kernel-4.18.0-553.173.1.el8_10

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

* kernel: openvswitch: defer tunnel netdev_put to RCU release (CVE-2026-31678)
* kernel: ipv6: validate extension header length before copying to cmsg (CVE-2026-63920)
* kernel: drm/amd/display: set new_stream to NULL after release (CVE-2026-68236)
* kernel: drm/dp/mst: fix buffer overflows in sideband chunk accumulation (CVE-2026-68278)
* kernel: wifi: mac80211: defer link RX stats percpu free to RCU (CVE-2026-68409)
* kernel: drm/amdgpu/vce: fix integer overflow in image size (CVE-2026-68108)
* kernel: cifs: validate DFS referral string offsets (CVE-2026-72318)
* kernel: drm/vmwgfx: use check_add_overflow for shader size+offset bound (CVE-2026-80887)
* kernel: drm/amdkfd: Add TLB flush after MES queue eviction/suspension (CVE-2026-89811)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

CVE-2026-31678
In the Linux kernel, the following vulnerability has been resolved: openvswitch: defer tunnel netdev_put to RCU release ovs_netdev_tunnel_destroy() may run after NETDEV_UNREGISTER already detached the device. Dropping the netdev reference in destroy can race with concurrent readers that still observe vport->dev. Do not release vport->dev in ovs_netdev_tunnel_destroy(). Instead, let vport_netdev_free() drop the reference from the RCU callback, matching the non-tunnel destroy path and avoiding additional synchronization under RTNL.
CVE-2026-63920
In the Linux kernel, the following vulnerability has been resolved: ipv6: validate extension header length before copying to cmsg ip6_datagram_recv_specific_ctl() builds IPV6_{HOPOPTS,DSTOPTS,RTHDR} cmsgs (and their IPV6_2292* legacy counterparts) by trusting the on-wire hdrlen byte (ptr[1]) when computing the put_cmsg() length. The length was validated only at parse time (ipv6_parse_hopopts(), etc.). An nftables payload-write expression can rewrite hdrlen after parsing and before the skb reaches recvmsg; the write itself is in-bounds but put_cmsg() then reads up to ((hdrlen+1) << 3) = 2040 bytes from an 8-byte header. nftables is reachable from an unprivileged user namespace, so this is an unprivileged slab-out-of-bounds read: BUG: KASAN: slab-out-of-bounds in put_cmsg+0x3ac/0x540 put_cmsg+0x3ac/0x540 udpv6_recvmsg+0xca0/0x1250 sock_recvmsg+0xdf/0x190 ____sys_recvmsg+0x1b1/0x620 Add ipv6_get_exthdr_len() which validates that at least two bytes are accessible before reading the hdrlen field, then checks the computed length against skb_tail_pointer(skb), returning 0 on failure. Extension headers are kept in the linear skb area by pskb_may_pull() during input, so skb_tail_pointer() is the correct bound. Use ipv6_get_exthdr_len() at all non-AH call sites: the five standalone cmsg blocks (HbH, 2292HbH, 2292DSTOPTS x2, 2292RTHDR) and the three standard cases in the extension-header walk loop (DSTOPTS, ROUTING, default). AH retains an inline bounds check because its length formula differs ((ptr[1]+2)<<2). The walk loop also gets a pre-read bounds check at the top to validate ptr before any case accesses ptr[0] or ptr[1]. When the walk loop detects a corrupted header, return from the function instead of continuing to process later socket options.
CVE-2026-68108
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vce: fix integer overflow in image size Fix a security vulnerability where malicious VCE command streams with oversized dimensions (e.g. 65536×65536) cause 32-bit integer overflow, wrapping the calculated buffer size to 0. This bypasses validation and allows GPU firmware to perform out-of-bound memory access. The fix uses 64-bit arithmetic to detect overflow and rejects invalid dimensions before they reach the hardware. V2: remove redundant check V3: modify max height value V4: remove size64 (cherry picked from commit cbe408dba581755ad1279a487ec786d8927d778d)
CVE-2026-68236
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: set new_stream to NULL after release In dm_update_crtc_state(), the skip_modeset path releases new_stream via dc_stream_release() but does not set the pointer to NULL. If a later error (e.g., color management failure) triggers the fail label, the error path calls dc_stream_release() again on the same dangling pointer, causing a double release and potential use-after-free. Fix this by setting new_stream to NULL after the initial release. (cherry picked from commit 99f3af19073b3ddbfd96e789124cce12c4277b28)
CVE-2026-68278
In the Linux kernel, the following vulnerability has been resolved: drm/dp/mst: fix buffer overflows in sideband chunk accumulation drm_dp_sideband_append_payload() has three related bugs when processing device-provided sideband reply data: 1. Zero-length curchunk_len underflow: msg_len is a 6-bit field taken directly from the DP sideband header. If a device sends msg_len=0, curchunk_len is set to zero. The condition (curchunk_idx >= curchunk_len) is immediately true, and curchunk_len-1 wraps to 255 (u8 underflow). drm_dp_msg_data_crc4() reads 255 bytes from chunk[48], then memcpy() writes 255 bytes into msg[], both far out of bounds. 2. chunk[48] overflow: curchunk_len can reach 63 (6-bit field). chunk[] is only 48 bytes. Multi-iteration payload assembly appends 16-byte blocks until curchunk_idx reaches curchunk_len, writing up to 15 bytes past the end of chunk[] into msg[]. 3. msg[256] overflow: each chunk contributes (curchunk_len-1) bytes to msg[]. No check ensures curlen + (curchunk_len-1) stays within msg[256], so the memcpy can spill into adjacent struct fields. All three are reachable from any DP MST device that can forge sideband reply messages on a physical connection.
CVE-2026-68409
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: defer link RX stats percpu free to RCU sta_remove_link() frees a removed MLO link's RX stats percpu buffer right away, but defers only the link container to RCU: sta_info_free_link(&alloc->info); kfree_rcu(alloc, rcu_head); The RX fast path reads link_sta under rcu_read_lock and writes the percpu stats. A reader that resolved link_sta before the removal keeps the pointer. The container stays alive from the kfree_rcu, so the read still works. But the percpu block it points to is already freed. This needs uses_rss. That is when pcpu_rx_stats exists. The full STA teardown frees the deflink stats only after synchronize_net(). The link removal path had no such barrier. The race is hard to win in practice, but the free should still wait for RCU. Free the link together with its data from a single RCU callback, so the percpu block is reclaimed only after readers drain.
CVE-2026-72318
In the Linux kernel, the following vulnerability has been resolved: cifs: validate DFS referral string offsets parse_dfs_referrals() validates that the response header and referral array fit in the received buffer, but each referral also contains string offsets supplied by the server. Those offsets are used to compute the DfsPath and NetworkAddress string pointers without checking whether they still point inside the response buffer. A malformed referral can therefore make the computed pointer exceed the end of the buffer. The resulting negative max_len is then passed to cifs_strndup_from_utf16(), and the non-Unicode path forwards it to kstrndup() as a size_t, allowing strnlen() to read out of bounds. Validate each string offset before deriving the string pointer.
CVE-2026-80887
In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: use check_add_overflow for shader size+offset bound vmw_shader_define() validates the user-supplied shader window against its backing buffer with (u64)buffer->tbo.base.size < (u64)size + (u64)offset drm_vmw_shader_create_arg::offset is __u64 in the uapi; when it is near U64_MAX the unsigned addition wraps and the resulting tiny value passes the check. The unbounded offset is then stored in res->guest_memory_offset and forwarded to host SVGA shader-create commands. Use check_add_overflow() to detect the wrap and compare the resulting endpoint against the buffer size.
CVE-2026-89811
In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Add TLB flush after MES queue eviction/suspension MES (Micro Engine Scheduler) does not perform heavy-weight TLB invalidation after unmapping queues, unlike HWS which does this automatically. This causes a race condition where in-flight DMA descriptors can access memory that has been unmapped, leading to page faults and GPU queue hangs during SVM page migration. The issue manifests as KFDSVMRangeTest.MultiThreadMigrationTest failures on gfx1151 (Strix Point) with XNACK mode 1 enabled - the GPU compute queue hangs with packets submitted but never consumed. Add kfd_flush_tlb() calls after MES queue removal in two locations: - evict_process_queues_cpsch(): after all queues removed during eviction - suspend_queues(): after debug/criu queue suspension (with mem_fence barrier) This ensures all in-flight memory accesses from unmapped queues are flushed before memory is freed or migrated. (cherry picked from commit f5c4f88e0f9c45a8fb9dfac0c1df726c95e41b77)