In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: do not pass a stopped vif to the driver in .get_txpower
Avoid potentially crashing in the driver because of uninitialized private data
In the Linux kernel, the following vulnerability has been resolved:
cxl/port: Fix use-after-free, permit out-of-order decoder shutdown
In support of investigating an initialization failure report [1],
cxl_test was updated to register mock memory-devices after the mock
root-port/bus device had been registered. That led to cxl_test crashing
with a use-after-free bug with the following signature:
cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1
cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1
cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0
1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1
[..]
cxld_unregister: cxl decoder14.0:
cxl_region_decode_reset: cxl_region region3:
mock_decoder_reset: cxl_port port3: decoder3.0 reset
2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1
cxl_endpoint_decoder_release: cxl decoder14.0:
[..]
cxld_unregister: cxl decoder7.0:
3) cxl_region_decode_reset: cxl_region region3:
Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI
[..]
RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core]
[..]
Call Trace:
<TASK>
cxl_region_decode_reset+0x69/0x190 [cxl_core]
cxl_region_detach+0xe8/0x210 [cxl_core]
cxl_decoder_kill_region+0x27/0x40 [cxl_core]
cxld_unregister+0x5d/0x60 [cxl_core]
At 1) a region has been established with 2 endpoint decoders (7.0 and
14.0). Those endpoints share a common switch-decoder in the topology
(3.0). At teardown, 2), decoder14.0 is the first to be removed and hits
the "out of order reset case" in the switch decoder. The effect though
is that region3 cleanup is aborted leaving it in-tact and
referencing decoder14.0. At 3) the second attempt to teardown region3
trips over the stale decoder14.0 object which has long since been
deleted.
The fix here is to recognize that the CXL specification places no
mandate on in-order shutdown of switch-decoders, the driver enforces
in-order allocation, and hardware enforces in-order commit. So, rather
than fail and leave objects dangling, always remove them.
In support of making cxl_region_decode_reset() always succeed,
cxl_region_invalidate_memregion() failures are turned into warnings.
Crashing the kernel is ok there since system integrity is at risk if
caches cannot be managed around physical address mutation events like
CXL region destruction.
A new device_for_each_child_reverse_from() is added to cleanup
port->commit_end after all dependent decoders have been disabled. In
other words if decoders are allocated 0->1->2 and disabled 1->2->0 then
port->commit_end only decrements from 2 after 2 has been disabled, and
it decrements all the way to zero since 1 was disabled previously.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential deadlock with newly created symlinks
Syzbot reported that page_symlink(), called by nilfs_symlink(), triggers
memory reclamation involving the filesystem layer, which can result in
circular lock dependencies among the reader/writer semaphore
nilfs->ns_segctor_sem, s_writers percpu_rwsem (intwrite) and the
fs_reclaim pseudo lock.
This is because after commit 21fc61c73c39 ("don't put symlink bodies in
pagecache into highmem"), the gfp flags of the page cache for symbolic
links are overwritten to GFP_KERNEL via inode_nohighmem().
This is not a problem for symlinks read from the backing device, because
the __GFP_FS flag is dropped after inode_nohighmem() is called. However,
when a new symlink is created with nilfs_symlink(), the gfp flags remain
overwritten to GFP_KERNEL. Then, memory allocation called from
page_symlink() etc. triggers memory reclamation including the FS layer,
which may call nilfs_evict_inode() or nilfs_dirty_inode(). And these can
cause a deadlock if they are called while nilfs->ns_segctor_sem is held:
Fix this issue by dropping the __GFP_FS flag from the page cache GFP flags
of newly created symlinks in the same way that nilfs_new_inode() and
__nilfs_read_inode() do, as a workaround until we adopt nofs allocation
scope consistently or improve the locking constraints.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix kernel bug due to missing clearing of checked flag
Syzbot reported that in directory operations after nilfs2 detects
filesystem corruption and degrades to read-only,
__block_write_begin_int(), which is called to prepare block writes, may
fail the BUG_ON check for accesses exceeding the folio/page size,
triggering a kernel bug.
This was found to be because the "checked" flag of a page/folio was not
cleared when it was discarded by nilfs2's own routine, which causes the
sanity check of directory entries to be skipped when the directory
page/folio is reloaded. So, fix that.
This was necessary when the use of nilfs2's own page discard routine was
applied to more than just metadata files.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix use-after-free of block device file in __btrfs_free_extra_devids()
Mounting btrfs from two images (which have the same one fsid and two
different dev_uuids) in certain executing order may trigger an UAF for
variable 'device->bdev_file' in __btrfs_free_extra_devids(). And
following are the details:
1. Attach image_1 to loop0, attach image_2 to loop1, and scan btrfs
devices by ioctl(BTRFS_IOC_SCAN_DEV):
/ btrfs_device_1 → loop0
fs_device
\ btrfs_device_2 → loop1
2. mount /dev/loop0 /mnt
btrfs_open_devices
btrfs_device_1->bdev_file = btrfs_get_bdev_and_sb(loop0)
btrfs_device_2->bdev_file = btrfs_get_bdev_and_sb(loop1)
btrfs_fill_super
open_ctree
fail: btrfs_close_devices // -ENOMEM
btrfs_close_bdev(btrfs_device_1)
fput(btrfs_device_1->bdev_file)
// btrfs_device_1->bdev_file is freed
btrfs_close_bdev(btrfs_device_2)
fput(btrfs_device_2->bdev_file)
3. mount /dev/loop1 /mnt
btrfs_open_devices
btrfs_get_bdev_and_sb(&bdev_file)
// EIO, btrfs_device_1->bdev_file is not assigned,
// which points to a freed memory area
btrfs_device_2->bdev_file = btrfs_get_bdev_and_sb(loop1)
btrfs_fill_super
open_ctree
btrfs_free_extra_devids
if (btrfs_device_1->bdev_file)
fput(btrfs_device_1->bdev_file) // UAF !
Fix it by setting 'device->bdev_file' as 'NULL' after closing the
btrfs_device in btrfs_close_one_device().
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: pass u64 to ocfs2_truncate_inline maybe overflow
Syzbot reported a kernel BUG in ocfs2_truncate_inline. There are two
reasons for this: first, the parameter value passed is greater than
ocfs2_max_inline_data_with_xattr, second, the start and end parameters of
ocfs2_truncate_inline are "unsigned int".
So, we need to add a sanity check for byte_start and byte_len right before
ocfs2_truncate_inline() in ocfs2_remove_inode_range(), if they are greater
than ocfs2_max_inline_data_with_xattr return -EINVAL.
In the Linux kernel, the following vulnerability has been resolved:
nvmet-auth: assign dh_key to NULL after kfree_sensitive
ctrl->dh_key might be used across multiple calls to nvmet_setup_dhgroup()
for the same controller. So it's better to nullify it after release on
error path in order to avoid double free later in nvmet_destroy_auth().
Found by Linux Verification Center (linuxtesting.org) with Svace.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: Fix a bug while setting up Level-2 PBL pages
Avoid memory corruption while setting up Level-2 PBL pages for the non MR
resources when num_pages > 256K.
There will be a single PDE page address (contiguous pages in the case of >
PAGE_SIZE), but, current logic assumes multiple pages, leading to invalid
memory access after 256K PBL entries in the PDE.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: Add a check for memory allocation
__alloc_pbl() can return error when memory allocation fails.
Driver is not checking the status on one of the instances.