In the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: Check write tracking in all address spaces
kvm_gfn_is_write_tracked() checks only the supplied memslot, but page
tracking is per-address-space and shadow pages are shared across all
address spaces. With SMM, a GFN can therefore be write-tracked in one
address space and appear untracked through the other.
Check the supplied slot first, then the slot for the other address space.
This ensures all callers honor write tracking regardless of the active
address space. In particular, it prevents mmu_try_to_unsync_pages() from
marking an upper-level shadow page unsync and eventually triggering the
BUG in pte_list_remove().
[invert direction of the conditional. - Paolo]
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix mismatched free of HalData in rtw_sdio_if1_init()
padapter->HalData is allocated via vzalloc(), but incorrectly freed
using kfree() in the rtw_sdio_if1_init() error path. Using kfree() to
release this vmalloc-backed buffer can lead to memory corruption.
Use rtw_hal_data_deinit() to pair the free correctly and free
HalData with vfree().
The bug was first flagged by an experimental static analysis tool we
are developing for kernel memory-management bugs. Manual inspection
confirms that the issue is still present in current mainline.
An x86_64 allyesconfig build showed no new warnings. As we do not have
suitable RTL8723BS SDIO hardware to test with, no runtime testing was
able to be performed.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/srpt: Fix srpt_alloc_rw_ctxs() unwind counters
When srpt_alloc_rw_ctxs() fails partway through a multi-buffer indirect
descriptor, the unwind path destroys RDMA contexts but leaves stale
n_rw_ctx and n_rdma values (and a dangling rw_ctxs pointer). Later
sq_wr_avail accounting in srpt_queue_response() or srpt_write_pending()
can then subtract the wrong number of send queue credits.
Reset the counters and clear rw_ctxs after freeing the heap
allocation before returning an error.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix xmit_frame/xmit_buf leaks on mgnt-frame error paths
issue_beacon(), issue_probersp() and issue_asocrsp() obtain a management
xmit_frame together with its xmit_buf from the driver's fixed-size
management-TX pools via alloc_mgtxmitframe(). On the normal path the frame
is handed to dump_mgntframe(), which transfers ownership and eventually
returns both objects to their pools (the frame and, for beacons, the buf
in rtl8723bs_mgnt_xmit(); other bufs via the pending-xmitbuf/TX-completion
path).
Several error/edge paths return early after a successful
alloc_mgtxmitframe() but before dump_mgntframe(), so ownership is never
transferred and neither object is freed:
- issue_beacon(): beacon larger than 512 bytes
- issue_probersp(): cur_network->ie_length > MAX_IE_SZ
- issue_probersp(): kzalloc() of the SSID scratch buffer fails
- issue_asocrsp(): pkt_type is neither ASSOCRSP nor REASSOCRSP
Because alloc_mgtxmitframe() removes the frame and buf from their free
lists (list_del_init) without placing them on any pending list, an
orphaned pair is on no list and referenced by nobody, so it is only
reclaimed at driver teardown. Repeated hits progressively exhaust the
management-TX pools until alloc_mgtxmitframe() returns NULL and the
interface can no longer send beacons or probe/assoc responses.
Free the frame and buffer on these paths, matching the existing correct
error handling in issue_assocreq().
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Recover HW before retire hung submit
During recovery, it is not safe to retire the hung submit before we
recover the GPU. Retiring the submit triggers BO free and that can
result in GPU pagefaults since the GPU may be actively accessing those
BOs.
To fix this, retire the submits after gpu recovery is complete in
recover_worker().
Patchwork: https://patchwork.freedesktop.org/patch/730655/
In the Linux kernel, the following vulnerability has been resolved:
can: bcm: switch timer to HRTIMER_MODE_SOFT and remove hrtimer_tasklet
This patch switches the timer to HRTIMER_MODE_SOFT, which executed the
timer callback in softirq context and removes the hrtimer_tasklet.
In the Linux kernel, the following vulnerability has been resolved:
6lowpan: fix NHC entry use-after-free on error path
lowpan_nhc_do_uncompression() looks up an NHC descriptor while holding
lowpan_nhc_lock. If the descriptor has no uncompress callback, the error
path drops the lock before printing nhc->name.
lowpan_nhc_del() removes descriptors under the same lock and then relies
on synchronize_net() before the owning module can be unloaded. That only
waits for net RX RCU readers. lowpan_header_decompress() is also exported
and can be reached from callers that are not necessarily covered by the net
core RX critical section, for example the Bluetooth 6LoWPAN L2CAP receive
path.
This leaves a race where one task drops lowpan_nhc_lock in the error path,
another task unregisters and frees the matching descriptor after
synchronize_net() returns, and the first task then dereferences nhc->name
for the warning.
With the post-unlock window widened, KASAN reports:
BUG: KASAN: slab-use-after-free in lowpan_nhc_do_uncompression+0x1f4/0x220
Read of size 8
lowpan_nhc_do_uncompression
lowpan_header_decompress
Fix this by printing the warning before dropping lowpan_nhc_lock, so the
descriptor name is read while unregister is still excluded. The malformed
packet is still rejected with -ENOTSUPP.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix OOB read in OnAssocRsp() IE loop
The IE parsing loop in OnAssocRsp() advances by (pIE->length + 2) each
iteration but only guards on i < pkt_len. When a malicious AP sends an
AssocResponse whose last IE has only one byte remaining in the frame
(the element_id byte lands at pkt_len-1), the loop reads pIE->length
from pframe[pkt_len], which is one byte past the allocated receive buffer.
Additionally, even when the header bytes are in bounds, pIE->length
itself can extend the data window beyond pkt_len, silently passing a
truncated IE to the handler functions.
Add two guards at the top of the loop body:
1. Break if fewer than sizeof(*pIE) bytes remain (can't read header).
2. Break if the IE's declared data extends past pkt_len.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix WEP length underflow and OOB read in OnAuth()
OnAuth() has two bugs in the shared-key authentication path.
When the Privacy bit is set, rtw_wep_decrypt() is called without
verifying that the frame is long enough to contain a valid WEP IV and
ICV. Inside rtw_wep_decrypt(), length is computed as:
length = len - WLAN_HDR_A3_LEN - iv_len
and then passed as (length - 4) to crc32_le(). If len is less than
WLAN_HDR_A3_LEN + iv_len + icv_len (32 bytes), length - 4 is negative
and, after the implicit cast to size_t, causes crc32_le() to read far
beyond the frame buffer. Add a minimum length check before accessing
the IV field and calling the decryption path.
When processing a seq=3 response, rtw_get_ie() stores the Challenge
Text IE length in ie_len, but the subsequent memcmp() always reads 128
bytes regardless of ie_len. IEEE 802.11 mandates a challenge text of
exactly 128 bytes; reject any IE whose length field differs, matching
the check already applied to OnAuthClient().
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix heap buffer overflow in rtw_cfg80211_set_wpa_ie()
supplicant_ie is a 256-byte array in struct security_priv. The WPA and
WPA2 IE copy paths use:
memcpy(padapter->securitypriv.supplicant_ie, &pwpa[0], wpa_ielen + 2);
where wpa_ielen is the raw IE length field (u8, 0-255). When a local user
supplies a connect request via nl80211 with a crafted WPA IE of length 255,
wpa_ielen + 2 equals 257, overflowing the 256-byte buffer by one byte into
the adjacent last_mic_err_time field.
rtw_parse_wpa_ie() does not prevent this: its length consistency check
compares *(wpa_ie+1) against (u8)(wpa_ie_len-2), which is (u8)(255) == 255
when wpa_ie_len = 257, so the check passes silently.
Add explicit bounds checks for both the WPA and WPA2 paths before the
memcpy, rejecting any IE whose total size (wpa_ielen + 2) exceeds the
supplicant_ie buffer.