundant and can be removed.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
When the request_key() syscall is not passed a destination keyring, it
links the requested key (if constructed) into the "default" request-key
keyring. This should require Write permission to the keyring. However,
there is actually no permission check.
This can be abused to add keys to any keyring to which only Search
permission is granted. This is because Search permission allows joining
the keyring. keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_SESSION_KEYRING)
then will set the default request-key keyring to the session keyring.
Then, request_key() can be used to add keys to the keyring.
Both negatively and positively instantiated keys can be added using this
method. Adding negative keys is trivial. Adding a positive key is a
bit trickier. It requires that either /sbin/request-key positively
instantiates the key, or that another thread adds the key to the process
keyring at just the right time, such that request_key() misses it
initially but then finds it in construct_alloc_key().
Fix this bug by checking for Write permission to the keyring in
construct_get_dest_keyring() when the default keyring is being used.
We don't do the permission check for non-default keyrings because that
was already done by the earlier call to lookup_user_key(). Also,
request_key_and_link() is currently passed a 'struct key *' rather than
a key_ref_t, so the "possessed" bit is unavailable.
We also don't do the permission check for the "requestor keyring", to
continue to support the use case described by commit 8bbf4976b5
("KEYS: Alter use of key instantiation link-to-keyring argument") where
/sbin/request-key recursively calls request_key() to add keys to the
original requestor's destination keyring. (I don't know of any users
who actually do that, though...)
Fixes: 3e30148c3d ("[PATCH] Keys: Make request-key create an authorisation key")
Cc: <stable@vger.kernel.org> # v2.6.13+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
In request_key_and_link(), in the case where the dest_keyring was
explicitly specified, there is no need to get another reference to
dest_keyring before calling key_link(), then drop it afterwards. This
is because by definition, we already have a reference to dest_keyring.
This change is useful because we'll be making
construct_get_dest_keyring() able to return an error code, and we don't
want to have to handle that error here for no reason.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
