| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
dlm: fix possible lkb_resource null dereference
This patch fixes a possible null pointer dereference when this function is
called from request_lock() as lkb->lkb_resource is not assigned yet,
only after validate_lock_args() by calling attach_lkb(). Another issue
is that a resource name could be a non printable bytearray and we cannot
assume to be ASCII coded.
The log functionality is probably never being hit when DLM is used in
normal way and no debug logging is enabled. The null pointer dereference
can only occur on a new created lkb that does not have the resource
assigned yet, it probably never hits the null pointer dereference but we
should be sure that other changes might not change this behaviour and we
actually can hit the mentioned null pointer dereference.
In this patch we just drop the printout of the resource name, the lkb id
is enough to make a possible connection to a resource name if this
exists. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: call the security_mmap_file() LSM hook in remap_file_pages()
The remap_file_pages syscall handler calls do_mmap() directly, which
doesn't contain the LSM security check. And if the process has called
personality(READ_IMPLIES_EXEC) before and remap_file_pages() is called for
RW pages, this will actually result in remapping the pages to RWX,
bypassing a W^X policy enforced by SELinux.
So we should check prot by security_mmap_file LSM hook in the
remap_file_pages syscall handler before do_mmap() is called. Otherwise, it
potentially permits an attacker to bypass a W^X policy enforced by
SELinux.
The bypass is similar to CVE-2016-10044, which bypass the same thing via
AIO and can be found in [1].
The PoC:
$ cat > test.c
int main(void) {
size_t pagesz = sysconf(_SC_PAGE_SIZE);
int mfd = syscall(SYS_memfd_create, "test", 0);
const char *buf = mmap(NULL, 4 * pagesz, PROT_READ | PROT_WRITE,
MAP_SHARED, mfd, 0);
unsigned int old = syscall(SYS_personality, 0xffffffff);
syscall(SYS_personality, READ_IMPLIES_EXEC | old);
syscall(SYS_remap_file_pages, buf, pagesz, 0, 2, 0);
syscall(SYS_personality, old);
// show the RWX page exists even if W^X policy is enforced
int fd = open("/proc/self/maps", O_RDONLY);
unsigned char buf2[1024];
while (1) {
int ret = read(fd, buf2, 1024);
if (ret <= 0) break;
write(1, buf2, ret);
}
close(fd);
}
$ gcc test.c -o test
$ ./test | grep rwx
7f1836c34000-7f1836c35000 rwxs 00002000 00:01 2050 /memfd:test (deleted)
[PM: subject line tweaks] |
| In the Linux kernel, the following vulnerability has been resolved:
mm: avoid leaving partial pfn mappings around in error case
As Jann points out, PFN mappings are special, because unlike normal
memory mappings, there is no lifetime information associated with the
mapping - it is just a raw mapping of PFNs with no reference counting of
a 'struct page'.
That's all very much intentional, but it does mean that it's easy to
mess up the cleanup in case of errors. Yes, a failed mmap() will always
eventually clean up any partial mappings, but without any explicit
lifetime in the page table mapping itself, it's very easy to do the
error handling in the wrong order.
In particular, it's easy to mistakenly free the physical backing store
before the page tables are actually cleaned up and (temporarily) have
stale dangling PTE entries.
To make this situation less error-prone, just make sure that any partial
pfn mapping is torn down early, before any other error handling. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mvm: pause TCM when the firmware is stopped
Not doing so will make us send a host command to the transport while the
firmware is not alive, which will trigger a WARNING.
bad state = 0
WARNING: CPU: 2 PID: 17434 at drivers/net/wireless/intel/iwlwifi/iwl-trans.c:115 iwl_trans_send_cmd+0x1cb/0x1e0 [iwlwifi]
RIP: 0010:iwl_trans_send_cmd+0x1cb/0x1e0 [iwlwifi]
Call Trace:
<TASK>
iwl_mvm_send_cmd+0x40/0xc0 [iwlmvm]
iwl_mvm_config_scan+0x198/0x260 [iwlmvm]
iwl_mvm_recalc_tcm+0x730/0x11d0 [iwlmvm]
iwl_mvm_tcm_work+0x1d/0x30 [iwlmvm]
process_one_work+0x29e/0x640
worker_thread+0x2df/0x690
? rescuer_thread+0x540/0x540
kthread+0x192/0x1e0
? set_kthread_struct+0x90/0x90
ret_from_fork+0x22/0x30 |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: add bounds checking to ocfs2_xattr_find_entry()
Add a paranoia check to make sure it doesn't stray beyond valid memory
region containing ocfs2 xattr entries when scanning for a match. It will
prevent out-of-bound access in case of crafted images. |
| In the Linux kernel, the following vulnerability has been resolved:
lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc()
If we need to increase the tree depth, allocate a new node, and then
race with another thread that increased the tree depth before us, we'll
still have a preallocated node that might be used later.
If we then use that node for a new non-root node, it'll still have a
pointer to the old root instead of being zeroed - fix this by zeroing it
in the cmpxchg failure path. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: keystone: Add workaround for Errata #i2037 (AM65x SR 1.0)
Errata #i2037 in AM65x/DRA80xM Processors Silicon Revision 1.0
(SPRZ452D_July 2018_Revised December 2019 [1]) mentions when an
inbound PCIe TLP spans more than two internal AXI 128-byte bursts,
the bus may corrupt the packet payload and the corrupt data may
cause associated applications or the processor to hang.
The workaround for Errata #i2037 is to limit the maximum read
request size and maximum payload size to 128 bytes. Add workaround
for Errata #i2037 here.
The errata and workaround is applicable only to AM65x SR 1.0 and
later versions of the silicon will have this fixed.
[1] -> https://www.ti.com/lit/er/sprz452i/sprz452i.pdf |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: pm80xx: Set phy->enable_completion only when we wait for it
pm8001_phy_control() populates the enable_completion pointer with a stack
address, sends a PHY_LINK_RESET / PHY_HARD_RESET, waits 300 ms, and
returns. The problem arises when a phy control response comes late. After
300 ms the pm8001_phy_control() function returns and the passed
enable_completion stack address is no longer valid. Late phy control
response invokes complete() on a dangling enable_completion pointer which
leads to a kernel crash. |
| In the Linux kernel, the following vulnerability has been resolved:
fsnotify: clear PARENT_WATCHED flags lazily
In some setups directories can have many (usually negative) dentries.
Hence __fsnotify_update_child_dentry_flags() function can take a
significant amount of time. Since the bulk of this function happens
under inode->i_lock this causes a significant contention on the lock
when we remove the watch from the directory as the
__fsnotify_update_child_dentry_flags() call from fsnotify_recalc_mask()
races with __fsnotify_update_child_dentry_flags() calls from
__fsnotify_parent() happening on children. This can lead upto softlockup
reports reported by users.
Fix the problem by calling fsnotify_update_children_dentry_flags() to
set PARENT_WATCHED flags only when parent starts watching children.
When parent stops watching children, clear false positive PARENT_WATCHED
flags lazily in __fsnotify_parent() for each accessed child. |
| In the Linux kernel, the following vulnerability has been resolved:
smack: tcp: ipv4, fix incorrect labeling
Currently, Smack mirrors the label of incoming tcp/ipv4 connections:
when a label 'foo' connects to a label 'bar' with tcp/ipv4,
'foo' always gets 'foo' in returned ipv4 packets. So,
1) returned packets are incorrectly labeled ('foo' instead of 'bar')
2) 'bar' can write to 'foo' without being authorized to write.
Here is a scenario how to see this:
* Take two machines, let's call them C and S,
with active Smack in the default state
(no settings, no rules, no labeled hosts, only builtin labels)
* At S, add Smack rule 'foo bar w'
(labels 'foo' and 'bar' are instantiated at S at this moment)
* At S, at label 'bar', launch a program
that listens for incoming tcp/ipv4 connections
* From C, at label 'foo', connect to the listener at S.
(label 'foo' is instantiated at C at this moment)
Connection succeedes and works.
* Send some data in both directions.
* Collect network traffic of this connection.
All packets in both directions are labeled with the CIPSO
of the label 'foo'. Hence, label 'bar' writes to 'foo' without
being authorized, and even without ever being known at C.
If anybody cares: exactly the same happens with DCCP.
This behavior 1st manifested in release 2.6.29.4 (see Fixes below)
and it looks unintentional. At least, no explanation was provided.
I changed returned packes label into the 'bar',
to bring it into line with the Smack documentation claims. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: stm32/cryp - call finalize with bh disabled
The finalize operation in interrupt mode produce a produces a spinlock
recursion warning. The reason is the fact that BH must be disabled
during this process. |
| In the Linux kernel, the following vulnerability has been resolved:
dma-debug: fix a possible deadlock on radix_lock
radix_lock() shouldn't be held while holding dma_hash_entry[idx].lock
otherwise, there's a possible deadlock scenario when
dma debug API is called holding rq_lock():
CPU0 CPU1 CPU2
dma_free_attrs()
check_unmap() add_dma_entry() __schedule() //out
(A) rq_lock()
get_hash_bucket()
(A) dma_entry_hash
check_sync()
(A) radix_lock() (W) dma_entry_hash
dma_entry_free()
(W) radix_lock()
// CPU2's one
(W) rq_lock()
CPU1 situation can happen when it extending radix tree and
it tries to wake up kswapd via wake_all_kswapd().
CPU2 situation can happen while perf_event_task_sched_out()
(i.e. dma sync operation is called while deleting perf_event using
etm and etr tmc which are Arm Coresight hwtracing driver backends).
To remove this possible situation, call dma_entry_free() after
put_hash_bucket() in check_unmap(). |
| In the Linux kernel, the following vulnerability has been resolved:
pinmux: Use sequential access to access desc->pinmux data
When two client of the same gpio call pinctrl_select_state() for the
same functionality, we are seeing NULL pointer issue while accessing
desc->mux_owner.
Let's say two processes A, B executing in pin_request() for the same pin
and process A updates the desc->mux_usecount but not yet updated the
desc->mux_owner while process B see the desc->mux_usecount which got
updated by A path and further executes strcmp and while accessing
desc->mux_owner it crashes with NULL pointer.
Serialize the access to mux related setting with a mutex lock.
cpu0 (process A) cpu1(process B)
pinctrl_select_state() { pinctrl_select_state() {
pin_request() { pin_request() {
...
....
} else {
desc->mux_usecount++;
desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
if (desc->mux_usecount > 1)
return 0;
desc->mux_owner = owner;
} } |
| In the Linux kernel, the following vulnerability has been resolved:
um: line: always fill *error_out in setup_one_line()
The pointer isn't initialized by callers, but I have
encountered cases where it's still printed; initialize
it in all possible cases in setup_one_line(). |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Handle mailbox timeouts in lpfc_get_sfp_info
The MBX_TIMEOUT return code is not handled in lpfc_get_sfp_info and the
routine unconditionally frees submitted mailbox commands regardless of
return status. The issue is that for MBX_TIMEOUT cases, when firmware
returns SFP information at a later time, that same mailbox memory region
references previously freed memory in its cmpl routine.
Fix by adding checks for the MBX_TIMEOUT return code. During mailbox
resource cleanup, check the mbox flag to make sure that the wait did not
timeout. If the MBOX_WAKE flag is not set, then do not free the resources
because it will be freed when firmware completes the mailbox at a later
time in its cmpl routine.
Also, increase the timeout from 30 to 60 seconds to accommodate boot
scripts requiring longer timeouts. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't BUG_ON on ENOMEM from btrfs_lookup_extent_info() in walk_down_proc()
We handle errors here properly, ENOMEM isn't fatal, return the error. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: clean up our handling of refs == 0 in snapshot delete
In reada we BUG_ON(refs == 0), which could be unkind since we aren't
holding a lock on the extent leaf and thus could get a transient
incorrect answer. In walk_down_proc we also BUG_ON(refs == 0), which
could happen if we have extent tree corruption. Change that to return
-EUCLEAN. In do_walk_down() we catch this case and handle it correctly,
however we return -EIO, which -EUCLEAN is a more appropriate error code.
Finally in walk_up_proc we have the same BUG_ON(refs == 0), so convert
that to proper error handling. Also adjust the error message so we can
actually do something with the information. |
| In the Linux kernel, the following vulnerability has been resolved:
ethtool: fail closed if we can't get max channel used in indirection tables
Commit 0d1b7d6c9274 ("bnxt: fix crashes when reducing ring count with
active RSS contexts") proves that allowing indirection table to contain
channels with out of bounds IDs may lead to crashes. Currently the
max channel check in the core gets skipped if driver can't fetch
the indirection table or when we can't allocate memory.
Both of those conditions should be extremely rare but if they do
happen we should try to be safe and fail the channel change. |
| In the Linux kernel, the following vulnerability has been resolved:
MIPS: cevt-r4k: Don't call get_c0_compare_int if timer irq is installed
This avoids warning:
[ 0.118053] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283
Caused by get_c0_compare_int on secondary CPU.
We also skipped saving IRQ number to struct clock_event_device *cd as
it's never used by clockevent core, as per comments it's only meant
for "non CPU local devices". |
| In the Linux kernel, the following vulnerability has been resolved:
ELF: fix kernel.randomize_va_space double read
ELF loader uses "randomize_va_space" twice. It is sysctl and can change
at any moment, so 2 loads could see 2 different values in theory with
unpredictable consequences.
Issue exactly one load for consistent value across one exec. |
