Commit Graph

293 Commits

Author SHA1 Message Date
Magnus Karlsson
85c2c79a07 xsk: fix refcount underflow in error path
Fix a refcount underflow problem reported by syzbot that can happen
when a system is running out of memory. If xp_alloc_tx_descs() fails,
and it can only fail due to not having enough memory, then the error
path is triggered. In this error path, the refcount of the pool is
decremented as it has incremented before. However, the reference to
the pool in the socket was not nulled. This means that when the socket
is closed later, the socket teardown logic will think that there is a
pool attached to the socket and try to decrease the refcount again,
leading to a refcount underflow.

I chose this fix as it involved adding just a single line. Another
option would have been to move xp_get_pool() and the assignment of
xs->pool to after the if-statement and using xs_umem->pool instead of
xs->pool in the whole if-statement resulting in somewhat simpler code,
but this would have led to much more churn in the code base perhaps
making it harder to backport.

Fixes: ba3beec2ec ("xsk: Fix possible crash when multiple sockets are created")
Reported-by: syzbot+8ada0057e69293a05fd4@syzkaller.appspotmail.com
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230809142843.13944-1-magnus.karlsson@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-09 20:08:04 -07:00
Eric Dumazet
3c5b4d69c3 net: annotate data-races around sk->sk_mark
sk->sk_mark is often read while another thread could change the value.

Fixes: 4a19ec5800 ("[NET]: Introducing socket mark socket option.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-29 18:13:41 +01:00
Ilya Maximets
f7306acec9 xsk: Honor SO_BINDTODEVICE on bind
Initial creation of an AF_XDP socket requires CAP_NET_RAW capability. A
privileged process might create the socket and pass it to a non-privileged
process for later use. However, that process will be able to bind the socket
to any network interface. Even though it will not be able to receive any
traffic without modification of the BPF map, the situation is not ideal.

Sockets already have a mechanism that can be used to restrict what interface
they can be attached to. That is SO_BINDTODEVICE.

To change the SO_BINDTODEVICE binding the process will need CAP_NET_RAW.

Make xsk_bind() honor the SO_BINDTODEVICE in order to allow safer workflow
when non-privileged process is using AF_XDP.

The intended workflow is following:

  1. First process creates a bare socket with socket(AF_XDP, ...).
  2. First process loads the XSK program to the interface.
  3. First process adds the socket fd to a BPF map.
  4. First process ties socket fd to a particular interface using
     SO_BINDTODEVICE.
  5. First process sends socket fd to a second process.
  6. Second process allocates UMEM.
  7. Second process binds socket to the interface with bind(...).
  8. Second process sends/receives the traffic.

All the steps above are possible today if the first process is privileged
and the second one has sufficient RLIMIT_MEMLOCK and no capabilities.
However, the second process will be able to bind the socket to any interface
it wants on step 7 and send traffic from it. With the proposed change, the
second process will be able to bind the socket only to a specific interface
chosen by the first process at step 4.

Fixes: 965a990984 ("xsk: add support for bind for Rx")
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/bpf/20230703175329.3259672-1-i.maximets@ovn.org
2023-07-04 10:19:48 +02:00
Linus Torvalds
3a8a670eee Networking changes for 6.5.
Core
 ----
 
  - Rework the sendpage & splice implementations. Instead of feeding
    data into sockets page by page extend sendmsg handlers to support
    taking a reference on the data, controlled by a new flag called
    MSG_SPLICE_PAGES. Rework the handling of unexpected-end-of-file
    to invoke an additional callback instead of trying to predict what
    the right combination of MORE/NOTLAST flags is.
    Remove the MSG_SENDPAGE_NOTLAST flag completely.
 
  - Implement SCM_PIDFD, a new type of CMSG type analogous to
    SCM_CREDENTIALS, but it contains pidfd instead of plain pid.
 
  - Enable socket busy polling with CONFIG_RT.
 
  - Improve reliability and efficiency of reporting for ref_tracker.
 
  - Auto-generate a user space C library for various Netlink families.
 
 Protocols
 ---------
 
  - Allow TCP to shrink the advertised window when necessary, prevent
    sk_rcvbuf auto-tuning from growing the window all the way up to
    tcp_rmem[2].
 
  - Use per-VMA locking for "page-flipping" TCP receive zerocopy.
 
  - Prepare TCP for device-to-device data transfers, by making sure
    that payloads are always attached to skbs as page frags.
 
  - Make the backoff time for the first N TCP SYN retransmissions
    linear. Exponential backoff is unnecessarily conservative.
 
  - Create a new MPTCP getsockopt to retrieve all info (MPTCP_FULL_INFO).
 
  - Avoid waking up applications using TLS sockets until we have
    a full record.
 
  - Allow using kernel memory for protocol ioctl callbacks, paving
    the way to issuing ioctls over io_uring.
 
  - Add nolocalbypass option to VxLAN, forcing packets to be fully
    encapsulated even if they are destined for a local IP address.
 
  - Make TCPv4 use consistent hash in TIME_WAIT and SYN_RECV. Ensure
    in-kernel ECMP implementation (e.g. Open vSwitch) select the same
    link for all packets. Support L4 symmetric hashing in Open vSwitch.
 
  - PPPoE: make number of hash bits configurable.
 
  - Allow DNS to be overwritten by DHCPACK in the in-kernel DHCP client
    (ipconfig).
 
  - Add layer 2 miss indication and filtering, allowing higher layers
    (e.g. ACL filters) to make forwarding decisions based on whether
    packet matched forwarding state in lower devices (bridge).
 
  - Support matching on Connectivity Fault Management (CFM) packets.
 
  - Hide the "link becomes ready" IPv6 messages by demoting their
    printk level to debug.
 
  - HSR: don't enable promiscuous mode if device offloads the proto.
 
  - Support active scanning in IEEE 802.15.4.
 
  - Continue work on Multi-Link Operation for WiFi 7.
 
 BPF
 ---
 
  - Add precision propagation for subprogs and callbacks. This allows
    maintaining verification efficiency when subprograms are used,
    or in fact passing the verifier at all for complex programs,
    especially those using open-coded iterators.
 
  - Improve BPF's {g,s}setsockopt() length handling. Previously BPF
    assumed the length is always equal to the amount of written data.
    But some protos allow passing a NULL buffer to discover what
    the output buffer *should* be, without writing anything.
 
  - Accept dynptr memory as memory arguments passed to helpers.
 
  - Add routing table ID to bpf_fib_lookup BPF helper.
 
  - Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands.
 
  - Drop bpf_capable() check in BPF_MAP_FREEZE command (used to mark
    maps as read-only).
 
  - Show target_{obj,btf}_id in tracing link fdinfo.
 
  - Addition of several new kfuncs (most of the names are self-explanatory):
    - Add a set of new dynptr kfuncs: bpf_dynptr_adjust(),
      bpf_dynptr_is_null(), bpf_dynptr_is_rdonly(), bpf_dynptr_size()
      and bpf_dynptr_clone().
    - bpf_task_under_cgroup()
    - bpf_sock_destroy() - force closing sockets
    - bpf_cpumask_first_and(), rework bpf_cpumask_any*() kfuncs
 
 Netfilter
 ---------
 
  - Relax set/map validation checks in nf_tables. Allow checking
    presence of an entry in a map without using the value.
 
  - Increase ip_vs_conn_tab_bits range for 64BIT builds.
 
  - Allow updating size of a set.
 
  - Improve NAT tuple selection when connection is closing.
 
 Driver API
 ----------
 
  - Integrate netdev with LED subsystem, to allow configuring HW
    "offloaded" blinking of LEDs based on link state and activity
    (i.e. packets coming in and out).
 
  - Support configuring rate selection pins of SFP modules.
 
  - Factor Clause 73 auto-negotiation code out of the drivers, provide
    common helper routines.
 
  - Add more fool-proof helpers for managing lifetime of MDIO devices
    associated with the PCS layer.
 
  - Allow drivers to report advanced statistics related to Time Aware
    scheduler offload (taprio).
 
  - Allow opting out of VF statistics in link dump, to allow more VFs
    to fit into the message.
 
  - Split devlink instance and devlink port operations.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Synopsys EMAC4 IP support (stmmac)
    - Marvell 88E6361 8 port (5x1GE + 3x2.5GE) switches
    - Marvell 88E6250 7 port switches
    - Microchip LAN8650/1 Rev.B0 PHYs
    - MediaTek MT7981/MT7988 built-in 1GE PHY driver
 
  - WiFi:
    - Realtek RTL8192FU, 2.4 GHz, b/g/n mode, 2T2R, 300 Mbps
    - Realtek RTL8723DS (SDIO variant)
    - Realtek RTL8851BE
 
  - CAN:
    - Fintek F81604
 
 Drivers
 -------
 
  - Ethernet NICs:
    - Intel (100G, ice):
      - support dynamic interrupt allocation
      - use meta data match instead of VF MAC addr on slow-path
    - nVidia/Mellanox:
      - extend link aggregation to handle 4, rather than just 2 ports
      - spawn sub-functions without any features by default
    - OcteonTX2:
      - support HTB (Tx scheduling/QoS) offload
      - make RSS hash generation configurable
      - support selecting Rx queue using TC filters
    - Wangxun (ngbe/txgbe):
      - add basic Tx/Rx packet offloads
      - add phylink support (SFP/PCS control)
    - Freescale/NXP (enetc):
      - report TAPRIO packet statistics
    - Solarflare/AMD:
      - support matching on IP ToS and UDP source port of outer header
      - VxLAN and GENEVE tunnel encapsulation over IPv4 or IPv6
      - add devlink dev info support for EF10
 
  - Virtual NICs:
    - Microsoft vNIC:
      - size the Rx indirection table based on requested configuration
      - support VLAN tagging
    - Amazon vNIC:
      - try to reuse Rx buffers if not fully consumed, useful for ARM
        servers running with 16kB pages
    - Google vNIC:
      - support TCP segmentation of >64kB frames
 
  - Ethernet embedded switches:
    - Marvell (mv88e6xxx):
      - enable USXGMII (88E6191X)
    - Microchip:
     - lan966x: add support for Egress Stage 0 ACL engine
     - lan966x: support mapping packet priority to internal switch
       priority (based on PCP or DSCP)
 
  - Ethernet PHYs:
    - Broadcom PHYs:
      - support for Wake-on-LAN for BCM54210E/B50212E
      - report LPI counter
    - Microsemi PHYs: support RGMII delay configuration (VSC85xx)
    - Micrel PHYs: receive timestamp in the frame (LAN8841)
    - Realtek PHYs: support optional external PHY clock
    - Altera TSE PCS: merge the driver into Lynx PCS which it is
      a variant of
 
  - CAN: Kvaser PCIEcan:
    - support packet timestamping
 
  - WiFi:
    - Intel (iwlwifi):
      - major update for new firmware and Multi-Link Operation (MLO)
      - configuration rework to drop test devices and split
        the different families
      - support for segmented PNVM images and power tables
      - new vendor entries for PPAG (platform antenna gain) feature
    - Qualcomm 802.11ax (ath11k):
      - Multiple Basic Service Set Identifier (MBSSID) and
        Enhanced MBSSID Advertisement (EMA) support in AP mode
      - support factory test mode
    - RealTek (rtw89):
      - add RSSI based antenna diversity
      - support U-NII-4 channels on 5 GHz band
    - RealTek (rtl8xxxu):
      - AP mode support for 8188f
      - support USB RX aggregation for the newer chips
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking changes from Jakub Kicinski:
 "WiFi 7 and sendpage changes are the biggest pieces of work for this
  release. The latter will definitely require fixes but I think that we
  got it to a reasonable point.

  Core:

   - Rework the sendpage & splice implementations

     Instead of feeding data into sockets page by page extend sendmsg
     handlers to support taking a reference on the data, controlled by a
     new flag called MSG_SPLICE_PAGES

     Rework the handling of unexpected-end-of-file to invoke an
     additional callback instead of trying to predict what the right
     combination of MORE/NOTLAST flags is

     Remove the MSG_SENDPAGE_NOTLAST flag completely

   - Implement SCM_PIDFD, a new type of CMSG type analogous to
     SCM_CREDENTIALS, but it contains pidfd instead of plain pid

   - Enable socket busy polling with CONFIG_RT

   - Improve reliability and efficiency of reporting for ref_tracker

   - Auto-generate a user space C library for various Netlink families

  Protocols:

   - Allow TCP to shrink the advertised window when necessary, prevent
     sk_rcvbuf auto-tuning from growing the window all the way up to
     tcp_rmem[2]

   - Use per-VMA locking for "page-flipping" TCP receive zerocopy

   - Prepare TCP for device-to-device data transfers, by making sure
     that payloads are always attached to skbs as page frags

   - Make the backoff time for the first N TCP SYN retransmissions
     linear. Exponential backoff is unnecessarily conservative

   - Create a new MPTCP getsockopt to retrieve all info
     (MPTCP_FULL_INFO)

   - Avoid waking up applications using TLS sockets until we have a full
     record

   - Allow using kernel memory for protocol ioctl callbacks, paving the
     way to issuing ioctls over io_uring

   - Add nolocalbypass option to VxLAN, forcing packets to be fully
     encapsulated even if they are destined for a local IP address

   - Make TCPv4 use consistent hash in TIME_WAIT and SYN_RECV. Ensure
     in-kernel ECMP implementation (e.g. Open vSwitch) select the same
     link for all packets. Support L4 symmetric hashing in Open vSwitch

   - PPPoE: make number of hash bits configurable

   - Allow DNS to be overwritten by DHCPACK in the in-kernel DHCP client
     (ipconfig)

   - Add layer 2 miss indication and filtering, allowing higher layers
     (e.g. ACL filters) to make forwarding decisions based on whether
     packet matched forwarding state in lower devices (bridge)

   - Support matching on Connectivity Fault Management (CFM) packets

   - Hide the "link becomes ready" IPv6 messages by demoting their
     printk level to debug

   - HSR: don't enable promiscuous mode if device offloads the proto

   - Support active scanning in IEEE 802.15.4

   - Continue work on Multi-Link Operation for WiFi 7

  BPF:

   - Add precision propagation for subprogs and callbacks. This allows
     maintaining verification efficiency when subprograms are used, or
     in fact passing the verifier at all for complex programs,
     especially those using open-coded iterators

   - Improve BPF's {g,s}setsockopt() length handling. Previously BPF
     assumed the length is always equal to the amount of written data.
     But some protos allow passing a NULL buffer to discover what the
     output buffer *should* be, without writing anything

   - Accept dynptr memory as memory arguments passed to helpers

   - Add routing table ID to bpf_fib_lookup BPF helper

   - Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands

   - Drop bpf_capable() check in BPF_MAP_FREEZE command (used to mark
     maps as read-only)

   - Show target_{obj,btf}_id in tracing link fdinfo

   - Addition of several new kfuncs (most of the names are
     self-explanatory):
      - Add a set of new dynptr kfuncs: bpf_dynptr_adjust(),
        bpf_dynptr_is_null(), bpf_dynptr_is_rdonly(), bpf_dynptr_size()
        and bpf_dynptr_clone().
      - bpf_task_under_cgroup()
      - bpf_sock_destroy() - force closing sockets
      - bpf_cpumask_first_and(), rework bpf_cpumask_any*() kfuncs

  Netfilter:

   - Relax set/map validation checks in nf_tables. Allow checking
     presence of an entry in a map without using the value

   - Increase ip_vs_conn_tab_bits range for 64BIT builds

   - Allow updating size of a set

   - Improve NAT tuple selection when connection is closing

  Driver API:

   - Integrate netdev with LED subsystem, to allow configuring HW
     "offloaded" blinking of LEDs based on link state and activity
     (i.e. packets coming in and out)

   - Support configuring rate selection pins of SFP modules

   - Factor Clause 73 auto-negotiation code out of the drivers, provide
     common helper routines

   - Add more fool-proof helpers for managing lifetime of MDIO devices
     associated with the PCS layer

   - Allow drivers to report advanced statistics related to Time Aware
     scheduler offload (taprio)

   - Allow opting out of VF statistics in link dump, to allow more VFs
     to fit into the message

   - Split devlink instance and devlink port operations

  New hardware / drivers:

   - Ethernet:
      - Synopsys EMAC4 IP support (stmmac)
      - Marvell 88E6361 8 port (5x1GE + 3x2.5GE) switches
      - Marvell 88E6250 7 port switches
      - Microchip LAN8650/1 Rev.B0 PHYs
      - MediaTek MT7981/MT7988 built-in 1GE PHY driver

   - WiFi:
      - Realtek RTL8192FU, 2.4 GHz, b/g/n mode, 2T2R, 300 Mbps
      - Realtek RTL8723DS (SDIO variant)
      - Realtek RTL8851BE

   - CAN:
      - Fintek F81604

  Drivers:

   - Ethernet NICs:
      - Intel (100G, ice):
         - support dynamic interrupt allocation
         - use meta data match instead of VF MAC addr on slow-path
      - nVidia/Mellanox:
         - extend link aggregation to handle 4, rather than just 2 ports
         - spawn sub-functions without any features by default
      - OcteonTX2:
         - support HTB (Tx scheduling/QoS) offload
         - make RSS hash generation configurable
         - support selecting Rx queue using TC filters
      - Wangxun (ngbe/txgbe):
         - add basic Tx/Rx packet offloads
         - add phylink support (SFP/PCS control)
      - Freescale/NXP (enetc):
         - report TAPRIO packet statistics
      - Solarflare/AMD:
         - support matching on IP ToS and UDP source port of outer
           header
         - VxLAN and GENEVE tunnel encapsulation over IPv4 or IPv6
         - add devlink dev info support for EF10

   - Virtual NICs:
      - Microsoft vNIC:
         - size the Rx indirection table based on requested
           configuration
         - support VLAN tagging
      - Amazon vNIC:
         - try to reuse Rx buffers if not fully consumed, useful for ARM
           servers running with 16kB pages
      - Google vNIC:
         - support TCP segmentation of >64kB frames

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - enable USXGMII (88E6191X)
      - Microchip:
         - lan966x: add support for Egress Stage 0 ACL engine
         - lan966x: support mapping packet priority to internal switch
           priority (based on PCP or DSCP)

   - Ethernet PHYs:
      - Broadcom PHYs:
         - support for Wake-on-LAN for BCM54210E/B50212E
         - report LPI counter
      - Microsemi PHYs: support RGMII delay configuration (VSC85xx)
      - Micrel PHYs: receive timestamp in the frame (LAN8841)
      - Realtek PHYs: support optional external PHY clock
      - Altera TSE PCS: merge the driver into Lynx PCS which it is a
        variant of

   - CAN: Kvaser PCIEcan:
      - support packet timestamping

   - WiFi:
      - Intel (iwlwifi):
         - major update for new firmware and Multi-Link Operation (MLO)
         - configuration rework to drop test devices and split the
           different families
         - support for segmented PNVM images and power tables
         - new vendor entries for PPAG (platform antenna gain) feature
      - Qualcomm 802.11ax (ath11k):
         - Multiple Basic Service Set Identifier (MBSSID) and Enhanced
           MBSSID Advertisement (EMA) support in AP mode
         - support factory test mode
      - RealTek (rtw89):
         - add RSSI based antenna diversity
         - support U-NII-4 channels on 5 GHz band
      - RealTek (rtl8xxxu):
         - AP mode support for 8188f
         - support USB RX aggregation for the newer chips"

* tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1602 commits)
  net: scm: introduce and use scm_recv_unix helper
  af_unix: Skip SCM_PIDFD if scm->pid is NULL.
  net: lan743x: Simplify comparison
  netlink: Add __sock_i_ino() for __netlink_diag_dump().
  net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addresses
  Revert "af_unix: Call scm_recv() only after scm_set_cred()."
  phylink: ReST-ify the phylink_pcs_neg_mode() kdoc
  libceph: Partially revert changes to support MSG_SPLICE_PAGES
  net: phy: mscc: fix packet loss due to RGMII delays
  net: mana: use vmalloc_array and vcalloc
  net: enetc: use vmalloc_array and vcalloc
  ionic: use vmalloc_array and vcalloc
  pds_core: use vmalloc_array and vcalloc
  gve: use vmalloc_array and vcalloc
  octeon_ep: use vmalloc_array and vcalloc
  net: usb: qmi_wwan: add u-blox 0x1312 composition
  perf trace: fix MSG_SPLICE_PAGES build error
  ipvlan: Fix return value of ipvlan_queue_xmit()
  netfilter: nf_tables: fix underflow in chain reference counter
  netfilter: nf_tables: unbind non-anonymous set if rule construction fails
  ...
2023-06-28 16:43:10 -07:00
David Howells
dc97391e66 sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)
Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-24 15:50:13 -07:00
Andrii Nakryiko
6c3eba1c5e bpf: Centralize permissions checks for all BPF map types
This allows to do more centralized decisions later on, and generally
makes it very explicit which maps are privileged and which are not
(e.g., LRU_HASH and LRU_PERCPU_HASH, which are privileged HASH variants,
as opposed to unprivileged HASH and HASH_PERCPU; now this is explicit
and easy to verify).

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230613223533.3689589-4-andrii@kernel.org
2023-06-19 14:04:04 +02:00
Lorenzo Stoakes
4c630f3074 mm/gup: remove vmas parameter from pin_user_pages()
We are now in a position where no caller of pin_user_pages() requires the
vmas parameter at all, so eliminate this parameter from the function and
all callers.

This clears the way to removing the vmas parameter from GUP altogether.

Link: https://lkml.kernel.org/r/195a99ae949c9f5cb589d2222b736ced96ec199a.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>	[qib]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>	[drivers/media]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:26 -07:00
Kal Conley
6ec7be9a2d xsk: Use pool->dma_pages to check for DMA
Compare pool->dma_pages instead of pool->dma_pages_cnt to check for an
active DMA mapping. pool->dma_pages needs to be read anyway to access
the map so this compiles to more efficient code.

Signed-off-by: Kal Conley <kal.conley@dectris.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230423180157.93559-1-kal.conley@dectris.com
2023-04-27 22:24:51 +02:00
Jakub Kicinski
c2865b1122 bpf-next-for-netdev
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Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-13

We've added 260 non-merge commits during the last 36 day(s) which contain
a total of 356 files changed, 21786 insertions(+), 11275 deletions(-).

The main changes are:

1) Rework BPF verifier log behavior and implement it as a rotating log
   by default with the option to retain old-style fixed log behavior,
   from Andrii Nakryiko.

2) Adds support for using {FOU,GUE} encap with an ipip device operating
   in collect_md mode and add a set of BPF kfuncs for controlling encap
   params, from Christian Ehrig.

3) Allow BPF programs to detect at load time whether a particular kfunc
   exists or not, and also add support for this in light skeleton,
   from Alexei Starovoitov.

4) Optimize hashmap lookups when key size is multiple of 4,
   from Anton Protopopov.

5) Enable RCU semantics for task BPF kptrs and allow referenced kptr
   tasks to be stored in BPF maps, from David Vernet.

6) Add support for stashing local BPF kptr into a map value via
   bpf_kptr_xchg(). This is useful e.g. for rbtree node creation
   for new cgroups, from Dave Marchevsky.

7) Fix BTF handling of is_int_ptr to skip modifiers to work around
   tracing issues where a program cannot be attached, from Feng Zhou.

8) Migrate a big portion of test_verifier unit tests over to
   test_progs -a verifier_* via inline asm to ease {read,debug}ability,
   from Eduard Zingerman.

9) Several updates to the instruction-set.rst documentation
   which is subject to future IETF standardization
   (https://lwn.net/Articles/926882/), from Dave Thaler.

10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register
    known bits information propagation, from Daniel Borkmann.

11) Add skb bitfield compaction work related to BPF with the overall goal
    to make more of the sk_buff bits optional, from Jakub Kicinski.

12) BPF selftest cleanups for build id extraction which stand on its own
    from the upcoming integration work of build id into struct file object,
    from Jiri Olsa.

13) Add fixes and optimizations for xsk descriptor validation and several
    selftest improvements for xsk sockets, from Kal Conley.

14) Add BPF links for struct_ops and enable switching implementations
    of BPF TCP cong-ctls under a given name by replacing backing
    struct_ops map, from Kui-Feng Lee.

15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable
    offset stack read as earlier Spectre checks cover this,
    from Luis Gerhorst.

16) Fix issues in copy_from_user_nofault() for BPF and other tracers
    to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner
    and Alexei Starovoitov.

17) Add --json-summary option to test_progs in order for CI tooling to
    ease parsing of test results, from Manu Bretelle.

18) Batch of improvements and refactoring to prep for upcoming
    bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator,
    from Martin KaFai Lau.

19) Improve bpftool's visual program dump which produces the control
    flow graph in a DOT format by adding C source inline annotations,
    from Quentin Monnet.

20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting
    the module name from BTF of the target and searching kallsyms of
    the correct module, from Viktor Malik.

21) Improve BPF verifier handling of '<const> <cond> <non_const>'
    to better detect whether in particular jmp32 branches are taken,
    from Yonghong Song.

22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock.
    A built-in cc or one from a kernel module is already able to write
    to app_limited, from Yixin Shen.

Conflicts:

Documentation/bpf/bpf_devel_QA.rst
  b7abcd9c65 ("bpf, doc: Link to submitting-patches.rst for general patch submission info")
  0f10f647f4 ("bpf, docs: Use internal linking for link to netdev subsystem doc")
https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/

include/net/ip_tunnels.h
  bc9d003dc4 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts")
  ac931d4cde ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices")
https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/

net/bpf/test_run.c
  e5995bc7e2 ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption")
  294635a816 ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES")
https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/
====================

Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13 16:43:38 -07:00
Kal Conley
1ba83f505c xsk: Elide base_addr comparison in xp_unaligned_validate_desc
Remove redundant (base_addr >= pool->addrs_cnt) comparison from the
conditional.

In particular, addr is computed as:

    addr = base_addr + offset

... where base_addr and offset are stored as 48-bit and 16-bit unsigned
integers, respectively. The above sum cannot overflow u64 since base_addr
has a maximum value of 0x0000ffffffffffff and offset has a maximum value
of 0xffff (implying a maximum sum of 0x000100000000fffe). Since overflow
is impossible, it follows that addr >= base_addr.

Now if (base_addr >= pool->addrs_cnt), then clearly:

    addr >= base_addr
         >= pool->addrs_cnt

Thus, (base_addr >= pool->addrs_cnt) implies (addr >= pool->addrs_cnt).
Subsequently, the former comparison is unnecessary in the conditional
since for any boolean expressions A and B, (A || B) && (A -> B) is
equivalent to B.

Signed-off-by: Kal Conley <kal.conley@dectris.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230411130025.19704-1-kal.conley@dectris.com
2023-04-13 15:00:11 +02:00
Kal Conley
0c5f48599b xsk: Simplify xp_aligned_validate_desc implementation
Perform the chunk boundary check like the page boundary check in
xp_desc_crosses_non_contig_pg(). This simplifies the implementation and
reduces the number of branches.

Signed-off-by: Kal Conley <kal.conley@dectris.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230410121841.643254-1-kal.conley@dectris.com
2023-04-13 14:51:02 +02:00
Kal Conley
d769ccaf95 xsk: Fix unaligned descriptor validation
Make sure unaligned descriptors that straddle the end of the UMEM are
considered invalid. Currently, descriptor validation is broken for
zero-copy mode which only checks descriptors at page granularity.
For example, descriptors in zero-copy mode that overrun the end of the
UMEM but not a page boundary are (incorrectly) considered valid. The
UMEM boundary check needs to happen before the page boundary and
contiguity checks in xp_desc_crosses_non_contig_pg(). Do this check in
xp_unaligned_validate_desc() instead like xp_check_unaligned() already
does.

Fixes: 2b43470add ("xsk: Introduce AF_XDP buffer allocation API")
Signed-off-by: Kal Conley <kal.conley@dectris.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230405235920.7305-2-kal.conley@dectris.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-04-06 09:53:05 -07:00
Nuno Gonçalves
5f5a7d8d8b xsk: allow remap of fill and/or completion rings
The remap of fill and completion rings was frowned upon as they
control the usage of UMEM which does not support concurrent use.
At the same time this would disallow the remap of these rings
into another process.

A possible use case is that the user wants to transfer the socket/
UMEM ownership to another process (via SYS_pidfd_getfd) and so
would need to also remap these rings.

This will have no impact on current usages and just relaxes the
remap limitation.

Signed-off-by: Nuno Gonçalves <nunog@fr24.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/r/20230324100222.13434-1-nunog@fr24.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 21:07:35 -07:00
Jakub Kicinski
dc0a7b5200 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
  6e9d51b1a5 ("net/mlx5e: Initialize link speed to zero")
  1bffcea429 ("net/mlx5e: Add devlink hairpin queues parameters")
https://lore.kernel.org/all/20230324120623.4ebbc66f@canb.auug.org.au/
https://lore.kernel.org/all/20230321211135.47711-1-saeed@kernel.org/

Adjacent changes:

drivers/net/phy/phy.c
  323fe43cf9 ("net: phy: Improved PHY error reporting in state machine")
  4203d84032 ("net: phy: Ensure state transitions are processed from phy_stop()")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-24 10:10:20 -07:00
JP Kobryn
d7ba4cc900 bpf: return long from bpf_map_ops funcs
This patch changes the return types of bpf_map_ops functions to long, where
previously int was returned. Using long allows for bpf programs to maintain
the sign bit in the absence of sign extension during situations where
inlined bpf helper funcs make calls to the bpf_map_ops funcs and a negative
error is returned.

The definitions of the helper funcs are generated from comments in the bpf
uapi header at `include/uapi/linux/bpf.h`. The return type of these
helpers was previously changed from int to long in commit bdb7b79b4c. For
any case where one of the map helpers call the bpf_map_ops funcs that are
still returning 32-bit int, a compiler might not include sign extension
instructions to properly convert the 32-bit negative value a 64-bit
negative value.

For example:
bpf assembly excerpt of an inlined helper calling a kernel function and
checking for a specific error:

; err = bpf_map_update_elem(&mymap, &key, &val, BPF_NOEXIST);
  ...
  46:	call   0xffffffffe103291c	; htab_map_update_elem
; if (err && err != -EEXIST) {
  4b:	cmp    $0xffffffffffffffef,%rax ; cmp -EEXIST,%rax

kernel function assembly excerpt of return value from
`htab_map_update_elem` returning 32-bit int:

movl $0xffffffef, %r9d
...
movl %r9d, %eax

...results in the comparison:
cmp $0xffffffffffffffef, $0x00000000ffffffef

Fixes: bdb7b79b4c ("bpf: Switch most helper return values from 32-bit int to 64-bit long")
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Link: https://lore.kernel.org/r/20230322194754.185781-3-inwardvessel@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-22 15:11:30 -07:00
Kal Conley
c7df4813b1 xsk: Add missing overflow check in xdp_umem_reg
The number of chunks can overflow u32. Make sure to return -EINVAL on
overflow. Also remove a redundant u32 cast assigning umem->npgs.

Fixes: bbff2f321a ("xsk: new descriptor addressing scheme")
Signed-off-by: Kal Conley <kal.conley@dectris.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230308174013.1114745-1-kal.conley@dectris.com
2023-03-16 16:02:55 +01:00
Yafang Shao
b4fd0d672b bpf, net: xskmap memory usage
A new helper is introduced to calculate xskmap memory usage.

The xfsmap memory usage can be dynamically changed when we add or remove
a xsk_map_node. Hence we need to track the count of xsk_map_node to get
its memory usage.

The result as follows,
- before
10: xskmap  name count_map  flags 0x0
        key 4B  value 4B  max_entries 65536  memlock 524288B

- after
10: xskmap  name count_map  flags 0x0 <<< no elements case
        key 4B  value 4B  max_entries 65536  memlock 524608B

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20230305124615.12358-17-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-07 09:33:43 -08:00
Xuan Zhuo
951bce29c8 xsk: add linux/vmalloc.h to xsk.c
Fix the failure of the compilation under the sh4.

Because we introduced remap_vmalloc_range() earlier, this has caused
the compilation failure on the sh4 platform. So this introduction of the
header file of linux/vmalloc.h.

config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20230221/202302210041.kpPQLlNQ-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=9f78bf330a66cd400b3e00f370f597e9fa939207
        git remote add net-next https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
        git fetch --no-tags net-next master
        git checkout 9f78bf330a
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=sh olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=sh SHELL=/bin/bash net/

Fixes: 9f78bf330a ("xsk: support use vaddr as ring")
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202302210041.kpPQLlNQ-lkp@intel.com/
Link: https://lore.kernel.org/r/20230221075140.46988-1-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-21 09:00:09 -08:00
Jakub Kicinski
ee8d72a157 bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-02-17

We've added 64 non-merge commits during the last 7 day(s) which contain
a total of 158 files changed, 4190 insertions(+), 988 deletions(-).

The main changes are:

1) Add a rbtree data structure following the "next-gen data structure"
   precedent set by recently-added linked-list, that is, by using
   kfunc + kptr instead of adding a new BPF map type, from Dave Marchevsky.

2) Add a new benchmark for hashmap lookups to BPF selftests,
   from Anton Protopopov.

3) Fix bpf_fib_lookup to only return valid neighbors and add an option
   to skip the neigh table lookup, from Martin KaFai Lau.

4) Add cgroup.memory=nobpf kernel parameter option to disable BPF memory
   accouting for container environments, from Yafang Shao.

5) Batch of ice multi-buffer and driver performance fixes,
   from Alexander Lobakin.

6) Fix a bug in determining whether global subprog's argument is
   PTR_TO_CTX, which is based on type names which breaks kprobe progs,
   from Andrii Nakryiko.

7) Prep work for future -mcpu=v4 LLVM option which includes usage of
   BPF_ST insn. Thus improve BPF_ST-related value tracking in verifier,
   from Eduard Zingerman.

8) More prep work for later building selftests with Memory Sanitizer
   in order to detect usages of undefined memory, from Ilya Leoshkevich.

9) Fix xsk sockets to check IFF_UP earlier to avoid a NULL pointer
   dereference via sendmsg(), from Maciej Fijalkowski.

10) Implement BPF trampoline for RV64 JIT compiler, from Pu Lehui.

11) Fix BPF memory allocator in combination with BPF hashtab where it could
    corrupt special fields e.g. used in bpf_spin_lock, from Hou Tao.

12) Fix LoongArch BPF JIT to always use 4 instructions for function
    address so that instruction sequences don't change between passes,
    from Hengqi Chen.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (64 commits)
  selftests/bpf: Add bpf_fib_lookup test
  bpf: Add BPF_FIB_LOOKUP_SKIP_NEIGH for bpf_fib_lookup
  riscv, bpf: Add bpf trampoline support for RV64
  riscv, bpf: Add bpf_arch_text_poke support for RV64
  riscv, bpf: Factor out emit_call for kernel and bpf context
  riscv: Extend patch_text for multiple instructions
  Revert "bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES"
  selftests/bpf: Add global subprog context passing tests
  selftests/bpf: Convert test_global_funcs test to test_loader framework
  bpf: Fix global subprog context argument resolution logic
  LoongArch, bpf: Use 4 instructions for function address in JIT
  bpf: bpf_fib_lookup should not return neigh in NUD_FAILED state
  bpf: Disable bh in bpf_test_run for xdp and tc prog
  xsk: check IFF_UP earlier in Tx path
  Fix typos in selftest/bpf files
  selftests/bpf: Use bpf_{btf,link,map,prog}_get_info_by_fd()
  samples/bpf: Use bpf_{btf,link,map,prog}_get_info_by_fd()
  bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd()
  libbpf: Use bpf_{btf,link,map,prog}_get_info_by_fd()
  libbpf: Introduce bpf_{btf,link,map,prog}_get_info_by_fd()
  ...
====================

Link: https://lore.kernel.org/r/20230217221737.31122-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-20 16:31:14 -08:00
Xuan Zhuo
9f78bf330a xsk: support use vaddr as ring
When we try to start AF_XDP on some machines with long running time, due
to the machine's memory fragmentation problem, there is no sufficient
contiguous physical memory that will cause the start failure.

If the size of the queue is 8 * 1024, then the size of the desc[] is
8 * 1024 * 8 = 16 * PAGE, but we also add struct xdp_ring size, so it is
16page+. This is necessary to apply for a 4-order memory. If there are a
lot of queues, it is difficult to these machine with long running time.

Here, that we actually waste 15 pages. 4-Order memory is 32 pages, but
we only use 17 pages.

This patch replaces __get_free_pages() by vmalloc() to allocate memory
to solve these problems.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-20 08:22:12 +00:00
Maciej Fijalkowski
1596dae2f1 xsk: check IFF_UP earlier in Tx path
Xsk Tx can be triggered via either sendmsg() or poll() syscalls. These
two paths share a call to common function xsk_xmit() which has two
sanity checks within. A pseudo code example to show the two paths:

__xsk_sendmsg() :                       xsk_poll():
if (unlikely(!xsk_is_bound(xs)))        if (unlikely(!xsk_is_bound(xs)))
    return -ENXIO;                          return mask;
if (unlikely(need_wait))                (...)
    return -EOPNOTSUPP;                 xsk_xmit()
mark napi id
(...)
xsk_xmit()

xsk_xmit():
if (unlikely(!(xs->dev->flags & IFF_UP)))
	return -ENETDOWN;
if (unlikely(!xs->tx))
	return -ENOBUFS;

As it can be observed above, in sendmsg() napi id can be marked on
interface that was not brought up and this causes a NULL ptr
dereference:

[31757.505631] BUG: kernel NULL pointer dereference, address: 0000000000000018
[31757.512710] #PF: supervisor read access in kernel mode
[31757.517936] #PF: error_code(0x0000) - not-present page
[31757.523149] PGD 0 P4D 0
[31757.525726] Oops: 0000 [#1] PREEMPT SMP NOPTI
[31757.530154] CPU: 26 PID: 95641 Comm: xdpsock Not tainted 6.2.0-rc5+ #40
[31757.536871] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019
[31757.547457] RIP: 0010:xsk_sendmsg+0xde/0x180
[31757.551799] Code: 00 75 a2 48 8b 00 a8 04 75 9b 84 d2 74 69 8b 85 14 01 00 00 85 c0 75 1b 48 8b 85 28 03 00 00 48 8b 80 98 00 00 00 48 8b 40 20 <8b> 40 18 89 85 14 01 00 00 8b bd 14 01 00 00 81 ff 00 01 00 00 0f
[31757.570840] RSP: 0018:ffffc90034f27dc0 EFLAGS: 00010246
[31757.576143] RAX: 0000000000000000 RBX: ffffc90034f27e18 RCX: 0000000000000000
[31757.583389] RDX: 0000000000000001 RSI: ffffc90034f27e18 RDI: ffff88984cf3c100
[31757.590631] RBP: ffff88984714a800 R08: ffff88984714a800 R09: 0000000000000000
[31757.597877] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffffa
[31757.605123] R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000000
[31757.612364] FS:  00007fb4c5931180(0000) GS:ffff88afdfa00000(0000) knlGS:0000000000000000
[31757.620571] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[31757.626406] CR2: 0000000000000018 CR3: 000000184b41c003 CR4: 00000000007706e0
[31757.633648] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[31757.640894] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[31757.648139] PKRU: 55555554
[31757.650894] Call Trace:
[31757.653385]  <TASK>
[31757.655524]  sock_sendmsg+0x8f/0xa0
[31757.659077]  ? sockfd_lookup_light+0x12/0x70
[31757.663416]  __sys_sendto+0xfc/0x170
[31757.667051]  ? do_sched_setscheduler+0xdb/0x1b0
[31757.671658]  __x64_sys_sendto+0x20/0x30
[31757.675557]  do_syscall_64+0x38/0x90
[31757.679197]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
[31757.687969] Code: 8e f6 ff 44 8b 4c 24 2c 4c 8b 44 24 20 41 89 c4 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 3a 44 89 e7 48 89 44 24 08 e8 b5 8e f6 ff 48
[31757.707007] RSP: 002b:00007ffd49c73c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
[31757.714694] RAX: ffffffffffffffda RBX: 000055a996565380 RCX: 00007fb4c5727c16
[31757.721939] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
[31757.729184] RBP: 0000000000000040 R08: 0000000000000000 R09: 0000000000000000
[31757.736429] R10: 0000000000000040 R11: 0000000000000293 R12: 0000000000000000
[31757.743673] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[31757.754940]  </TASK>

To fix this, let's make xsk_xmit a function that will be responsible for
generic Tx, where RCU is handled accordingly and pull out sanity checks
and xs->zc handling. Populate sanity checks to __xsk_sendmsg() and
xsk_poll().

Fixes: ca2e1a6270 ("xsk: Mark napi_id on sendmsg()")
Fixes: 18b1ab7aa7 ("xsk: Fix race at socket teardown")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230215143309.13145-1-maciej.fijalkowski@intel.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2023-02-17 16:05:28 +01:00
Jason Xing
fe33311c3e net: no longer support SOCK_REFCNT_DEBUG feature
Commit e48c414ee6 ("[INET]: Generalise the TCP sock ID lookup routines")
commented out the definition of SOCK_REFCNT_DEBUG in 2005 and later another
commit 463c84b97f ("[NET]: Introduce inet_connection_sock") removed it.
Since we could track all of them through bpf and kprobe related tools
and the feature could print loads of information which might not be
that helpful even under a little bit pressure, the whole feature which
has been inactive for many years is no longer supported.

Link: https://lore.kernel.org/lkml/20230211065153.54116-1-kerneljasonxing@gmail.com/
Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-15 10:25:21 +00:00
Marek Majtyka
0ae0cb2bb2 xsk: add usage of XDP features flags
Change necessary condition check for XSK from ndo functions to
xdp features flags.

Signed-off-by: Marek Majtyka <alardam@gmail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/45a98ec67b4556a6a22dfd85df3eb8276beeeb74.1675245258.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-02 20:48:23 -08:00
Toke Høiland-Jørgensen
32637e3300 bpf: Expand map key argument of bpf_redirect_map to u64
For queueing packets in XDP we want to add a new redirect map type with
support for 64-bit indexes. To prepare fore this, expand the width of the
'key' argument to the bpf_redirect_map() helper. Since BPF registers are
always 64-bit, this should be safe to do after the fact.

Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20221108140601.149971-3-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-15 09:00:27 -08:00
Jakub Kicinski
e52f7c1ddf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in the left-over fixes before the net-next pull-request.

Conflicts:

drivers/net/ethernet/mediatek/mtk_ppe.c
  ae3ed15da5 ("net: ethernet: mtk_eth_soc: fix state in __mtk_foe_entry_clear")
  9d8cb4c096 ("net: ethernet: mtk_eth_soc: add foe_entry_size to mtk_eth_soc")
https://lore.kernel.org/all/6cb6893b-4921-a068-4c30-1109795110bb@tessares.net/

kernel/bpf/helpers.c
  8addbfc7b3 ("bpf: Gate dynptr API behind CAP_BPF")
  5679ff2f13 ("bpf: Move bpf_loop and bpf_for_each_map_elem under CAP_BPF")
  8a67f2de9b ("bpf: expose bpf_strtol and bpf_strtoul to all program types")
https://lore.kernel.org/all/20221003201957.13149-1-daniel@iogearbox.net/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-03 17:44:18 -07:00
Maxim Mikityanskiy
9ca66afe73 xsk: Expose min chunk size to drivers
Drivers should be aware of the range of valid UMEM chunk sizes to be
able to allocate their internal structures of an appropriate size. It
will be used by mlx5e in the following patches.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
CC: "Björn Töpel" <bjorn@kernel.org>
CC: Magnus Karlsson <magnus.karlsson@intel.com>
CC: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-30 07:55:45 -07:00
Jalal Mostafa
60240bc261 xsk: Inherit need_wakeup flag for shared sockets
The flag for need_wakeup is not set for xsks with `XDP_SHARED_UMEM`
flag and of different queue ids and/or devices. They should inherit
the flag from the first socket buffer pool since no flags can be
specified once `XDP_SHARED_UMEM` is specified.

Fixes: b5aea28dca ("xsk: Add shared umem support between queue ids")
Signed-off-by: Jalal Mostafa <jalal.a.mostapha@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220921135701.10199-1-jalal.a.mostapha@gmail.com
2022-09-22 17:16:22 +02:00
Maciej Fijalkowski
c00c446168 xsk: Fix backpressure mechanism on Tx
Commit d678cbd2f8 ("xsk: Fix handling of invalid descriptors in XSK TX
batching API") fixed batch API usage against set of descriptors with
invalid ones but introduced a problem when AF_XDP SW rings are smaller
than HW ones. Mismatch of reported Tx'ed frames between HW generator and
user space app was observed. It turned out that backpressure mechanism
became a bottleneck when the amount of produced descriptors to CQ is
lower than what we grabbed from XSK Tx ring.

Say that 512 entries had been taken from XSK Tx ring but we had only 490
free entries in CQ. Then callsite (ZC driver) will produce only 490
entries onto HW Tx ring but 512 entries will be released from Tx ring
and this is what will be seen by the user space.

In order to fix this case, mix XSK Tx/CQ ring interractions by moving
around internal functions and changing call order:

*  pull out xskq_prod_nb_free() from xskq_prod_reserve_addr_batch()
   up to xsk_tx_peek_release_desc_batch();
** move xskq_cons_release_n() into xskq_cons_read_desc_batch()

After doing so, algorithm can be described as follows:

1. lookup Tx entries
2. use value from 1. to reserve space in CQ (*)
3. Read from Tx ring as much descriptors as value from 2
 3a. release descriptors from XSK Tx ring (**)
4. Finally produce addresses to CQ

Fixes: d678cbd2f8 ("xsk: Fix handling of invalid descriptors in XSK TX batching API")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220830121705.8618-1-maciej.fijalkowski@intel.com
2022-08-31 20:52:09 +02:00
Magnus Karlsson
58ca14ed98 xsk: Fix corrupted packets for XDP_SHARED_UMEM
Fix an issue in XDP_SHARED_UMEM mode together with aligned mode where
packets are corrupted for the second and any further sockets bound to
the same umem. In other words, this does not affect the first socket
bound to the umem. The culprit for this bug is that the initialization
of the DMA addresses for the pre-populated xsk buffer pool entries was
not performed for any socket but the first one bound to the umem. Only
the linear array of DMA addresses was populated. Fix this by populating
the DMA addresses in the xsk buffer pool for every socket bound to the
same umem.

Fixes: 94033cd8e7 ("xsk: Optimize for aligned case")
Reported-by: Alasdair McWilliam <alasdair.mcwilliam@outlook.com>
Reported-by: Intrusion Shield Team <dnevil@intrusion.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alasdair McWilliam <alasdair.mcwilliam@outlook.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/xdp-newbies/6205E10C-292E-4995-9D10-409649354226@outlook.com/
Link: https://lore.kernel.org/bpf/20220812113259.531-1-magnus.karlsson@gmail.com
2022-08-15 17:26:07 +02:00
Maciej Fijalkowski
ca2e1a6270 xsk: Mark napi_id on sendmsg()
When application runs in busy poll mode and does not receive a single
packet but only sends them, it is currently impossible to get into
napi_busy_loop() as napi_id is only marked on Rx side in xsk_rcv_check().
In there, napi_id is being taken from xdp_rxq_info carried by xdp_buff.
From Tx perspective, we do not have access to it. What we have handy is
the xsk pool.

Xsk pool works on a pool of internal xdp_buff wrappers called xdp_buff_xsk.
AF_XDP ZC enabled drivers call xp_set_rxq_info() so each of xdp_buff_xsk
has a valid pointer to xdp_rxq_info of underlying queue. Therefore, on Tx
side, napi_id can be pulled from xs->pool->heads[0].xdp.rxq->napi_id. Hide
this pointer chase under helper function, xsk_pool_get_napi_id().

Do this only for sockets working in ZC mode as otherwise rxq pointers would
not be initialized.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220707130842.49408-1-maciej.fijalkowski@intel.com
2022-07-14 22:45:34 +02:00
Jakub Kicinski
83ec88d81a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-07 12:07:37 -07:00
Ivan Malov
512d1999b8 xsk: Clear page contiguity bit when unmapping pool
When a XSK pool gets mapped, xp_check_dma_contiguity() adds bit 0x1
to pages' DMA addresses that go in ascending order and at 4K stride.

The problem is that the bit does not get cleared before doing unmap.
As a result, a lot of warnings from iommu_dma_unmap_page() are seen
in dmesg, which indicates that lookups by iommu_iova_to_phys() fail.

Fixes: 2b43470add ("xsk: Introduce AF_XDP buffer allocation API")
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220628091848.534803-1-ivan.malov@oktetlabs.ru
2022-06-28 22:49:04 +02:00
Jakub Kicinski
93817be8b6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-23 12:33:24 -07:00
Jakub Kicinski
9fb424c4c2 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-06-17

We've added 72 non-merge commits during the last 15 day(s) which contain
a total of 92 files changed, 4582 insertions(+), 834 deletions(-).

The main changes are:

1) Add 64 bit enum value support to BTF, from Yonghong Song.

2) Implement support for sleepable BPF uprobe programs, from Delyan Kratunov.

3) Add new BPF helpers to issue and check TCP SYN cookies without binding to a
   socket especially useful in synproxy scenarios, from Maxim Mikityanskiy.

4) Fix libbpf's internal USDT address translation logic for shared libraries as
   well as uprobe's symbol file offset calculation, from Andrii Nakryiko.

5) Extend libbpf to provide an API for textual representation of the various
   map/prog/attach/link types and use it in bpftool, from Daniel Müller.

6) Provide BTF line info for RV64 and RV32 JITs, and fix a put_user bug in the
   core seen in 32 bit when storing BPF function addresses, from Pu Lehui.

7) Fix libbpf's BTF pointer size guessing by adding a list of various aliases
   for 'long' types, from Douglas Raillard.

8) Fix bpftool to readd setting rlimit since probing for memcg-based accounting
   has been unreliable and caused a regression on COS, from Quentin Monnet.

9) Fix UAF in BPF cgroup's effective program computation triggered upon BPF link
   detachment, from Tadeusz Struk.

10) Fix bpftool build bootstrapping during cross compilation which was pointing
    to the wrong AR process, from Shahab Vahedi.

11) Fix logic bug in libbpf's is_pow_of_2 implementation, from Yuze Chi.

12) BPF hash map optimization to avoid grabbing spinlocks of all CPUs when there
    is no free element. Also add a benchmark as reproducer, from Feng Zhou.

13) Fix bpftool's codegen to bail out when there's no BTF, from Michael Mullin.

14) Various minor cleanup and improvements all over the place.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
  bpf: Fix bpf_skc_lookup comment wrt. return type
  bpf: Fix non-static bpf_func_proto struct definitions
  selftests/bpf: Don't force lld on non-x86 architectures
  selftests/bpf: Add selftests for raw syncookie helpers in TC mode
  bpf: Allow the new syncookie helpers to work with SKBs
  selftests/bpf: Add selftests for raw syncookie helpers
  bpf: Add helpers to issue and check SYN cookies in XDP
  bpf: Allow helpers to accept pointers with a fixed size
  bpf: Fix documentation of th_len in bpf_tcp_{gen,check}_syncookie
  selftests/bpf: add tests for sleepable (uk)probes
  libbpf: add support for sleepable uprobe programs
  bpf: allow sleepable uprobe programs to attach
  bpf: implement sleepable uprobes by chaining gps
  bpf: move bpf_prog to bpf.h
  libbpf: Fix internal USDT address translation logic for shared libraries
  samples/bpf: Check detach prog exist or not in xdp_fwd
  selftests/bpf: Avoid skipping certain subtests
  selftests/bpf: Fix test_varlen verification failure with latest llvm
  bpftool: Do not check return value from libbpf_set_strict_mode()
  Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"
  ...
====================

Link: https://lore.kernel.org/r/20220617220836.7373-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-17 19:35:19 -07:00
Ciara Loftus
a6e944f25c xsk: Fix generic transmit when completion queue reservation fails
Two points of potential failure in the generic transmit function are:

  1. completion queue (cq) reservation failure.
  2. skb allocation failure

Originally the cq reservation was performed first, followed by the skb
allocation. Commit 675716400d ("xdp: fix possible cq entry leak")
reversed the order because at the time there was no mechanism available
to undo the cq reservation which could have led to possible cq entry leaks
in the event of skb allocation failure. However if the skb allocation is
performed first and the cq reservation then fails, the xsk skb destructor
is called which blindly adds the skb address to the already full cq leading
to undefined behavior.

This commit restores the original order (cq reservation followed by skb
allocation) and uses the xskq_prod_cancel helper to undo the cq reserve
in event of skb allocation failure.

Fixes: 675716400d ("xdp: fix possible cq entry leak")
Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220614070746.8871-1-ciara.loftus@intel.com
2022-06-14 16:49:29 +02:00
Maciej Fijalkowski
d678cbd2f8 xsk: Fix handling of invalid descriptors in XSK TX batching API
xdpxceiver run on a AF_XDP ZC enabled driver revealed a problem with XSK
Tx batching API. There is a test that checks how invalid Tx descriptors
are handled by AF_XDP. Each valid descriptor is followed by invalid one
on Tx side whereas the Rx side expects only to receive a set of valid
descriptors.

In current xsk_tx_peek_release_desc_batch() function, the amount of
available descriptors is hidden inside xskq_cons_peek_desc_batch(). This
can be problematic in cases where invalid descriptors are present due to
the fact that xskq_cons_peek_desc_batch() returns only a count of valid
descriptors. This means that it is impossible to properly update XSK
ring state when calling xskq_cons_release_n().

To address this issue, pull out the contents of
xskq_cons_peek_desc_batch() so that callers (currently only
xsk_tx_peek_release_desc_batch()) will always be able to update the
state of ring properly, as total count of entries is now available and
use this value as an argument in xskq_cons_release_n(). By
doing so, xskq_cons_peek_desc_batch() can be dropped altogether.

Fixes: 9349eb3a9d ("xsk: Introduce batched Tx descriptor interfaces")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220607142200.576735-1-maciej.fijalkowski@intel.com
2022-06-08 16:20:07 +02:00
Ke Liu
21f1481a8d xdp: Directly use ida_alloc()/free() APIs
Use ida_alloc() / ida_free() instead of the deprecated ida_simple_get() /
ida_simple_remove().

Signed-off-by: Ke Liu <liuke94@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20220527064609.2358482-1-liuke94@huawei.com
2022-06-02 16:25:30 -07:00
Jakub Kicinski
0e55546b18 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/linux/netdevice.h
net/core/dev.c
  6510ea973d ("net: Use this_cpu_inc() to increment net->core_stats")
  794c24e992 ("net-core: rx_otherhost_dropped to core_stats")
https://lore.kernel.org/all/20220428111903.5f4304e0@canb.auug.org.au/

drivers/net/wan/cosa.c
  d48fea8401 ("net: cosa: fix error check return value of register_chrdev()")
  89fbca3307 ("net: wan: remove support for COSA and SRP synchronous serial boards")
https://lore.kernel.org/all/20220428112130.1f689e5e@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-28 13:02:01 -07:00
Menglong Dong
c317ab71fa bpf: Compute map_btf_id during build time
For now, the field 'map_btf_id' in 'struct bpf_map_ops' for all map
types are computed during vmlinux-btf init:

  btf_parse_vmlinux() -> btf_vmlinux_map_ids_init()

It will lookup the btf_type according to the 'map_btf_name' field in
'struct bpf_map_ops'. This process can be done during build time,
thanks to Jiri's resolve_btfids.

selftest of map_ptr has passed:

  $96 map_ptr:OK
  Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-04-26 11:35:21 -07:00
Maciej Fijalkowski
ba3beec2ec xsk: Fix possible crash when multiple sockets are created
Fix a crash that happens if an Rx only socket is created first, then a
second socket is created that is Tx only and bound to the same umem as
the first socket and also the same netdev and queue_id together with the
XDP_SHARED_UMEM flag. In this specific case, the tx_descs array page
pool was not created by the first socket as it was an Rx only socket.
When the second socket is bound it needs this tx_descs array of this
shared page pool as it has a Tx component, but unfortunately it was
never allocated, leading to a crash. Note that this array is only used
for zero-copy drivers using the batched Tx APIs, currently only ice and
i40e.

[ 5511.150360] BUG: kernel NULL pointer dereference, address: 0000000000000008
[ 5511.158419] #PF: supervisor write access in kernel mode
[ 5511.164472] #PF: error_code(0x0002) - not-present page
[ 5511.170416] PGD 0 P4D 0
[ 5511.173347] Oops: 0002 [#1] PREEMPT SMP PTI
[ 5511.178186] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G            E     5.18.0-rc1+ #97
[ 5511.187245] Hardware name: Intel Corp. GRANTLEY/GRANTLEY, BIOS GRRFCRB1.86B.0276.D07.1605190235 05/19/2016
[ 5511.198418] RIP: 0010:xsk_tx_peek_release_desc_batch+0x198/0x310
[ 5511.205375] Code: c0 83 c6 01 84 c2 74 6d 8d 46 ff 23 07 44 89 e1 48 83 c0 14 48 c1 e1 04 48 c1 e0 04 48 03 47 10 4c 01 c1 48 8b 50 08 48 8b 00 <48> 89 51 08 48 89 01 41 80 bd d7 00 00 00 00 75 82 48 8b 19 49 8b
[ 5511.227091] RSP: 0018:ffffc90000003dd0 EFLAGS: 00010246
[ 5511.233135] RAX: 0000000000000000 RBX: ffff88810c8da600 RCX: 0000000000000000
[ 5511.241384] RDX: 000000000000003c RSI: 0000000000000001 RDI: ffff888115f555c0
[ 5511.249634] RBP: ffffc90000003e08 R08: 0000000000000000 R09: ffff889092296b48
[ 5511.257886] R10: 0000ffffffffffff R11: ffff889092296800 R12: 0000000000000000
[ 5511.266138] R13: ffff88810c8db500 R14: 0000000000000040 R15: 0000000000000100
[ 5511.274387] FS:  0000000000000000(0000) GS:ffff88903f800000(0000) knlGS:0000000000000000
[ 5511.283746] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5511.290389] CR2: 0000000000000008 CR3: 00000001046e2001 CR4: 00000000003706f0
[ 5511.298640] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 5511.306892] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 5511.315142] Call Trace:
[ 5511.317972]  <IRQ>
[ 5511.320301]  ice_xmit_zc+0x68/0x2f0 [ice]
[ 5511.324977]  ? ktime_get+0x38/0xa0
[ 5511.328913]  ice_napi_poll+0x7a/0x6a0 [ice]
[ 5511.333784]  __napi_poll+0x2c/0x160
[ 5511.337821]  net_rx_action+0xdd/0x200
[ 5511.342058]  __do_softirq+0xe6/0x2dd
[ 5511.346198]  irq_exit_rcu+0xb5/0x100
[ 5511.350339]  common_interrupt+0xa4/0xc0
[ 5511.354777]  </IRQ>
[ 5511.357201]  <TASK>
[ 5511.359625]  asm_common_interrupt+0x1e/0x40
[ 5511.364466] RIP: 0010:cpuidle_enter_state+0xd2/0x360
[ 5511.370211] Code: 49 89 c5 0f 1f 44 00 00 31 ff e8 e9 00 7b ff 45 84 ff 74 12 9c 58 f6 c4 02 0f 85 72 02 00 00 31 ff e8 02 0c 80 ff fb 45 85 f6 <0f> 88 11 01 00 00 49 63 c6 4c 2b 2c 24 48 8d 14 40 48 8d 14 90 49
[ 5511.391921] RSP: 0018:ffffffff82a03e60 EFLAGS: 00000202
[ 5511.397962] RAX: ffff88903f800000 RBX: 0000000000000001 RCX: 000000000000001f
[ 5511.406214] RDX: 0000000000000000 RSI: ffffffff823400b9 RDI: ffffffff8234c046
[ 5511.424646] RBP: ffff88810a384800 R08: 000005032a28c046 R09: 0000000000000008
[ 5511.443233] R10: 000000000000000b R11: 0000000000000006 R12: ffffffff82bcf700
[ 5511.461922] R13: 000005032a28c046 R14: 0000000000000001 R15: 0000000000000000
[ 5511.480300]  cpuidle_enter+0x29/0x40
[ 5511.494329]  do_idle+0x1c7/0x250
[ 5511.507610]  cpu_startup_entry+0x19/0x20
[ 5511.521394]  start_kernel+0x649/0x66e
[ 5511.534626]  secondary_startup_64_no_verify+0xc3/0xcb
[ 5511.549230]  </TASK>

Detect such case during bind() and allocate this memory region via newly
introduced xp_alloc_tx_descs(). Also, use kvcalloc instead of kcalloc as
for other buffer pool allocations, so that it matches the kvfree() from
xp_destroy().

Fixes: d1bc532e99 ("i40e: xsk: Move tmp desc array from driver to pool")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220425153745.481322-1-maciej.fijalkowski@intel.com
2022-04-26 16:19:54 +02:00
Maciej Fijalkowski
0fb53aabc5 xsk: Drop ternary operator from xskq_cons_has_entries
Simplify the mentioned helper function by removing ternary operator. The
expression that is there outputs the boolean value by itself.

This helper might be used in the hot path so this simplification can
also be considered as micro optimization.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220413153015.453864-15-maciej.fijalkowski@intel.com
2022-04-15 21:11:17 +02:00
Maciej Fijalkowski
2be4a677cc xsk: Diversify return codes in xsk_rcv_check()
Inspired by patch that made xdp_do_redirect() return values for XSKMAP
more meaningful, return -ENXIO instead of -EINVAL for socket being
unbound in xsk_rcv_check() as this is the usual value that is returned
for such event. In turn, it is now possible to easily distinguish what
went wrong, which is a bit harder when for both cases checked, -EINVAL
was returned.

Return codes can be counted in a nice way via bpftrace oneliner that
Jesper has shown:

bpftrace -e 'tracepoint:xdp:xdp_redirect* {@err[-args->err] = count();}'

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20220413153015.453864-3-maciej.fijalkowski@intel.com
2022-04-15 21:09:44 +02:00
Björn Töpel
c6c1f11b69 xsk: Improve xdp_do_redirect() error codes
The error codes returned by xdp_do_redirect() when redirecting a frame
to an AF_XDP socket has not been very useful. A driver could not
distinguish between different errors. Prior this change the following
codes where used:

Socket not bound or incorrect queue/netdev: EINVAL
XDP frame/AF_XDP buffer size mismatch: ENOSPC
Could not allocate buffer (copy mode): ENOSPC
AF_XDP Rx buffer full: ENOSPC

After this change:

Socket not bound or incorrect queue/netdev: EINVAL
XDP frame/AF_XDP buffer size mismatch: ENOSPC
Could not allocate buffer (copy mode): ENOMEM
AF_XDP Rx buffer full: ENOBUFS

An AF_XDP zero-copy driver can now potentially determine if the
failure was due to a full Rx buffer, and if so stop processing more
frames, yielding to the userland AF_XDP application.

Signed-off-by: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20220413153015.453864-2-maciej.fijalkowski@intel.com
2022-04-15 21:09:44 +02:00
Maciej Fijalkowski
8de8b71b78 xsk: Fix l2fwd for copy mode + busy poll combo
While checking AF_XDP copy mode combined with busy poll, strange
results were observed. rxdrop and txonly scenarios worked fine, but
l2fwd broke immediately.

After a deeper look, it turned out that for l2fwd, Tx side was exiting
early due to xsk_no_wakeup() returning true and in the end
xsk_generic_xmit() was never called. Note that AF_XDP Tx in copy mode
is syscall steered, so the current behavior is broken.

Txonly scenario only worked due to the fact that
sk_mark_napi_id_once_xdp() was never called - since Rx side is not in
the picture for this case and mentioned function is called in
xsk_rcv_check(), sk::sk_napi_id was never set, which in turn meant that
xsk_no_wakeup() was returning false (see the sk->sk_napi_id >=
MIN_NAPI_ID check in there).

To fix this, prefer busy poll in xsk_sendmsg() only when zero copy is
enabled on a given AF_XDP socket. By doing so, busy poll in copy mode
would not exit early on Tx side and eventually xsk_generic_xmit() will
be called.

Fixes: a0731952d9 ("xsk: Add busy-poll support for {recv,send}msg()")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220406155804.434493-1-maciej.fijalkowski@intel.com
2022-04-07 23:09:08 +02:00
Magnus Karlsson
a95a4d9b39 xsk: Do not write NULL in SW ring at allocation failure
For the case when xp_alloc_batch() is used but the batched allocation
cannot be used, there is a slow path that uses the non-batched
xp_alloc(). When it fails to allocate an entry, it returns NULL. The
current code wrote this NULL into the entry of the provided results
array (pointer to the driver SW ring usually) and returned. This might
not be what the driver expects and to make things simpler, just write
successfully allocated xdp_buffs into the SW ring,. The driver might
have information in there that is still important after an allocation
failure.

Note that at this point in time, there are no drivers using
xp_alloc_batch() that could trigger this slow path. But one might get
added.

Fixes: 47e4075df3 ("xsk: Batched buffer allocation for the pool")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220328142123.170157-2-maciej.fijalkowski@intel.com
2022-03-28 19:56:28 -07:00
Jakub Kicinski
89695196f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in overtime fixes, no conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-23 10:53:49 -07:00
Magnus Karlsson
18b1ab7aa7 xsk: Fix race at socket teardown
Fix a race in the xsk socket teardown code that can lead to a NULL pointer
dereference splat. The current xsk unbind code in xsk_unbind_dev() starts by
setting xs->state to XSK_UNBOUND, sets xs->dev to NULL and then waits for any
NAPI processing to terminate using synchronize_net(). After that, the release
code starts to tear down the socket state and free allocated memory.

  BUG: kernel NULL pointer dereference, address: 00000000000000c0
  PGD 8000000932469067 P4D 8000000932469067 PUD 0
  Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 25 PID: 69132 Comm: grpcpp_sync_ser Tainted: G          I       5.16.0+ #2
  Hardware name: Dell Inc. PowerEdge R730/0599V5, BIOS 1.2.10 03/09/2015
  RIP: 0010:__xsk_sendmsg+0x2c/0x690
  [...]
  RSP: 0018:ffffa2348bd13d50 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 0000000000000040 RCX: ffff8d5fc632d258
  RDX: 0000000000400000 RSI: ffffa2348bd13e10 RDI: ffff8d5fc5489800
  RBP: ffffa2348bd13db0 R08: 0000000000000000 R09: 00007ffffffff000
  R10: 0000000000000000 R11: 0000000000000000 R12: ffff8d5fc5489800
  R13: ffff8d5fcb0f5140 R14: ffff8d5fcb0f5140 R15: 0000000000000000
  FS:  00007f991cff9400(0000) GS:ffff8d6f1f700000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000000000c0 CR3: 0000000114888005 CR4: 00000000001706e0
  Call Trace:
  <TASK>
  ? aa_sk_perm+0x43/0x1b0
  xsk_sendmsg+0xf0/0x110
  sock_sendmsg+0x65/0x70
  __sys_sendto+0x113/0x190
  ? debug_smp_processor_id+0x17/0x20
  ? fpregs_assert_state_consistent+0x23/0x50
  ? exit_to_user_mode_prepare+0xa5/0x1d0
  __x64_sys_sendto+0x29/0x30
  do_syscall_64+0x3b/0xc0
  entry_SYSCALL_64_after_hwframe+0x44/0xae

There are two problems with the current code. First, setting xs->dev to NULL
before waiting for all users to stop using the socket is not correct. The
entry to the data plane functions xsk_poll(), xsk_sendmsg(), and xsk_recvmsg()
are all guarded by a test that xs->state is in the state XSK_BOUND and if not,
it returns right away. But one process might have passed this test but still
have not gotten to the point in which it uses xs->dev in the code. In this
interim, a second process executing xsk_unbind_dev() might have set xs->dev to
NULL which will lead to a crash for the first process. The solution here is
just to get rid of this NULL assignment since it is not used anymore. Before
commit 42fddcc7c6 ("xsk: use state member for socket synchronization"),
xs->dev was the gatekeeper to admit processes into the data plane functions,
but it was replaced with the state variable xs->state in the aforementioned
commit.

The second problem is that synchronize_net() does not wait for any process in
xsk_poll(), xsk_sendmsg(), or xsk_recvmsg() to complete, which means that the
state they rely on might be cleaned up prematurely. This can happen when the
notifier gets called (at driver unload for example) as it uses xsk_unbind_dev().
Solve this by extending the RCU critical region from just the ndo_xsk_wakeup
to the whole functions mentioned above, so that both the test of xs->state ==
XSK_BOUND and the last use of any member of xs is covered by the RCU critical
section. This will guarantee that when synchronize_net() completes, there will
be no processes left executing xsk_poll(), xsk_sendmsg(), or xsk_recvmsg() and
state can be cleaned up safely. Note that we need to drop the RCU lock for the
skb xmit path as it uses functions that might sleep. Due to this, we have to
retest the xs->state after we grab the mutex that protects the skb xmit code
from, among a number of things, an xsk_unbind_dev() being executed from the
notifier at the same time.

Fixes: 42fddcc7c6 ("xsk: use state member for socket synchronization")
Reported-by: Elza Mathew <elza.mathew@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20220228094552.10134-1-magnus.karlsson@gmail.com
2022-02-28 15:39:53 +01:00
Magnus Karlsson
d1bc532e99 i40e: xsk: Move tmp desc array from driver to pool
Move desc_array from the driver to the pool. The reason behind this is
that we can then reuse this array as a temporary storage for descriptors
in all zero-copy drivers that use the batched interface. This will make
it easier to add batching to more drivers.

i40e is the only driver that has a batched Tx zero-copy
implementation, so no need to touch any other driver.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Link: https://lore.kernel.org/bpf/20220125160446.78976-6-maciej.fijalkowski@intel.com
2022-01-27 17:25:32 +01:00
Jakub Kicinski
8033c6c2fe bpf: remove unused static inlines
Remove two dead stubs, sk_msg_clear_meta() was never
used, use of xskq_cons_is_full() got replaced by
xsk_tx_writeable() in v5.10.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20220126185412.2776254-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-26 21:17:53 -08:00
Jakub Kicinski
b9adba350a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-05 14:36:10 -08:00