linux-rng/net/core, branch master

Merge tag 'core-uaccess-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T16:01:39Z

Pull scoped user access updates from Thomas Gleixner: "Scoped user mode access and related changes: - Implement the missing u64 user access function on ARM when CONFIG_CPU_SPECTRE=n. This makes it possible to access a 64bit value in generic code with [unsafe_]get_user(). All other architectures and ARM variants provide the relevant accessors already. - Ensure that ASM GOTO jump label usage in the user mode access helpers always goes through a local C scope label indirection inside the helpers. This is required because compilers are not supporting that a ASM GOTO target leaves a auto cleanup scope. GCC silently fails to emit the cleanup invocation and CLANG fails the build. [ Editor's note: gcc-16 will have fixed the code generation issue in commit f68fe3ddda4 ("eh: Invoke cleanups/destructors in asm goto jumps [PR122835]"). But we obviously have to deal with clang and older versions of gcc, so.. - Linus ] This provides generic wrapper macros and the conversion of affected architecture code to use them. - Scoped user mode access with auto cleanup Access to user mode memory can be required in hot code paths, but if it has to be done with user controlled pointers, the access is shielded with a speculation barrier, so that the CPU cannot speculate around the address range check. Those speculation barriers impact performance quite significantly. This cost can be avoided by "masking" the provided pointer so it is guaranteed to be in the valid user memory access range and otherwise to point to a guaranteed unpopulated address space. This has to be done without branches so it creates an address dependency for the access, which the CPU cannot speculate ahead. This results in repeating and error prone programming patterns: if (can_do_masked_user_access()) from = masked_user_read_access_begin((from)); else if (!user_read_access_begin(from, sizeof(*from))) return -EFAULT; unsafe_get_user(val, from, Efault); user_read_access_end(); return 0; Efault: user_read_access_end(); return -EFAULT; which can be replaced with scopes and automatic cleanup: scoped_user_read_access(from, Efault) unsafe_get_user(val, from, Efault); return 0; Efault: return -EFAULT; - Convert code which implements the above pattern over to scope_user.*.access(). This also corrects a couple of imbalanced masked_*_begin() instances which are harmless on most architectures, but prevent PowerPC from implementing the masking optimization. - Add a missing speculation barrier in copy_from_user_iter()" * tag 'core-uaccess-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lib/strn*,uaccess: Use masked_user_{read/write}_access_begin when required scm: Convert put_cmsg() to scoped user access iov_iter: Add missing speculation barrier to copy_from_user_iter() iov_iter: Convert copy_from_user_iter() to masked user access select: Convert to scoped user access x86/futex: Convert to scoped user access futex: Convert to get/put_user_inline() uaccess: Provide put/get_user_inline() uaccess: Provide scoped user access regions arm64: uaccess: Use unsafe wrappers for ASM GOTO s390/uaccess: Use unsafe wrappers for ASM GOTO riscv/uaccess: Use unsafe wrappers for ASM GOTO powerpc/uaccess: Use unsafe wrappers for ASM GOTO x86/uaccess: Use unsafe wrappers for ASM GOTO uaccess: Provide ASM GOTO safe wrappers for unsafe_*_user() ARM: uaccess: Implement missing __get_user_asm_dword()

Merge tag 'namespace-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-01T17:47:41Z

Pull namespace updates from Christian Brauner: "This contains substantial namespace infrastructure changes including a new system call, active reference counting, and extensive header cleanups. The branch depends on the shared kbuild branch for -fms-extensions support. Features: - listns() system call Add a new listns() system call that allows userspace to iterate through namespaces in the system. This provides a programmatic interface to discover and inspect namespaces, addressing longstanding limitations: Currently, there is no direct way for userspace to enumerate namespaces. Applications must resort to scanning /proc/*/ns/ across all processes, which is: - Inefficient - requires iterating over all processes - Incomplete - misses namespaces not attached to any running process but kept alive by file descriptors, bind mounts, or parent references - Permission-heavy - requires access to /proc for many processes - No ordering or ownership information - No filtering per namespace type The listns() system call solves these problems: ssize_t listns(const struct ns_id_req *req, u64 *ns_ids, size_t nr_ns_ids, unsigned int flags); struct ns_id_req { __u32 size; __u32 spare; __u64 ns_id; struct /* listns */ { __u32 ns_type; __u32 spare2; __u64 user_ns_id; }; }; Features include: - Pagination support for large namespace sets - Filtering by namespace type (MNT_NS, NET_NS, USER_NS, etc.) - Filtering by owning user namespace - Permission checks respecting namespace isolation - Active Reference Counting Introduce an active reference count that tracks namespace visibility to userspace. A namespace is visible in the following cases: - The namespace is in use by a task - The namespace is persisted through a VFS object (namespace file descriptor or bind-mount) - The namespace is a hierarchical type and is the parent of child namespaces The active reference count does not regulate lifetime (that's still done by the normal reference count) - it only regulates visibility to namespace file handles and listns(). This prevents resurrection of namespaces that are pinned only for internal kernel reasons (e.g., user namespaces held by file->f_cred, lazy TLB references on idle CPUs, etc.) which should not be accessible via (1)-(3). - Unified Namespace Tree Introduce a unified tree structure for all namespaces with: - Fixed IDs assigned to initial namespaces - Lookup based solely on inode number - Maintained list of owned namespaces per user namespace - Simplified rbtree comparison helpers Cleanups - Header Reorganization: - Move namespace types into separate header (ns_common_types.h) - Decouple nstree from ns_common header - Move nstree types into separate header - Switch to new ns_tree_{node,root} structures with helper functions - Use guards for ns_tree_lock - Initial Namespace Reference Count Optimization - Make all reference counts on initial namespaces a nop to avoid pointless cacheline ping-pong for namespaces that can never go away - Drop custom reference count initialization for initial namespaces - Add NS_COMMON_INIT() macro and use it for all namespaces - pid: rely on common reference count behavior - Miscellaneous Cleanups - Rename exit_task_namespaces() to exit_nsproxy_namespaces() - Rename is_initial_namespace() and make argument const - Use boolean to indicate anonymous mount namespace - Simplify owner list iteration in nstree - nsfs: raise SB_I_NODEV, SB_I_NOEXEC, and DCACHE_DONTCACHE explicitly - nsfs: use inode_just_drop() - pidfs: raise DCACHE_DONTCACHE explicitly - pidfs: simplify PIDFD_GET__NAMESPACE ioctls - libfs: allow to specify s_d_flags - cgroup: add cgroup namespace to tree after owner is set - nsproxy: fix free_nsproxy() and simplify create_new_namespaces() Fixes: - setns(pidfd, ...) race condition Fix a subtle race when using pidfds with setns(). When the target task exits after prepare_nsset() but before commit_nsset(), the namespace's active reference count might have been dropped. If setns() then installs the namespaces, it would bump the active reference count from zero without taking the required reference on the owner namespace, leading to underflow when later decremented. The fix resurrects the ownership chain if necessary - if the caller succeeded in grabbing passive references, the setns() should succeed even if the target task exits or gets reaped. - Return EFAULT on put_user() error instead of success - Make sure references are dropped outside of RCU lock (some namespaces like mount namespace sleep when putting the last reference) - Don't skip active reference count initialization for network namespace - Add asserts for active refcount underflow - Add asserts for initial namespace reference counts (both passive and active) - ipc: enable is_ns_init_id() assertions - Fix kernel-doc comments for internal nstree functions - Selftests - 15 active reference count tests - 9 listns() functionality tests - 7 listns() permission tests - 12 inactive namespace resurrection tests - 3 threaded active reference count tests - commit_creds() active reference tests - Pagination and stress tests - EFAULT handling test - nsid tests fixes" * tag 'namespace-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (103 commits) pidfs: simplify PIDFD_GET__NAMESPACE ioctls nstree: fix kernel-doc comments for internal functions nsproxy: fix free_nsproxy() and simplify create_new_namespaces() selftests/namespaces: fix nsid tests ns: drop custom reference count initialization for initial namespaces pid: rely on common reference count behavior ns: add asserts for initial namespace active reference counts ns: add asserts for initial namespace reference counts ns: make all reference counts on initial namespace a nop ipc: enable is_ns_init_id() assertions fs: use boolean to indicate anonymous mount namespace ns: rename is_initial_namespace() ns: make is_initial_namespace() argument const nstree: use guards for ns_tree_lock nstree: simplify owner list iteration nstree: switch to new structures nstree: add helper to operate on struct ns_tree_{node,root} nstree: move nstree types into separate header nstree: decouple from ns_common header ns: move namespace types into separate header ...

scm: Convert put_cmsg() to scoped user access

2025-11-18T14:27:34Z

Replace the open coded implementation with the scoped user access guard. That also corrects the imbalance between masked_user_access_begin() and user_write_access_end(), which would affect PowerPC when it gains masked user access support. No functional change intended. [ tglx: Amend change log ] Signed-off-by: Christophe Leroy Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/793219313f641eda09a892d06768d2837246bf9f.1763396724.git.christophe.leroy@csgroup.eu

net: core: prevent NULL deref in generic_hwtstamp_ioctl_lower()

2025-11-14T01:23:21Z

The ethtool tsconfig Netlink path can trigger a null pointer dereference. A call chain such as: tsconfig_prepare_data() -> dev_get_hwtstamp_phylib() -> vlan_hwtstamp_get() -> generic_hwtstamp_get_lower() -> generic_hwtstamp_ioctl_lower() results in generic_hwtstamp_ioctl_lower() being called with kernel_cfg->ifr as NULL. The generic_hwtstamp_ioctl_lower() function does not expect a NULL ifr and dereferences it, leading to a system crash. Fix this by adding a NULL check for kernel_cfg->ifr in generic_hwtstamp_ioctl_lower(). If ifr is NULL, return -EINVAL. Fixes: 6e9e2eed4f39 ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config") Closes: https://lore.kernel.org/cd6a7056-fa6d-43f8-b78a-f5e811247ba8@linux.dev Signed-off-by: Jiaming Zhang Reviewed-by: Kory Maincent Link: https://patch.msgid.link/20251111173652.749159-2-r772577952@gmail.com Signed-off-by: Jakub Kicinski

Merge branch 'kbuild-6.19.fms.extension'

2025-11-11T08:59:08Z

Bring in the shared branch with the kbuild tree to enable '-fms-extensions' for 6.19. Further namespace cleanup work requires this extension. Signed-off-by: Christian Brauner

net: netpoll: fix incorrect refcount handling causing incorrect cleanup

2025-11-11T02:34:44Z

commit efa95b01da18 ("netpoll: fix use after free") incorrectly ignored the refcount and prematurely set dev->npinfo to NULL during netpoll cleanup, leading to improper behavior and memory leaks. Scenario causing lack of proper cleanup: 1) A netpoll is associated with a NIC (e.g., eth0) and netdev->npinfo is allocated, and refcnt = 1 - Keep in mind that npinfo is shared among all netpoll instances. In this case, there is just one. 2) Another netpoll is also associated with the same NIC and npinfo->refcnt += 1. - Now dev->npinfo->refcnt = 2; - There is just one npinfo associated to the netdev. 3) When the first netpolls goes to clean up: - The first cleanup succeeds and clears np->dev->npinfo, ignoring refcnt. - It basically calls `RCU_INIT_POINTER(np->dev->npinfo, NULL);` - Set dev->npinfo = NULL, without proper cleanup - No ->ndo_netpoll_cleanup() is either called 4) Now the second target tries to clean up - The second cleanup fails because np->dev->npinfo is already NULL. * In this case, ops->ndo_netpoll_cleanup() was never called, and the skb pool is not cleaned as well (for the second netpoll instance) - This leaks npinfo and skbpool skbs, which is clearly reported by kmemleak. Revert commit efa95b01da18 ("netpoll: fix use after free") and adds clarifying comments emphasizing that npinfo cleanup should only happen once the refcount reaches zero, ensuring stable and correct netpoll behavior. Cc: # 3.17.x Cc: Jay Vosburgh Fixes: efa95b01da18 ("netpoll: fix use after free") Signed-off-by: Breno Leitao Reviewed-by: Simon Horman Link: https://patch.msgid.link/20251107-netconsole_torture-v10-1-749227b55f63@debian.org Signed-off-by: Jakub Kicinski

Merge tag 'net-6.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-11-06T16:52:30Z

Pull networking fixes from Jakub Kicinski: Including fixes from bluetooth and wireless. Current release - new code bugs: - ptp: expose raw cycles only for clocks with free-running counter - bonding: fix null-deref in actor_port_prio setting - mdio: ERR_PTR-check regmap pointer returned by device_node_to_regmap() - eth: libie: depend on DEBUG_FS when building LIBIE_FWLOG Previous releases - regressions: - virtio_net: fix perf regression due to bad alignment of virtio_net_hdr_v1_hash - Revert "wifi: ath10k: avoid unnecessary wait for service ready message" caused regressions for QCA988x and QCA9984 - Revert "wifi: ath12k: Fix missing station power save configuration" caused regressions for WCN7850 - eth: bnxt_en: shutdown FW DMA in bnxt_shutdown(), fix memory corruptions after kexec Previous releases - always broken: - virtio-net: fix received packet length check for big packets - sctp: fix races in socket diag handling - wifi: add an hrtimer-based delayed work item to avoid low granularity of timers set relatively far in the future, and use it where it matters (e.g. when performing AP-scheduled channel switch) - eth: mlx5e: - correctly propagate error in case of module EEPROM read failure - fix HW-GRO on systems with PAGE_SIZE == 64kB - dsa: b53: fixes for tagging, link configuration / RMII, FDB, multicast - phy: lan8842: implement latest errata" * tag 'net-6.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (63 commits) selftests/vsock: avoid false-positives when checking dmesg net: bridge: fix MST static key usage net: bridge: fix use-after-free due to MST port state bypass lan966x: Fix sleeping in atomic context bonding: fix NULL pointer dereference in actor_port_prio setting net: dsa: microchip: Fix reserved multicast address table programming net: wan: framer: pef2256: Switch to devm_mfd_add_devices() net: libwx: fix device bus LAN ID net/mlx5e: SHAMPO, Fix header formulas for higher MTUs and 64K pages net/mlx5e: SHAMPO, Fix skb size check for 64K pages net/mlx5e: SHAMPO, Fix header mapping for 64K pages net: ti: icssg-prueth: Fix fdb hash size configuration net/mlx5e: Fix return value in case of module EEPROM read error net: gro_cells: Reduce lock scope in gro_cell_poll libie: depend on DEBUG_FS when building LIBIE_FWLOG wifi: mac80211_hwsim: Limit destroy_on_close radio removal to netgroup netpoll: Fix deadlock in memory allocation under spinlock net: ethernet: ti: netcp: Standardize knav_dma_open_channel to return NULL on error virtio-net: fix received length check in big packets bnxt_en: Fix warning in bnxt_dl_reload_down() ...

net: gro_cells: Reduce lock scope in gro_cell_poll

2025-11-06T01:41:29Z

One GRO-cell device's NAPI callback can nest into the GRO-cell of another device if the underlying device is also using GRO-cell. This is the case for IPsec over vxlan. These two GRO-cells are separate devices. From lockdep's point of view it is the same because each device is sharing the same lock class and so it reports a possible deadlock assuming one device is nesting into itself. Hold the bh_lock only while accessing gro_cell::napi_skbs in gro_cell_poll(). This reduces the locking scope and avoids acquiring the same lock class multiple times. Fixes: 25718fdcbdd2 ("net: gro_cells: Use nested-BH locking for gro_cell") Reported-by: Gal Pressman Closes: https://lore.kernel.org/all/66664116-edb8-48dc-ad72-d5223696dd19@nvidia.com/ Signed-off-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20251104153435.ty88xDQt@linutronix.de Signed-off-by: Jakub Kicinski

netpoll: Fix deadlock in memory allocation under spinlock

2025-11-05T03:17:00Z

Fix a AA deadlock in refill_skbs() where memory allocation while holding skb_pool->lock can trigger a recursive lock acquisition attempt. The deadlock scenario occurs when the system is under severe memory pressure: 1. refill_skbs() acquires skb_pool->lock (spinlock) 2. alloc_skb() is called while holding the lock 3. Memory allocator fails and calls slab_out_of_memory() 4. This triggers printk() for the OOM warning 5. The console output path calls netpoll_send_udp() 6. netpoll_send_udp() attempts to acquire the same skb_pool->lock 7. Deadlock: the lock is already held by the same CPU Call stack: refill_skbs() spin_lock_irqsave(&skb_pool->lock) <- lock acquired __alloc_skb() kmem_cache_alloc_node_noprof() slab_out_of_memory() printk() console_flush_all() netpoll_send_udp() skb_dequeue() spin_lock_irqsave(&skb_pool->lock) <- deadlock attempt This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb refilling on critical path") which removed refill_skbs() from the critical path (where nested printk was being deferred), letting nested printk being called from inside refill_skbs() Refactor refill_skbs() to never allocate memory while holding the spinlock. Another possible solution to fix this problem is protecting the refill_skbs() from nested printks, basically calling printk_deferred_{enter,exit}() in refill_skbs(), then, any nested pr_warn() would be deferred. I prefer this approach, given I _think_ it might be a good idea to move the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having the alloc_skb() outside of the lock will be necessary step. There is a possible TOCTOU issue when checking for the pool length, and queueing the new allocated skb, but, this is not an issue, given that an extra SKB in the pool is harmless and it will be eventually used. Signed-off-by: Breno Leitao Fixes: 248f6571fd4c51 ("netpoll: Optimize skb refilling on critical path") Reviewed-by: Simon Horman Link: https://patch.msgid.link/20251103-fix_netpoll_aa-v4-1-4cfecdf6da7c@debian.org Signed-off-by: Jakub Kicinski

nstree: assign fixed ids to the initial namespaces

2025-11-03T16:41:17Z

The initial set of namespace comes with fixed inode numbers making it easy for userspace to identify them solely based on that information. This has long preceeded anything here. Similarly, let's assign fixed namespace ids for the initial namespaces. Kill the cookie and use a sequentially increasing number. This has the nice side-effect that the owning user namespace will always have a namespace id that is smaller than any of it's descendant namespaces. Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-15-2e6f823ebdc0@kernel.org Signed-off-by: Christian Brauner