Sicherheitslücken in linux-lowlatency-hwe-5.15 · Seite 115

fs: refuse O_TMPFILE creation with an unmapped fsuid or fsgid

In the Linux kernel, the following vulnerability has been resolved: fs: refuse O_TMPFILE creation with an unmapped fsuid or fsgid vfs_tmpfile() never checked that the caller's fsuid and fsgid map into the filesystem. On an idmapped mount whose idmapping does not cover the caller's fs{u,g}id, the ->tmpfile() instance initializes the new inode through inode_init_owner(), where mapped_fsuid()/mapped_fsgid() return INVALID_UID/INVALID_GID, and the tmpfile ends up owned by (uid_t)-1. Every other creation path already refuses this: may_o_create() (O_CREAT) and may_create_dentry() (mkdir, mknod, symlink, link) bail out with -EOVERFLOW via fsuidg

afs: Fix error code in afs_extract_vl_addrs()

In the Linux kernel, the following vulnerability has been resolved: afs: Fix error code in afs_extract_vl_addrs() The error codes on these paths are only set on the first iteration through the loop. Set the correct error code on every iteration.

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afs: Fix misplaced inc of net->cells_outstanding

In the Linux kernel, the following vulnerability has been resolved: afs: Fix misplaced inc of net->cells_outstanding Fix net->cells_outstanding being incremented before the check for failure of idr_alloc_cyclic(), leaving the count incremented on error.

afs: Fix reinitialisation of the inode, in particular ->lock_work

In the Linux kernel, the following vulnerability has been resolved: afs: Fix reinitialisation of the inode, in particular ->lock_work It seems that initalising afs_vnode::lock_work a single time in the slab's init function isn't sufficient for work_structs. This results in the DEBUG_OBJECTS debugging stuff producing a warning occasionally when running the generic/131 xfstest: ODEBUG: activate not available (active state 0) object: 0000000016d8760f object type: work_struct hint: afs_lock_work+0x0/0x220 WARNING: lib/debugobjects.c:629 at debug_print_object+0x4b/0x90, CPU#3: locktest/7695 ... CPU: 3 UID: 0 PID: 7695 Comm: locktest Tainte

afs: Fix callback service message parsers to pass through -EAGAIN

In the Linux kernel, the following vulnerability has been resolved: afs: Fix callback service message parsers to pass through -EAGAIN The AFS filesystem client uses an rxrpc server to listen for callback notifications. Each callback call type handler has a delivery function that parses the incoming request stream, and this should return -EAGAIN the last packet hasn't yet been seen, but all currently queued received data is consumed. afs_extract_data() does this, but the -EAGAIN return is switched to 0 inadvertantly Fix callback service message parsers to pass through -EAGAIN

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afs: Fix missing NULL pointer check in afs_break_some_callbacks()

In the Linux kernel, the following vulnerability has been resolved: afs: Fix missing NULL pointer check in afs_break_some_callbacks() Fix afs_break_some_callbacks() to check to see if afs_lookup_volume_rcu() returned NULL (e.g. the specified volume is unknown).

afs: Fix the volume AFS_VOLUME_RM_TREE is set on

In the Linux kernel, the following vulnerability has been resolved: afs: Fix the volume AFS_VOLUME_RM_TREE is set on Fix afs_insert_volume_into_cell() to set AFS_VOLUME_RM_TREE on the volume replaced, not the new volume, as it's now removed from the cell's volume tree. This will cause the old volume to be removed from the tree twice and the new volume never to be removed.

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minix: avoid overflow in bitmap block count calculation

In the Linux kernel, the following vulnerability has been resolved: minix: avoid overflow in bitmap block count calculation minix_check_superblock() uses minix_blocks_needed() to verify that the on-disk imap and zmap block counts are large enough for the advertised inode and zone counts. The helper currently performs DIV_ROUND_UP() in unsigned int arithmetic. A Minix v3 image can set s_ninodes or s_zones near UINT_MAX so the addition inside DIV_ROUND_UP() wraps to zero. That makes a zero imap/zmap block count look valid, after which minix_fill_super() can dereference s_imap[0] or s_zmap[0] even though no bitmap buffers were allocated. Imp

gue: validate REMCSUM private option length

In the Linux kernel, the following vulnerability has been resolved: gue: validate REMCSUM private option length GUE private flags can indicate that remote checksum offload metadata is present. The private flags field itself is accounted for by guehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even when GUE_PFLAG_REMCSUM is set. This lets a packet with only the private flags field pass validate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum() read the missing REMCSUM start/offset fields from the following bytes. Account for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that malformed packets are reject

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netfilter: xt_u32: reject invalid shift counts

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_u32: reject invalid shift counts u32_match_it() executes rule-supplied shift operands on a 32-bit value. A malformed u32 rule can provide a shift count of 32 or more, triggering an undefined shift out-of-bounds during packet evaluation. Validate XT_U32_LEFTSH and XT_U32_RIGHTSH operands in u32_mt_checkentry() and reject malformed rules before they reach the packet path.

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netfilter: xt_rateest: fix u64 truncation in xt_rateest_mt()

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_rateest: fix u64 truncation in xt_rateest_mt() On links faster than ~34 Gbps, where byte rate may exceed 2^32-1 (~ 4.3 GBps), the comparison result becomes incorrect because the truncated value no longer reflects the actual estimator rate. Fix by changing the local variables to u64.

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netfilter: ip6tables: mark malformed IPv6 extension headers for hotdrop

In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6tables: mark malformed IPv6 extension headers for hotdrop The ah, hbh and rt matches check that the fixed extension header is present, then use the header length field to derive the advertised extension header length for matching. For the ah match, add the missing advertised-length check. For hbh and rt, update the existing advertised-length checks. In all three cases, set hotdrop to true before returning false when the advertised extension header length exceeds the available skb data. Returning false treats the packet as a rule mismatch. Set hotdrop to true

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netfilter: xt_connmark: reject invalid shift parameters

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_connmark: reject invalid shift parameters Revision 2 of the CONNMARK target accepts user-controlled shift parameters and applies them to 32-bit mark values in connmark_tg_shift(). A shift_bits value of 32 or more triggers an undefined-shift bug when the rule is evaluated. Invalid shift_dir values are also accepted and silently fall back to the left-shift path. Reject invalid revision-2 shift parameters in connmark_tg_check() so malformed rules fail at installation time, before they can reach the packet path.

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net/mlx5e: Fix HV VHCA stats agent registration race

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix HV VHCA stats agent registration race mlx5e_hv_vhca_stats_create() registers the stats agent through mlx5_hv_vhca_agent_create(). The helper publishes the agent in hv_vhca->agents[type] under agents_lock and immediately schedules an asynchronous control invalidation on the HV VHCA workqueue before returning to mlx5e. The asynchronous invalidation invokes the control agent's invalidate callback, which reads the hypervisor control block and forwards the command to mlx5e_hv_vhca_stats_control(). That callback may either: - call cancel_delayed_work_sync(&priv

qede: fix off-by-one in BD ring consumption on build_skb failure

In the Linux kernel, the following vulnerability has been resolved: qede: fix off-by-one in BD ring consumption on build_skb failure qede_rx_build_skb() and qede_tpa_rx_build_skb() do not check for a NULL return from qede_build_skb(). When it returns NULL under memory pressure, the functions still consume a BD from the ring before returning NULL. The callers then recycle additional BDs, resulting in one extra BD being consumed (off-by-one). This desynchronizes the BD ring, which can corrupt DMA page reference counts and lead to SLUB freelist corruption. Commit 4e910dbe3650 ("qede: confirm skb is allocated before using") added a NULL check

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net/sched: act_pedit: fix TOCTOU heap OOB write in tc offload

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_pedit: fix TOCTOU heap OOB write in tc offload There is a TOCTOU race condition in flower lockless approach between sizing a flow_rule buffer and filling it. [email protected] reports: The cls_flower classifier operates with TCF_PROTO_OPS_DOIT_UNLOCKED (fl_change runs without RTNL), while RTM_NEWACTION holds RTNL, so the independent locking domains make the race reachable in practice. KASAN confirms: BUG: KASAN: slab-out-of-bounds in tcf_pedit_offload_act_setup+0x81b/0x930 Write of size 4 at addr ffff888001f27520 by task poc-toctou/312 The

Bluetooth: 6lowpan: avoid untracked enable work

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: 6lowpan: avoid untracked enable work lowpan_enable_set() allocates a temporary work item and schedules do_enable_set() on system_wq, then returns to debugfs. The debugfs active operation has ended at that point, but the worker still executes module text and manipulates enable_6lowpan and listen_chan. bt_6lowpan_exit() removes the debugfs files and immediately closes and puts listen_chan. It has no pointer to the queued work item, so it cannot cancel or flush it before tearing down the state that the worker uses. The buggy scenario involves two paths, with each

Bluetooth: 6lowpan: hold L2CAP conn across debugfs control

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: 6lowpan: hold L2CAP conn across debugfs control get_l2cap_conn() looks up an LE hci_conn under hdev protection, but then drops that protection before reading hcon->l2cap_data and before lowpan_control_write() later dereferences conn->hcon. A disconnect or device close can tear down the same L2CAP connection in that window. The buggy scenario involves two paths, with each column showing the order within that path: 6LoWPAN control write: HCI disconnect/device close: 1. get_l2cap_conn() finds hcon 1. hci_disconn_cfm() dispatches and hcon-

Bluetooth: MGMT: Fix adv monitor add failure cleanup

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix adv monitor add failure cleanup hci_add_adv_monitor() publishes a new adv_monitor in hdev->adv_monitors_idr before the powered MSFT setup step. The MSFT offload add path can then fail either locally before the controller add command completes, or in the MSFT add callback. In the current queued management add flow, hci_cmd_sync_work() still invokes mgmt_add_adv_patterns_monitor_complete() with the original pending command after msft_add_monitor_pattern() returns. The buggy scenario involves two paths, with each column showing the order within that path:

Bluetooth: L2CAP: fix tx ident leak for commands without a response

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix tx ident leak for commands without a response Commit 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident") changed ident allocation to use an IDA, releasing idents in l2cap_put_ident() when the matching response command is received. But identifiers allocated for commands that have no response defined are never released. In particular L2CAP_LE_CREDITS is sent repeatedly for the lifetime of an LE CoC channel, so a peer streaming data to the host exhausts the 1-255 ident range after 254 credit packets. From then on l2cap_get_ident() fa