user/sven/linux.git/include/uapi, branch v5.12.1

capabilities: require CAP_SETFCAP to map uid 0

2021-04-20T21:28:33Z

cap_setfcap is required to create file capabilities. Since commit 8db6c34f1dbc ("Introduce v3 namespaced file capabilities"), a process running as uid 0 but without cap_setfcap is able to work around this as follows: unshare a new user namespace which maps parent uid 0 into the child namespace. While this task will not have new capabilities against the parent namespace, there is a loophole due to the way namespaced file capabilities are represented as xattrs. File capabilities valid in userns 1 are distinguished from file capabilities valid in userns 2 by the kuid which underlies uid 0. Therefore the restricted root process can unshare a new self-mapping namespace, add a namespaced file capability onto a file, then use that file capability in the parent namespace. To prevent that, do not allow mapping parent uid 0 if the process which opened the uid_map file does not have CAP_SETFCAP, which is the capability for setting file capabilities. As a further wrinkle: a task can unshare its user namespace, then open its uid_map file itself, and map (only) its own uid. In this case we do not have the credential from before unshare, which was potentially more restricted. So, when creating a user namespace, we record whether the creator had CAP_SETFCAP. Then we can use that during map_write(). With this patch: 1. Unprivileged user can still unshare -Ur ubuntu@caps:~$ unshare -Ur root@caps:~# logout 2. Root user can still unshare -Ur ubuntu@caps:~$ sudo bash root@caps:/home/ubuntu# unshare -Ur root@caps:/home/ubuntu# logout 3. Root user without CAP_SETFCAP cannot unshare -Ur: root@caps:/home/ubuntu# /sbin/capsh --drop=cap_setfcap -- root@caps:/home/ubuntu# /sbin/setcap cap_setfcap=p /sbin/setcap unable to set CAP_SETFCAP effective capability: Operation not permitted root@caps:/home/ubuntu# unshare -Ur unshare: write failed /proc/self/uid_map: Operation not permitted Note: an alternative solution would be to allow uid 0 mappings by processes without CAP_SETFCAP, but to prevent such a namespace from writing any file capabilities. This approach can be seen at [1]. Background history: commit 95ebabde382 ("capabilities: Don't allow writing ambiguous v3 file capabilities") tried to fix the issue by preventing v3 fscaps to be written to disk when the root uid would map to the same uid in nested user namespaces. This led to regressions for various workloads. For example, see [2]. Ultimately this is a valid use-case we have to support meaning we had to revert this change in 3b0c2d3eaa83 ("Revert 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file capabilities")"). Link: https://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux.git/log/?h=2021-04-15/setfcap-nsfscaps-v4 [1] Link: https://github.com/containers/buildah/issues/3071 [2] Signed-off-by: Serge Hallyn Reviewed-by: Andrew G. Morgan Tested-by: Christian Brauner Reviewed-by: Christian Brauner Tested-by: Giuseppe Scrivano Cc: Eric Biederman Signed-off-by: Linus Torvalds

Merge tag 'dmaengine-fix-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

2021-04-14T16:36:54Z

Pull dmaengine fixes from Vinod Koul: "A couple of dmaengine driver fixes for: - race and descriptor issue for xilinx driver - fix interrupt handling, wq state & cleanup, field sizes for completion, msix permissions for idxd driver - runtime pm fix for tegra driver - double free fix in dma_async_device_register" * tag 'dmaengine-fix-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: dmaengine: idxd: fix wq cleanup of WQCFG registers dmaengine: idxd: clear MSIX permission entry on shutdown dmaengine: plx_dma: add a missing put_device() on error path dmaengine: tegra20: Fix runtime PM imbalance on error dmaengine: Fix a double free in dma_async_device_register dmaengine: dw: Make it dependent to HAS_IOMEM dmaengine: idxd: fix wq size store permission state dmaengine: idxd: fix opcap sysfs attribute output dmaengine: idxd: fix delta_rec and crc size field for completion record dmaengine: idxd: Fix clobbering of SWERR overflow bit on writeback dmaengine: xilinx: dpdma: Fix race condition in done IRQ dmaengine: xilinx: dpdma: Fix descriptor issuing on video group

dmaengine: idxd: fix delta_rec and crc size field for completion record

2021-04-12T07:56:03Z

The delta_rec_size and crc_val in the completion record should be 32bits and not 16bits. Fixes: bfe1d56091c1 ("dmaengine: idxd: Init and probe for Intel data accelerators") Reported-by: Nikhil Rao Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/161645618572.2003490.14466173451736323035.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

Merge tag 'net-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-04-09T22:26:51Z

Pull networking fixes from Jakub Kicinski: "Networking fixes for 5.12-rc7, including fixes from can, ipsec, mac80211, wireless, and bpf trees. No scary regressions here or in the works, but small fixes for 5.12 changes keep coming. Current release - regressions: - virtio: do not pull payload in skb->head - virtio: ensure mac header is set in virtio_net_hdr_to_skb() - Revert "net: correct sk_acceptq_is_full()" - mptcp: revert "mptcp: provide subflow aware release function" - ethernet: lan743x: fix ethernet frame cutoff issue - dsa: fix type was not set for devlink port - ethtool: remove link_mode param and derive link params from driver - sched: htb: fix null pointer dereference on a null new_q - wireless: iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_enqueue_hcmd() - wireless: iwlwifi: fw: fix notification wait locking - wireless: brcmfmac: p2p: Fix deadlock introduced by avoiding the rtnl dependency Current release - new code bugs: - napi: fix hangup on napi_disable for threaded napi - bpf: take module reference for trampoline in module - wireless: mt76: mt7921: fix airtime reporting and related tx hangs - wireless: iwlwifi: mvm: rfi: don't lock mvm->mutex when sending config command Previous releases - regressions: - rfkill: revert back to old userspace API by default - nfc: fix infinite loop, refcount & memory leaks in LLCP sockets - let skb_orphan_partial wake-up waiters - xfrm/compat: Cleanup WARN()s that can be user-triggered - vxlan, geneve: do not modify the shared tunnel info when PMTU triggers an ICMP reply - can: fix msg_namelen values depending on CAN_REQUIRED_SIZE - can: uapi: mark union inside struct can_frame packed - sched: cls: fix action overwrite reference counting - sched: cls: fix err handler in tcf_action_init() - ethernet: mlxsw: fix ECN marking in tunnel decapsulation - ethernet: nfp: Fix a use after free in nfp_bpf_ctrl_msg_rx - ethernet: i40e: fix receiving of single packets in xsk zero-copy mode - ethernet: cxgb4: avoid collecting SGE_QBASE regs during traffic Previous releases - always broken: - bpf: Refuse non-O_RDWR flags in BPF_OBJ_GET - bpf: Refcount task stack in bpf_get_task_stack - bpf, x86: Validate computation of branch displacements - ieee802154: fix many similar syzbot-found bugs - fix NULL dereferences in netlink attribute handling - reject unsupported operations on monitor interfaces - fix error handling in llsec_key_alloc() - xfrm: make ipv4 pmtu check honor ip header df - xfrm: make hash generation lock per network namespace - xfrm: esp: delete NETIF_F_SCTP_CRC bit from features for esp offload - ethtool: fix incorrect datatype in set_eee ops - xdp: fix xdp_return_frame() kernel BUG throw for page_pool memory model - openvswitch: fix send of uninitialized stack memory in ct limit reply Misc: - udp: add get handling for UDP_GRO sockopt" * tag 'net-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (182 commits) net: fix hangup on napi_disable for threaded napi net: hns3: Trivial spell fix in hns3 driver lan743x: fix ethernet frame cutoff issue net: ipv6: check for validity before dereferencing cfg->fc_nlinfo.nlh net: dsa: lantiq_gswip: Configure all remaining GSWIP_MII_CFG bits net: dsa: lantiq_gswip: Don't use PHY auto polling net: sched: sch_teql: fix null-pointer dereference ipv6: report errors for iftoken via netlink extack net: sched: fix err handler in tcf_action_init() net: sched: fix action overwrite reference counting Revert "net: sched: bump refcount for new action in ACT replace mode" ice: fix memory leak of aRFS after resuming from suspend i40e: Fix sparse warning: missing error code 'err' i40e: Fix sparse error: 'vsi->netdev' could be null i40e: Fix sparse error: uninitialized symbol 'ring' i40e: Fix sparse errors in i40e_txrx.c i40e: Fix parameters in aq_get_phy_register() nl80211: fix beacon head validation bpf, x86: Validate computation of branch displacements for x86-32 bpf, x86: Validate computation of branch displacements for x86-64 ...

rfkill: revert back to old userspace API by default

2021-04-08T08:14:45Z

Recompiling with the new extended version of struct rfkill_event broke systemd in *two* ways: - It used "sizeof(struct rfkill_event)" to read the event, but then complained if it actually got something != 8, this broke it on new kernels (that include the updated API); - It used sizeof(struct rfkill_event) to write a command, but didn't implement the intended expansion protocol where the kernel returns only how many bytes it accepted, and errored out due to the unexpected smaller size on kernels that didn't include the updated API. Even though systemd has now been fixed, that fix may not be always deployed, and other applications could potentially have similar issues. As such, in the interest of avoiding regressions, revert the default API "struct rfkill_event" back to the original size. Instead, add a new "struct rfkill_event_ext" that extends it by the new field, and even more clearly document that applications should be prepared for extensions in two ways: * write might only accept fewer bytes on older kernels, and will return how many to let userspace know which data may have been ignored; * read might return anything between 8 (the original size) and whatever size the application sized its buffer at, indicating how much event data was supported by the kernel. Perhaps that will help avoid such issues in the future and we won't have to come up with another version of the struct if we ever need to extend it again. Applications that want to take advantage of the new field will have to be modified to use struct rfkill_event_ext instead now, which comes with the danger of them having already been updated to use it from 'struct rfkill_event', but I found no evidence of that, and it's still relatively new. Cc: stable@vger.kernel.org # 5.11 Reported-by: Takashi Iwai Tested-by: Sedat Dilek # LLVM/Clang v12.0.0-r4 (x86-64) Link: https://lore.kernel.org/r/20210319232510.f1a139cfdd9c.Ic5c7c9d1d28972059e132ea653a21a427c326678@changeid Signed-off-by: Johannes Berg

ethtool: fix kdoc in headers

2021-04-07T21:22:49Z

Fix remaining issues with kdoc in the ethtool headers. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: document reserved fields in the uAPI

2021-04-07T21:22:49Z

Add a note on expected handling of reserved fields, and references to all kdocs. This fixes a bunch of kdoc warnings. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: un-kdocify extended link state

2021-04-07T21:22:49Z

Extended link state structures and enums use kdoc headers but then do not describe any of the members. Convert to normal comments. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

Merge tag 'block-5.12-2021-04-02' of git://git.kernel.dk/linux-block

2021-04-02T23:13:13Z

Pull block fixes from Jens Axboe: - Remove comment that never came to fruition in 22 years of development (Christoph) - Remove unused request flag (Christoph) - Fix for null_blk fake timeout handling (Damien) - Fix for IOCB_NOWAIT being ignored for O_DIRECT on raw bdevs (Pavel) - Error propagation fix for multiple split bios (Yufen) * tag 'block-5.12-2021-04-02' of git://git.kernel.dk/linux-block: block: remove the unused RQF_ALLOCED flag block: update a few comments in uapi/linux/blkpg.h block: don't ignore REQ_NOWAIT for direct IO null_blk: fix command timeout completion handling block: only update parent bi_status when bio fail

block: update a few comments in uapi/linux/blkpg.h

2021-04-02T17:18:30Z

The big top of the file comment talk about grand plans that never happened, so remove them to not confuse the readers. Also mark the devname and volname fields as ignored as they were never used by the kernel. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe