Linux: >> Linux Kernel >> 2.6.19.5 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req()
While receiving an MST up request message from one thread in
drm_dp_mst_handle_up_req(), the MST topology could be removed from
another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing
mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL.
This could lead to a NULL deref/use-after-free of mst_primary in
drm_dp_mst_handle_up_req().
Avoid the above by holding a reference for mst_primary in
drm_dp_mst_handle_up_req() while it's used.
v2: Fix kfreeing the request if getting an mst_primary reference fails.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-01-11
In the Linux kernel, the following vulnerability has been resolved:
drm/modes: Avoid divide by zero harder in drm_mode_vrefresh()
drm_mode_vrefresh() is trying to avoid divide by zero
by checking whether htotal or vtotal are zero. But we may
still end up with a div-by-zero of vtotal*htotal*...
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
In the Linux kernel, the following vulnerability has been resolved:
ipvs: fix UB due to uninitialized stack access in ip_vs_protocol_init()
Under certain kernel configurations when building with Clang/LLVM, the
compiler does not generate a return or jump as the terminator
instruction for ip_vs_protocol_init(), triggering the following objtool
warning during build time:
vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6()
At runtime, this either causes an oops when trying to load the ipvs
module or a boot-time panic if ipvs is built-in. This same issue has
been reported by the Intel kernel test robot previously.
Digging deeper into both LLVM and the kernel code reveals this to be a
undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer
of 64 chars to store the registered protocol names and leaves it
uninitialized after definition. The function calls strnlen() when
concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE
strnlen() performs an extra step to check whether the last byte of the
input char buffer is a null character (commit 3009f891bb9f ("fortify:
Allow strlen() and strnlen() to pass compile-time known lengths")).
This, together with possibly other configurations, cause the following
IR to be generated:
define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 {
%1 = alloca [64 x i8], align 16
...
14: ; preds = %11
%15 = getelementptr inbounds i8, ptr %1, i64 63
%16 = load i8, ptr %15, align 1
%17 = tail call i1 @llvm.is.constant.i8(i8 %16)
%18 = icmp eq i8 %16, 0
%19 = select i1 %17, i1 %18, i1 false
br i1 %19, label %20, label %23
20: ; preds = %14
%21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) #23
...
23: ; preds = %14, %11, %20
%24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) #24
...
}
The above code calculates the address of the last char in the buffer
(value %15) and then loads from it (value %16). Because the buffer is
never initialized, the LLVM GVN pass marks value %16 as undefined:
%13 = getelementptr inbounds i8, ptr %1, i64 63
br i1 undef, label %14, label %17
This gives later passes (SCCP, in particular) more DCE opportunities by
propagating the undef value further, and eventually removes everything
after the load on the uninitialized stack location:
define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 {
%1 = alloca [64 x i8], align 16
...
12: ; preds = %11
%13 = getelementptr inbounds i8, ptr %1, i64 63
unreachable
}
In this way, the generated native code will just fall through to the
next function, as LLVM does not generate any code for the unreachable IR
instruction and leaves the function without a terminator.
Zero the on-stack buffer to avoid this possible UB.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
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().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't take dev_replace rwsem on task already holding it
Running fstests btrfs/011 with MKFS_OPTIONS="-O rst" to force the usage of
the RAID stripe-tree, we get the following splat from lockdep:
BTRFS info (device sdd): dev_replace from /dev/sdd (devid 1) to /dev/sdb started
============================================
WARNING: possible recursive locking detected
6.11.0-rc3-btrfs-for-next #599 Not tainted
--------------------------------------------
btrfs/2326 is trying to acquire lock:
ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250
but task is already holding lock:
ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&fs_info->dev_replace.rwsem);
lock(&fs_info->dev_replace.rwsem);
*** DEADLOCK ***
May be due to missing lock nesting notation
1 lock held by btrfs/2326:
#0: ffff88810f215c98 (&fs_info->dev_replace.rwsem){++++}-{3:3}, at: btrfs_map_block+0x39f/0x2250
stack backtrace:
CPU: 1 UID: 0 PID: 2326 Comm: btrfs Not tainted 6.11.0-rc3-btrfs-for-next #599
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
<TASK>
dump_stack_lvl+0x5b/0x80
__lock_acquire+0x2798/0x69d0
? __pfx___lock_acquire+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
lock_acquire+0x19d/0x4a0
? btrfs_map_block+0x39f/0x2250
? __pfx_lock_acquire+0x10/0x10
? find_held_lock+0x2d/0x110
? lock_is_held_type+0x8f/0x100
down_read+0x8e/0x440
? btrfs_map_block+0x39f/0x2250
? __pfx_down_read+0x10/0x10
? do_raw_read_unlock+0x44/0x70
? _raw_read_unlock+0x23/0x40
btrfs_map_block+0x39f/0x2250
? btrfs_dev_replace_by_ioctl+0xd69/0x1d00
? btrfs_bio_counter_inc_blocked+0xd9/0x2e0
? __kasan_slab_alloc+0x6e/0x70
? __pfx_btrfs_map_block+0x10/0x10
? __pfx_btrfs_bio_counter_inc_blocked+0x10/0x10
? kmem_cache_alloc_noprof+0x1f2/0x300
? mempool_alloc_noprof+0xed/0x2b0
btrfs_submit_chunk+0x28d/0x17e0
? __pfx_btrfs_submit_chunk+0x10/0x10
? bvec_alloc+0xd7/0x1b0
? bio_add_folio+0x171/0x270
? __pfx_bio_add_folio+0x10/0x10
? __kasan_check_read+0x20/0x20
btrfs_submit_bio+0x37/0x80
read_extent_buffer_pages+0x3df/0x6c0
btrfs_read_extent_buffer+0x13e/0x5f0
read_tree_block+0x81/0xe0
read_block_for_search+0x4bd/0x7a0
? __pfx_read_block_for_search+0x10/0x10
btrfs_search_slot+0x78d/0x2720
? __pfx_btrfs_search_slot+0x10/0x10
? lock_is_held_type+0x8f/0x100
? kasan_save_track+0x14/0x30
? __kasan_slab_alloc+0x6e/0x70
? kmem_cache_alloc_noprof+0x1f2/0x300
btrfs_get_raid_extent_offset+0x181/0x820
? __pfx_lock_acquire+0x10/0x10
? __pfx_btrfs_get_raid_extent_offset+0x10/0x10
? down_read+0x194/0x440
? __pfx_down_read+0x10/0x10
? do_raw_read_unlock+0x44/0x70
? _raw_read_unlock+0x23/0x40
btrfs_map_block+0x5b5/0x2250
? __pfx_btrfs_map_block+0x10/0x10
scrub_submit_initial_read+0x8fe/0x11b0
? __pfx_scrub_submit_initial_read+0x10/0x10
submit_initial_group_read+0x161/0x3a0
? lock_release+0x20e/0x710
? __pfx_submit_initial_group_read+0x10/0x10
? __pfx_lock_release+0x10/0x10
scrub_simple_mirror.isra.0+0x3eb/0x580
scrub_stripe+0xe4d/0x1440
? lock_release+0x20e/0x710
? __pfx_scrub_stripe+0x10/0x10
? __pfx_lock_release+0x10/0x10
? do_raw_read_unlock+0x44/0x70
? _raw_read_unlock+0x23/0x40
scrub_chunk+0x257/0x4a0
scrub_enumerate_chunks+0x64c/0xf70
? __mutex_unlock_slowpath+0x147/0x5f0
? __pfx_scrub_enumerate_chunks+0x10/0x10
? bit_wait_timeout+0xb0/0x170
? __up_read+0x189/0x700
? scrub_workers_get+0x231/0x300
? up_write+0x490/0x4f0
btrfs_scrub_dev+0x52e/0xcd0
? create_pending_snapshots+0x230/0x250
? __pfx_btrfs_scrub_dev+0x10/0x10
btrfs_dev_replace_by_ioctl+0xd69/0x1d00
? lock_acquire+0x19d/0x4a0
? __pfx_btrfs_dev_replace_by_ioctl+0x10/0x10
?
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
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;
} }
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-11
In the Linux kernel, the following vulnerability has been resolved:
ACPI: x86: Add adev NULL check to acpi_quirk_skip_serdev_enumeration()
acpi_dev_hid_match() does not check for adev == NULL, dereferencing
it unconditional.
Add a check for adev being NULL before calling acpi_dev_hid_match().
At the moment acpi_quirk_skip_serdev_enumeration() is never called with
a controller_parent without an ACPI companion, but better safe than sorry.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-08
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Adding array index check to prevent memory corruption
[Why & How]
Array indices out of bound caused memory corruption. Adding checks to
ensure that array index stays in bound.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-01-08
In the Linux kernel, the following vulnerability has been resolved:
MIPS: Loongson64: DTS: Really fix PCIe port nodes for ls7a
Fix the dtc warnings:
arch/mips/boot/dts/loongson/ls7a-pch.dtsi:68.16-416.5: Warning (interrupt_provider): /bus@10000000/pci@1a000000: '#interrupt-cells' found, but node is not an interrupt provider
arch/mips/boot/dts/loongson/ls7a-pch.dtsi:68.16-416.5: Warning (interrupt_provider): /bus@10000000/pci@1a000000: '#interrupt-cells' found, but node is not an interrupt provider
arch/mips/boot/dts/loongson/loongson64g_4core_ls7a.dtb: Warning (interrupt_map): Failed prerequisite 'interrupt_provider'
And a runtime warning introduced in commit 045b14ca5c36 ("of: WARN on
deprecated #address-cells/#size-cells handling"):
WARNING: CPU: 0 PID: 1 at drivers/of/base.c:106 of_bus_n_addr_cells+0x9c/0xe0
Missing '#address-cells' in /bus@10000000/pci@1a000000/pci_bridge@9,0
The fix is similar to commit d89a415ff8d5 ("MIPS: Loongson64: DTS: Fix PCIe
port nodes for ls7a"), which has fixed the issue for ls2k (despite its
subject mentions ls7a).
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-08