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2023-04-03net: simplify handling of dsa_ndo_eth_ioctl() return codeVladimir Oltean1-1/+1
In the expression "x == 0 || x != -95", the term "x == 0" does not change the expression's logical value, because 0 != -95, and so, if x is 0, the expression would still be true by virtue of the second term. If x is non-zero, the expression depends on the truth value of the second term anyway. As such, the first term is redundant and can be deleted. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-03net: don't abuse "default" case for unknown ioctl in dev_ifsioc()Vladimir Oltean1-23/+19
The "switch (cmd)" block from dev_ifsioc() gained a bit too much unnecessary manual handling of "cmd" in the "default" case, starting with the private ioctls. Clean that up by using the "ellipsis" gcc extension, adding separate cases for the rest of the ioctls, and letting the default case only return -EINVAL. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-02net: don't let netpoll invoke NAPI if in xmit contextJakub Kicinski1-1/+18
Commit 0db3dc73f7a3 ("[NETPOLL]: tx lock deadlock fix") narrowed down the region under netif_tx_trylock() inside netpoll_send_skb(). (At that point in time netif_tx_trylock() would lock all queues of the device.) Taking the tx lock was problematic because driver's cleanup method may take the same lock. So the change made us hold the xmit lock only around xmit, and expected the driver to take care of locking within ->ndo_poll_controller(). Unfortunately this only works if netpoll isn't itself called with the xmit lock already held. Netpoll code is careful and uses trylock(). The drivers, however, may be using plain lock(). Printing while holding the xmit lock is going to result in rare deadlocks. Luckily we record the xmit lock owners, so we can scan all the queues, the same way we scan NAPI owners. If any of the xmit locks is held by the local CPU we better not attempt any polling. It would be nice if we could narrow down the check to only the NAPIs and the queue we're trying to use. I don't see a way to do that now. Reported-by: Roman Gushchin <roman.gushchin@linux.dev> Fixes: 0db3dc73f7a3 ("[NETPOLL]: tx lock deadlock fix") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-30net: optimize ____napi_schedule() to avoid extra NET_RX_SOFTIRQEric Dumazet1-4/+18
____napi_schedule() adds a napi into current cpu softnet_data poll_list, then raises NET_RX_SOFTIRQ to make sure net_rx_action() will process it. Idea of this patch is to not raise NET_RX_SOFTIRQ when being called indirectly from net_rx_action(), because we can process poll_list from this point, without going to full softirq loop. This needs a change in net_rx_action() to make sure we restart its main loop if sd->poll_list was updated without NET_RX_SOFTIRQ being raised. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Xing <kernelxing@tencent.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: optimize napi_schedule_rps()Eric Dumazet1-3/+5
Based on initial patch from Jason Xing. Idea is to not raise NET_RX_SOFTIRQ from napi_schedule_rps() when we queued a packet into another cpu backlog. We can do this only in the context of us being called indirectly from net_rx_action(), to have the guarantee our rps_ipi_list will be processed before we exit from net_rx_action(). Link: https://lore.kernel.org/lkml/20230325152417.5403-1-kerneljasonxing@gmail.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Xing <kernelxing@tencent.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: add softnet_data.in_net_rx_actionEric Dumazet1-0/+4
We want to make two optimizations in napi_schedule_rps() and ____napi_schedule() which require to know if these helpers are called from net_rx_action(), instead of being called from other contexts. sd.in_net_rx_action is only read/written by the owning cpu. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: napi_schedule_rps() cleanupEric Dumazet1-6/+12
napi_schedule_rps() return value is ignored, remove it. Change the comment to clarify the intent. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-29net: dst: Switch to rcuref_t reference countingThomas Gleixner2-22/+6
Under high contention dst_entry::__refcnt becomes a significant bottleneck. atomic_inc_not_zero() is implemented with a cmpxchg() loop, which goes into high retry rates on contention. Switch the reference count to rcuref_t which results in a significant performance gain. Rename the reference count member to __rcuref to reflect the change. The gain depends on the micro-architecture and the number of concurrent operations and has been measured in the range of +25% to +130% with a localhost memtier/memcached benchmark which amplifies the problem massively. Running the memtier/memcached benchmark over a real (1Gb) network connection the conversion on top of the false sharing fix for struct dst_entry::__refcnt results in a total gain in the 2%-5% range over the upstream baseline. Reported-by: Wangyang Guo <wangyang.guo@intel.com> Reported-by: Arjan Van De Ven <arjan.van.de.ven@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230307125538.989175656@linutronix.de Link: https://lore.kernel.org/r/20230323102800.215027837@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-27dev_ioctl: fix a W=1 warningHeiner Kallweit1-0/+1
This fixes the following warning when compiled with GCC 12.2.0 and W=1. net/core/dev_ioctl.c:475: warning: Function parameter or member 'data' not described in 'dev_ioctl' Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-26bpf: Use bpf_mem_cache_alloc/free in bpf_local_storage_elemMartin KaFai Lau1-1/+1
This patch uses bpf_mem_alloc for the task and cgroup local storage that the bpf prog can easily get a hold of the storage owner's PTR_TO_BTF_ID. eg. bpf_get_current_task_btf() can be used in some of the kmalloc code path which will cause deadlock/recursion. bpf_mem_cache_alloc is deadlock free and will solve a legit use case in [1]. For sk storage, its batch creation benchmark shows a few percent regression when the sk create/destroy batch size is larger than 32. The sk creation/destruction happens much more often and depends on external traffic. Considering it is hypothetical to be able to cause deadlock with sk storage, it can cross the bridge to use bpf_mem_alloc till a legit (ie. useful) use case comes up. For inode storage, bpf_local_storage_destroy() is called before waiting for a rcu gp and its memory cannot be reused immediately. inode stays with kmalloc/kfree after the rcu [or tasks_trace] gp. A 'bool bpf_ma' argument is added to bpf_local_storage_map_alloc(). Only task and cgroup storage have 'bpf_ma == true' which means to use bpf_mem_cache_alloc/free(). This patch only changes selem to use bpf_mem_alloc for task and cgroup. The next patch will change the local_storage to use bpf_mem_alloc also for task and cgroup. Here is some more details on the changes: * memory allocation: After bpf_mem_cache_alloc(), the SDATA(selem)->data is zero-ed because bpf_mem_cache_alloc() could return a reused selem. It is to keep the existing bpf_map_kzalloc() behavior. Only SDATA(selem)->data is zero-ed. SDATA(selem)->data is the visible part to the bpf prog. No need to use zero_map_value() to do the zeroing because bpf_selem_free(..., reuse_now = true) ensures no bpf prog is using the selem before returning the selem through bpf_mem_cache_free(). For the internal fields of selem, they will be initialized when linking to the new smap and the new local_storage. When 'bpf_ma == false', nothing changes in this patch. It will stay with the bpf_map_kzalloc(). * memory free: The bpf_selem_free() and bpf_selem_free_rcu() are modified to handle the bpf_ma == true case. For the common selem free path where its owner is also being destroyed, the mem is freed in bpf_local_storage_destroy(), the owner (task and cgroup) has gone through a rcu gp. The memory can be reused immediately, so bpf_local_storage_destroy() will call bpf_selem_free(..., reuse_now = true) which will do bpf_mem_cache_free() for immediate reuse consideration. An exception is the delete elem code path. The delete elem code path is called from the helper bpf_*_storage_delete() and the syscall bpf_map_delete_elem(). This path is an unusual case for local storage because the common use case is to have the local storage staying with its owner life time so that the bpf prog and the user space does not have to monitor the owner's destruction. For the delete elem path, the selem cannot be reused immediately because there could be bpf prog using it. It will call bpf_selem_free(..., reuse_now = false) and it will wait for a rcu tasks trace gp before freeing the elem. The rcu callback is changed to do bpf_mem_cache_raw_free() instead of kfree(). When 'bpf_ma == false', it should be the same as before. __bpf_selem_free() is added to do the kfree_rcu and call_tasks_trace_rcu(). A few words on the 'reuse_now == true'. When 'reuse_now == true', it is still racing with bpf_local_storage_map_free which is under rcu protection, so it still needs to wait for a rcu gp instead of kfree(). Otherwise, the selem may be reused by slab for a totally different struct while the bpf_local_storage_map_free() is still using it (as a rcu reader). For the inode case, there may be other rcu readers also. In short, when bpf_ma == false and reuse_now == true => vanilla rcu. [1]: https://lore.kernel.org/bpf/20221118190109.1512674-1-namhyung@kernel.org/ Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230322215246.1675516-3-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-2/+8
Conflicts: drivers/net/ethernet/mellanox/mlx5/core/en_tc.c 6e9d51b1a5cb ("net/mlx5e: Initialize link speed to zero") 1bffcea42926 ("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 323fe43cf9ae ("net: phy: Improved PHY error reporting in state machine") 4203d84032e2 ("net: phy: Ensure state transitions are processed from phy_stop()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-24Merge tag 'for-netdev' of ↵Jakub Kicinski1-2/+8
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2023-03-23 We've added 8 non-merge commits during the last 13 day(s) which contain a total of 21 files changed, 238 insertions(+), 161 deletions(-). The main changes are: 1) Fix verification issues in some BPF programs due to their stack usage patterns, from Eduard Zingerman. 2) Fix to add missing overflow checks in xdp_umem_reg and return an error in such case, from Kal Conley. 3) Fix and undo poisoning of strlcpy in libbpf given it broke builds for libcs which provided the former like uClibc-ng, from Jesus Sanchez-Palencia. 4) Fix insufficient bpf_jit_limit default to avoid users running into hard to debug seccomp BPF errors, from Daniel Borkmann. 5) Fix driver return code when they don't support a bpf_xdp_metadata kfunc to make it unambiguous from other errors, from Jesper Dangaard Brouer. 6) Two BPF selftest fixes to address compilation errors from recent changes in kernel structures, from Alexei Starovoitov. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support bpf: Adjust insufficient default bpf_jit_limit xsk: Add missing overflow check in xdp_umem_reg selftests/bpf: Fix progs/test_deny_namespace.c issues. selftests/bpf: Fix progs/find_vma_fail1.c build error. libbpf: Revert poisoning of strlcpy selftests/bpf: Tests for uninitialized stack reads bpf: Allow reads from uninit stack ==================== Link: https://lore.kernel.org/r/20230323225221.6082-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-23net: do not use skb_mac_header() in qdisc_pkt_len_init()Eric Dumazet1-4/+4
We want to remove our use of skb_mac_header() in tx paths, eg remove skb_reset_mac_header() from __dev_queue_xmit(). Idea is that ndo_start_xmit() can get the mac header simply looking at skb->data. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-23net: Catch invalid index in XPS mappingNick Child1-0/+2
When setting the XPS value of a TX queue, warn the user once if the index of the queue is greater than the number of allocated TX queues. Previously, this scenario went uncaught. In the best case, it resulted in unnecessary allocations. In the worst case, it resulted in out-of-bounds memory references through calls to `netdev_get_tx_queue( dev, index)`. Therefore, it is important to inform the user but not worth returning an error and risk downing the netdevice. Signed-off-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com> Link: https://lore.kernel.org/r/20230321150725.127229-1-nnac123@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-23bpf: return long from bpf_map_ops funcsJP Kobryn2-7/+7
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 bdb7b79b4ce8. 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: bdb7b79b4ce8 ("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>
2023-03-22xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver supportJesper Dangaard Brouer1-2/+8
When driver doesn't implement a bpf_xdp_metadata kfunc the fallback implementation returns EOPNOTSUPP, which indicate device driver doesn't implement this kfunc. Currently many drivers also return EOPNOTSUPP when the hint isn't available, which is ambiguous from an API point of view. Instead change drivers to return ENODATA in these cases. There can be natural cases why a driver doesn't provide any hardware info for a specific hint, even on a frame to frame basis (e.g. PTP). Lets keep these cases as separate return codes. When describing the return values, adjust the function kernel-doc layout to get proper rendering for the return values. Fixes: ab46182d0dcb ("net/mlx4_en: Support RX XDP metadata") Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata") Fixes: 306531f0249f ("veth: Support RX XDP metadata") Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Link: https://lore.kernel.org/r/167940675120.2718408.8176058626864184420.stgit@firesoul Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-22net-zerocopy: Reduce compound page head accessXiaoyan Li1-3/+11
When compound pages are enabled, although the mm layer still returns an array of page pointers, a subset (or all) of them may have the same page head since a max 180kb skb can span 2 hugepages if it is on the boundary, be a mix of pages and 1 hugepage, or fit completely in a hugepage. Instead of referencing page head on all page pointers, use page length arithmetic to only call page head when referencing a known different page head to avoid touching a cold cacheline. Tested: See next patch with changes to tcp_mmap Correntess: On a pair of separate hosts as send with MSG_ZEROCOPY will force a copy on tx if using loopback alone, check that the SHA on the message sent is equivalent to checksum on the message received, since the current program already checks for the length. echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages ./tcp_mmap -s -z ./tcp_mmap -H $DADDR -z SHA256 is correct received 2 MB (100 % mmap'ed) in 0.005914 s, 2.83686 Gbit cpu usage user:0.001984 sys:0.000963, 1473.5 usec per MB, 10 c-switches Performance: Run neper between adjacent hosts with the same config tcp_stream -Z --skip-rx-copy -6 -T 20 -F 1000 --stime-use-proc --test-length=30 Before patch: stime_end=37.670000 After patch: stime_end=30.310000 Signed-off-by: Coco Li <lixiaoyan@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230321081202.2370275-1-lixiaoyan@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-22net-sysfs: display two backlog queue len separatelyJason Xing1-5/+13
Sometimes we need to know which one of backlog queue can be exactly long enough to cause some latency when debugging this part is needed. Thus, we can then separate the display of both. Signed-off-by: Jason Xing <kernelxing@tencent.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Link: https://lore.kernel.org/r/20230321015746.96994-1-kerneljasonxing@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-22tools: ynl: skip the explicit op array size when not neededJakub Kicinski1-1/+1
Jiri suggests it reads more naturally to skip the explicit array size when possible. When we export the symbol we want to make sure that the size is right but for statics its not needed. Link: https://lore.kernel.org/r/20230321044159.1031040-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-22neighbour: switch to standard rcu, instead of rcu_bhEric Dumazet2-38/+42
rcu_bh is no longer a win, especially for objects freed with standard call_rcu(). Switch neighbour code to no longer disable BH when not necessary. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-21net: skbuff: rename __pkt_vlan_present_offset to __mono_tc_offsetJakub Kicinski1-4/+4
vlan_present is gone since commit 354259fa73e2 ("net: remove skb->vlan_present") rename the offset field to what BPF is currently looking for in this byte - mono_delivery_time and tc_at_ingress. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20230321014115.997841-2-kuba@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-03-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-9/+23
net/wireless/nl80211.c b27f07c50a73 ("wifi: nl80211: fix puncturing bitmap policy") cbbaf2bb829b ("wifi: nl80211: add a command to enable/disable HW timestamping") https://lore.kernel.org/all/20230314105421.3608efae@canb.auug.org.au tools/testing/selftests/net/Makefile 62199e3f1658 ("selftests: net: Add VXLAN MDB test") 13715acf8ab5 ("selftest: Add test for bind() conflicts.") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-17rtnetlink: bridge: mcast: Relax group address validation in common codeIdo Schimmel1-2/+3
In the upcoming VXLAN MDB implementation, the 0.0.0.0 and :: MDB entries will act as catchall entries for unregistered IP multicast traffic in a similar fashion to the 00:00:00:00:00:00 VXLAN FDB entry that is used to transmit BUM traffic. In deployments where inter-subnet multicast forwarding is used, not all the VTEPs in a tenant domain are members in all the broadcast domains. It is therefore advantageous to transmit BULL (broadcast, unknown unicast and link-local multicast) and unregistered IP multicast traffic on different tunnels. If the same tunnel was used, a VTEP only interested in IP multicast traffic would also pull all the BULL traffic and drop it as it is not a member in the originating broadcast domain [1]. Prepare for this change by allowing the 0.0.0.0 group address in the common rtnetlink MDB code and forbid it in the bridge driver. A similar change is not needed for IPv6 because the common code only validates that the group address is not the all-nodes address. [1] https://datatracker.ietf.org/doc/html/draft-ietf-bess-evpn-irb-mcast#section-2.6 Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-17rtnetlink: bridge: mcast: Move MDB handlers out of bridge driverIdo Schimmel1-0/+217
Currently, the bridge driver registers handlers for MDB netlink messages, making it impossible for other drivers to implement MDB support. As a preparation for VXLAN MDB support, move the MDB handlers out of the bridge driver to the core rtnetlink code. The rtnetlink code will call into individual drivers by invoking their previously added MDB net device operations. Note that while the diffstat is large, the change is mechanical. It moves code out of the bridge driver to rtnetlink code. Also note that a similar change was made in 2012 with commit 77162022ab26 ("net: add generic PF_BRIDGE:RTM_ FDB hooks") that moved FDB handlers out of the bridge driver to the core rtnetlink code. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-17net: xdp: don't call notifiers during driver initJakub Kicinski1-1/+3
Drivers will commonly perform feature setting during init, if they use the xdp_set_features_flag() helper they'll likely run into an ASSERT_RTNL() inside call_netdevice_notifiers_info(). Don't call the notifier until the device is actually registered. Nothing should be tracking the device until its registered and after its unregistration has started. Fixes: 4d5ab0ad964d ("net/mlx5e: take into account device reconfiguration for xdp_features flag") Link: https://lore.kernel.org/r/20230316220234.598091-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-17ynl: broaden the license even moreJakub Kicinski2-2/+2
I relicensed Netlink spec code to GPL-2.0 OR BSD-3-Clause but we still put a slightly different license on the uAPI header than the rest of the code. Use the Linux-syscall-note on all the specs and all generated code. It's moot for kernel code, but should not hurt. This way the licenses match everywhere. Cc: Chuck Lever <chuck.lever@oracle.com> Fixes: 37d9df224d1e ("ynl: re-license uniformly under GPL-2.0 OR BSD-3-Clause") Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15neighbour: annotate lockless accesses to n->nud_stateEric Dumazet2-16/+16
We have many lockless accesses to n->nud_state. Before adding another one in the following patch, add annotations to readers and writers. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15xdp: remove unused {__,}xdp_release_frame()Alexander Lobakin1-15/+0
__xdp_build_skb_from_frame() was the last user of {__,}xdp_release_frame(), which detaches pages from the page_pool. All the consumers now recycle Page Pool skbs and page, except mlx5, stmmac and tsnep drivers, which use page_pool_release_page() directly (might change one day). It's safe to assume this functionality is not needed anymore and can be removed (in favor of recycling). Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20230313215553.1045175-5-aleksander.lobakin@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-15xdp: recycle Page Pool backed skbs built from XDP framesAlexander Lobakin1-2/+2
__xdp_build_skb_from_frame() state(d): /* Until page_pool get SKB return path, release DMA here */ Page Pool got skb pages recycling in April 2021, but missed this function. xdp_release_frame() is relevant only for Page Pool backed frames and it detaches the page from the corresponding page_pool in order to make it freeable via page_frag_free(). It can instead just mark the output skb as eligible for recycling if the frame is backed by a pp. No change for other memory model types (the same condition check as before). cpumap redirect and veth on Page Pool drivers now become zero-alloc (or almost). Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20230313215553.1045175-4-aleksander.lobakin@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-11xdp: add xdp_set_features_flag utility routineLorenzo Bianconi1-7/+19
Introduce xdp_set_features_flag utility routine in order to update dynamically xdp_features according to the dynamic hw configuration via ethtool (e.g. changing number of hw rx/tx queues). Add xdp_clear_features_flag() in order to clear all xdp_feature flag. Reviewed-by: Shay Agroskin <shayagr@amazon.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-11skbuff: Add likely to skb pointer in build_skb()Gal Pressman1-1/+1
Similarly to napi_build_skb(), it is likely the skb allocation in build_skb() succeeded. frag_size != 0 is also likely, as stated in __build_skb_around(). Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-11skbuff: Replace open-coded skb_propagate_pfmemalloc()sGal Pressman1-4/+2
Use skb_propagate_pfmemalloc() in build_skb()/build_skb_around() instead of open-coding it. Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-10bpf: Add bpf_selem_free()Martin KaFai Lau1-1/+1
This patch refactors the selem freeing logic into bpf_selem_free(). It is a preparation work for a later patch using bpf_mem_cache_alloc/free. The other kfree(selem) cases are also changed to bpf_selem_free(..., reuse_now = true). Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230308065936.1550103-10-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-10bpf: Repurpose use_trace_rcu to reuse_now in bpf_local_storageMartin KaFai Lau1-1/+1
This patch re-purpose the use_trace_rcu to mean if the freed memory can be reused immediately or not. The use_trace_rcu is renamed to reuse_now. Other than the boolean test is reversed, it should be a no-op. The following explains the reason for the rename and how it will be used in a later patch. In a later patch, bpf_mem_cache_alloc/free will be used in the bpf_local_storage. The bpf mem allocator will reuse the freed memory immediately. Some of the free paths in bpf_local_storage does not support memory to be reused immediately. These paths are the "delete" elem cases from the bpf_*_storage_delete() helper and the map_delete_elem() syscall. Note that "delete" elem before the owner's (sk/task/cgrp/inode) lifetime ended is not the common usage for the local storage. The common free path, bpf_local_storage_destroy(), can reuse the memory immediately. This common path means the storage stays with its owner until the owner is destroyed. The above mentioned "delete" elem paths that cannot reuse immediately always has the 'use_trace_rcu == true'. The cases that is safe for immediate reuse always have 'use_trace_rcu == false'. Instead of adding another arg in a later patch, this patch re-purpose this arg to reuse_now and have the test logic reversed. In a later patch, 'reuse_now == true' will free to the bpf_mem_cache_free() where the memory can be reused immediately. 'reuse_now == false' will go through the call_rcu_tasks_trace(). Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230308065936.1550103-7-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-10bpf: Refactor codes into bpf_local_storage_destroyMartin KaFai Lau1-7/+1
This patch first renames bpf_local_storage_unlink_nolock to bpf_local_storage_destroy(). It better reflects that it is only used when the storage's owner (sk/task/cgrp/inode) is being kfree(). All bpf_local_storage_destroy's caller is taking the spin lock and then free the storage. This patch also moves these two steps into the bpf_local_storage_destroy. This is a preparation work for a later patch that uses bpf_mem_cache_alloc/free in the bpf_local_storage. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230308065936.1550103-3-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-10neighbour: delete neigh_lookup_nodev as not usedLeon Romanovsky1-31/+0
neigh_lookup_nodev isn't used in the kernel after removal of DECnet. So let's remove it. Fixes: 1202cdd66531 ("Remove DECnet support from kernel") Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/eb5656200d7964b2d177a36b77efa3c597d6d72d.1678267343.git.leonro@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski4-11/+27
Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") d56b0c461d19 ("bpf, docs: Fix link to netdev-FAQ target") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-09Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski2-0/+21
Andrii Nakryiko says: ==================== pull-request: bpf-next 2023-03-08 We've added 23 non-merge commits during the last 2 day(s) which contain a total of 28 files changed, 414 insertions(+), 104 deletions(-). The main changes are: 1) Add more precise memory usage reporting for all BPF map types, from Yafang Shao. 2) Add ARM32 USDT support to libbpf, from Puranjay Mohan. 3) Fix BTF_ID_LIST size causing problems in !CONFIG_DEBUG_INFO_BTF, from Nathan Chancellor. 4) IMA selftests fix, from Roberto Sassu. 5) libbpf fix in APK support code, from Daniel Müller. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (23 commits) selftests/bpf: Fix IMA test libbpf: USDT arm arg parsing support libbpf: Refactor parse_usdt_arg() to re-use code libbpf: Fix theoretical u32 underflow in find_cd() function bpf: enforce all maps having memory usage callback bpf: offload map memory usage bpf, net: xskmap memory usage bpf, net: sock_map memory usage bpf, net: bpf_local_storage memory usage bpf: local_storage memory usage bpf: bpf_struct_ops memory usage bpf: queue_stack_maps memory usage bpf: devmap memory usage bpf: cpumap memory usage bpf: bloom_filter memory usage bpf: ringbuf memory usage bpf: reuseport_array memory usage bpf: stackmap memory usage bpf: arraymap memory usage bpf: hashtab memory usage ... ==================== Link: https://lore.kernel.org/r/20230308193533.1671597-1-andrii@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-08net: remove enum skb_free_reasonEric Dumazet1-11/+9
enum skb_drop_reason is more generic, we can adopt it instead. Provide dev_kfree_skb_irq_reason() and dev_kfree_skb_any_reason(). This means drivers can use more precise drop reasons if they want to. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Link: https://lore.kernel.org/r/20230306204313.10492-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-08ynl: re-license uniformly under GPL-2.0 OR BSD-3-ClauseJakub Kicinski2-2/+2
I was intending to make all the Netlink Spec code BSD-3-Clause to ease the adoption but it appears that: - I fumbled the uAPI and used "GPL WITH uAPI note" there - it gives people pause as they expect GPL in the kernel As suggested by Chuck re-license under dual. This gives us benefit of full BSD freedom while fulfilling the broad "kernel is under GPL" expectations. Link: https://lore.kernel.org/all/20230304120108.05dd44c5@kernel.org/ Link: https://lore.kernel.org/r/20230306200457.3903854-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-07bpf, net: sock_map memory usageYafang Shao1-0/+20
sockmap and sockhash don't have something in common in allocation, so let's introduce different helpers to calculate their memory usage. The reuslt as follows, - before 28: sockmap name count_map flags 0x0 key 4B value 4B max_entries 65536 memlock 524288B 29: sockhash name count_map flags 0x0 key 4B value 4B max_entries 65536 memlock 524288B - after 28: sockmap name count_map flags 0x0 key 4B value 4B max_entries 65536 memlock 524608B 29: sockhash name count_map flags 0x0 <<<< no updated elements key 4B value 4B max_entries 65536 memlock 1048896B Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20230305124615.12358-16-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-07bpf, net: bpf_local_storage memory usageYafang Shao1-0/+1
A new helper is introduced into bpf_local_storage map to calculate the memory usage. This helper is also used by other maps like bpf_cgrp_storage, bpf_inode_storage, bpf_task_storage and etc. Note that currently the dynamically allocated storage elements are not counted in the usage, since it will take extra runtime overhead in the elements update or delete path. So let's put it aside now, and implement it in the future when someone really need it. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20230305124615.12358-15-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-07Merge tag 'for-netdev' of ↵Jakub Kicinski1-45/+148
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2023-03-06 We've added 85 non-merge commits during the last 13 day(s) which contain a total of 131 files changed, 7102 insertions(+), 1792 deletions(-). The main changes are: 1) Add skb and XDP typed dynptrs which allow BPF programs for more ergonomic and less brittle iteration through data and variable-sized accesses, from Joanne Koong. 2) Bigger batch of BPF verifier improvements to prepare for upcoming BPF open-coded iterators allowing for less restrictive looping capabilities, from Andrii Nakryiko. 3) Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF programs to NULL-check before passing such pointers into kfunc, from Alexei Starovoitov. 4) Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in local storage maps, from Kumar Kartikeya Dwivedi. 5) Add BPF verifier support for ST instructions in convert_ctx_access() which will help new -mcpu=v4 clang flag to start emitting them, from Eduard Zingerman. 6) Make uprobe attachment Android APK aware by supporting attachment to functions inside ELF objects contained in APKs via function names, from Daniel Müller. 7) Add a new flag BPF_F_TIMER_ABS flag for bpf_timer_start() helper to start the timer with absolute expiration value instead of relative one, from Tero Kristo. 8) Add a new kfunc bpf_cgroup_from_id() to look up cgroups via id, from Tejun Heo. 9) Extend libbpf to support users manually attaching kprobes/uprobes in the legacy/perf/link mode, from Menglong Dong. 10) Implement workarounds in the mips BPF JIT for DADDI/R4000, from Jiaxun Yang. 11) Enable mixing bpf2bpf and tailcalls for the loongarch BPF JIT, from Hengqi Chen. 12) Extend BPF instruction set doc with describing the encoding of BPF instructions in terms of how bytes are stored under big/little endian, from Jose E. Marchesi. 13) Follow-up to enable kfunc support for riscv BPF JIT, from Pu Lehui. 14) Fix bpf_xdp_query() backwards compatibility on old kernels, from Yonghong Song. 15) Fix BPF selftest cross compilation with CLANG_CROSS_FLAGS, from Florent Revest. 16) Improve bpf_cpumask_ma to only allocate one bpf_mem_cache, from Hou Tao. 17) Fix BPF verifier's check_subprogs to not unnecessarily mark a subprogram with has_tail_call, from Ilya Leoshkevich. 18) Fix arm syscall regs spec in libbpf's bpf_tracing.h, from Puranjay Mohan. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (85 commits) selftests/bpf: Add test for legacy/perf kprobe/uprobe attach mode selftests/bpf: Split test_attach_probe into multi subtests libbpf: Add support to set kprobe/uprobe attach mode tools/resolve_btfids: Add /libsubcmd to .gitignore bpf: add support for fixed-size memory pointer returns for kfuncs bpf: generalize dynptr_get_spi to be usable for iters bpf: mark PTR_TO_MEM as non-null register type bpf: move kfunc_call_arg_meta higher in the file bpf: ensure that r0 is marked scratched after any function call bpf: fix visit_insn()'s detection of BPF_FUNC_timer_set_callback helper bpf: clean up visit_insn()'s instruction processing selftests/bpf: adjust log_fixup's buffer size for proper truncation bpf: honor env->test_state_freq flag in is_state_visited() selftests/bpf: enhance align selftest's expected log matching bpf: improve regsafe() checks for PTR_TO_{MEM,BUF,TP_BUFFER} bpf: improve stack slot state printing selftests/bpf: Disassembler tests for verifier.c:convert_ctx_access() selftests/bpf: test if pointer type is tracked for BPF_ST_MEM bpf: allow ctx writes using BPF_ST_MEM instruction bpf: Use separate RCU callbacks for freeing selem ... ==================== Link: https://lore.kernel.org/r/20230307004346.27578-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-04bpf: allow ctx writes using BPF_ST_MEM instructionEduard Zingerman1-35/+44
Lift verifier restriction to use BPF_ST_MEM instructions to write to context data structures. This requires the following changes: - verifier.c:do_check() for BPF_ST updated to: - no longer forbid writes to registers of type PTR_TO_CTX; - track dst_reg type in the env->insn_aux_data[...].ptr_type field (same way it is done for BPF_STX and BPF_LDX instructions). - verifier.c:convert_ctx_access() and various callbacks invoked by it are updated to handled BPF_ST instruction alongside BPF_STX. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20230304011247.566040-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-03bpf: Make bpf_get_current_[ancestor_]cgroup_id() available for all program typesTejun Heo1-6/+0
These helpers are safe to call from any context and there's no reason to restrict access to them. Remove them from bpf_trace and filter lists and add to bpf_base_func_proto() under perfmon_capable(). v2: After consulting with Andrii, relocated in bpf_base_func_proto() so that they require bpf_capable() but not perfomon_capable() as it doesn't read from or affect others on the system. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/ZAD8QyoszMZiTzBY@slm.duckdns.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-02net: use indirect calls helpers for sk_exit_memory_pressure()Brian Vazquez1-1/+2
Florian reported a regression and sent a patch with the following changelog: <quote> There is a noticeable tcp performance regression (loopback or cross-netns), seen with iperf3 -Z (sendfile mode) when generic retpolines are needed. With SK_RECLAIM_THRESHOLD checks gone number of calls to enter/leave memory pressure happen much more often. For TCP indirect calls are used. We can't remove the if-set-return short-circuit check in tcp_enter_memory_pressure because there are callers other than sk_enter_memory_pressure. Doing a check in the sk wrapper too reduces the indirect calls enough to recover some performance. Before, 0.00-60.00 sec 322 GBytes 46.1 Gbits/sec receiver After: 0.00-60.04 sec 359 GBytes 51.4 Gbits/sec receiver "iperf3 -c $peer -t 60 -Z -f g", connected via veth in another netns. </quote> It seems we forgot to upstream this indirect call mitigation we had for years, lets do this instead. [edumazet] - It seems we forgot to upstream this indirect call mitigation we had for years, let's do this instead. - Changed to INDIRECT_CALL_INET_1() to avoid bots reports. Fixes: 4890b686f408 ("net: keep sk->sk_forward_alloc as small as possible") Reported-by: Florian Westphal <fw@strlen.de> Link: https://lore.kernel.org/netdev/20230227152741.4a53634b@kernel.org/T/ Signed-off-by: Brian Vazquez <brianvv@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230301133247.2346111-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-01bpf: Add bpf_dynptr_slice and bpf_dynptr_slice_rdwrJoanne Koong1-3/+3
Two new kfuncs are added, bpf_dynptr_slice and bpf_dynptr_slice_rdwr. The user must pass in a buffer to store the contents of the data slice if a direct pointer to the data cannot be obtained. For skb and xdp type dynptrs, these two APIs are the only way to obtain a data slice. However, for other types of dynptrs, there is no difference between bpf_dynptr_slice(_rdwr) and bpf_dynptr_data. For skb type dynptrs, the data is copied into the user provided buffer if any of the data is not in the linear portion of the skb. For xdp type dynptrs, the data is copied into the user provided buffer if the data is between xdp frags. If the skb is cloned and a call to bpf_dynptr_data_rdwr is made, then the skb will be uncloned (see bpf_unclone_prologue()). Please note that any bpf_dynptr_write() automatically invalidates any prior data slices of the skb dynptr. This is because the skb may be cloned or may need to pull its paged buffer into the head. As such, any bpf_dynptr_write() will automatically have its prior data slices invalidated, even if the write is to data in the skb head of an uncloned skb. Please note as well that any other helper calls that change the underlying packet buffer (eg bpf_skb_pull_data()) invalidates any data slices of the skb dynptr as well, for the same reasons. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://lore.kernel.org/r/20230301154953.641654-10-joannelkoong@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01bpf: Add xdp dynptrsJoanne Koong1-2/+35
Add xdp dynptrs, which are dynptrs whose underlying pointer points to a xdp_buff. The dynptr acts on xdp data. xdp dynptrs have two main benefits. One is that they allow operations on sizes that are not statically known at compile-time (eg variable-sized accesses). Another is that parsing the packet data through dynptrs (instead of through direct access of xdp->data and xdp->data_end) can be more ergonomic and less brittle (eg does not need manual if checking for being within bounds of data_end). For reads and writes on the dynptr, this includes reading/writing from/to and across fragments. Data slices through the bpf_dynptr_data API are not supported; instead bpf_dynptr_slice() and bpf_dynptr_slice_rdwr() should be used. For examples of how xdp dynptrs can be used, please see the attached selftests. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://lore.kernel.org/r/20230301154953.641654-9-joannelkoong@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01bpf: Add skb dynptrsJoanne Koong1-0/+67
Add skb dynptrs, which are dynptrs whose underlying pointer points to a skb. The dynptr acts on skb data. skb dynptrs have two main benefits. One is that they allow operations on sizes that are not statically known at compile-time (eg variable-sized accesses). Another is that parsing the packet data through dynptrs (instead of through direct access of skb->data and skb->data_end) can be more ergonomic and less brittle (eg does not need manual if checking for being within bounds of data_end). For bpf prog types that don't support writes on skb data, the dynptr is read-only (bpf_dynptr_write() will return an error) For reads and writes through the bpf_dynptr_read() and bpf_dynptr_write() interfaces, reading and writing from/to data in the head as well as from/to non-linear paged buffers is supported. Data slices through the bpf_dynptr_data API are not supported; instead bpf_dynptr_slice() and bpf_dynptr_slice_rdwr() (added in subsequent commit) should be used. For examples of how skb dynptrs can be used, please see the attached selftests. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Link: https://lore.kernel.org/r/20230301154953.641654-8-joannelkoong@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01net: avoid skb end_offset change in __skb_unclone_keeptruesize()Eric Dumazet1-8/+23
Once initial skb->head has been allocated from skb_small_head_cache, we need to make sure to use the same strategy whenever skb->head has to be re-allocated, as found by syzbot [1] This means kmalloc_reserve() can not fallback from using skb_small_head_cache to generic (power-of-two) kmem caches. It seems that we probably want to rework things in the future, to partially revert following patch, because we no longer use ksize() for skb allocated in TX path. 2b88cba55883 ("net: preserve skb_end_offset() in skb_unclone_keeptruesize()") Ideally, TCP stack should never put payload in skb->head, this effort has to be completed. In the mean time, add a sanity check. [1] BUG: KASAN: invalid-free in slab_free mm/slub.c:3787 [inline] BUG: KASAN: invalid-free in kmem_cache_free+0xee/0x5c0 mm/slub.c:3809 Free of addr ffff88806cdee800 by task syz-executor239/5189 CPU: 0 PID: 5189 Comm: syz-executor239 Not tainted 6.2.0-rc8-syzkaller-02400-gd1fabc68f8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x45d mm/kasan/report.c:417 kasan_report_invalid_free+0x9b/0x1b0 mm/kasan/report.c:482 ____kasan_slab_free+0x1a5/0x1c0 mm/kasan/common.c:216 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] kmem_cache_free+0xee/0x5c0 mm/slub.c:3809 skb_kfree_head net/core/skbuff.c:857 [inline] skb_kfree_head net/core/skbuff.c:853 [inline] skb_free_head+0x16f/0x1a0 net/core/skbuff.c:872 skb_release_data+0x57a/0x820 net/core/skbuff.c:901 skb_release_all net/core/skbuff.c:966 [inline] __kfree_skb+0x4f/0x70 net/core/skbuff.c:980 tcp_wmem_free_skb include/net/tcp.h:302 [inline] tcp_rtx_queue_purge net/ipv4/tcp.c:3061 [inline] tcp_write_queue_purge+0x617/0xcf0 net/ipv4/tcp.c:3074 tcp_v4_destroy_sock+0x125/0x810 net/ipv4/tcp_ipv4.c:2302 inet_csk_destroy_sock+0x19a/0x440 net/ipv4/inet_connection_sock.c:1195 __tcp_close+0xb96/0xf50 net/ipv4/tcp.c:3021 tcp_close+0x2d/0xc0 net/ipv4/tcp.c:3033 inet_release+0x132/0x270 net/ipv4/af_inet.c:426 __sock_release+0xcd/0x280 net/socket.c:651 sock_close+0x1c/0x20 net/socket.c:1393 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2511f546c3 Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 RSP: 002b:00007ffef0103d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f2511f546c3 RDX: 0000000000000978 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000003434 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffef0103d6c R13: 00007ffef0103d80 R14: 00007ffef0103dc0 R15: 0000000000000003 </TASK> Allocated by task 5189: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa5/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:968 [inline] __kmalloc_node_track_caller+0x5b/0xc0 mm/slab_common.c:988 kmalloc_reserve+0xf1/0x230 net/core/skbuff.c:539 pskb_expand_head+0x237/0x1160 net/core/skbuff.c:1995 __skb_unclone_keeptruesize+0x93/0x220 net/core/skbuff.c:2094 skb_unclone_keeptruesize include/linux/skbuff.h:1910 [inline] skb_prepare_for_shift net/core/skbuff.c:3804 [inline] skb_shift+0xef8/0x1e20 net/core/skbuff.c:3877 tcp_skb_shift net/ipv4/tcp_input.c:1538 [inline] tcp_shift_skb_data net/ipv4/tcp_input.c:1646 [inline] tcp_sacktag_walk+0x93b/0x18a0 net/ipv4/tcp_input.c:1713 tcp_sacktag_write_queue+0x1599/0x31d0 net/ipv4/tcp_input.c:1974 tcp_ack+0x2e9f/0x5a10 net/ipv4/tcp_input.c:3847 tcp_rcv_established+0x667/0x2230 net/ipv4/tcp_input.c:6006 tcp_v4_do_rcv+0x670/0x9b0 net/ipv4/tcp_ipv4.c:1721 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x133/0x3b0 net/core/sock.c:2921 release_sock+0x58/0x1b0 net/core/sock.c:3488 tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1485 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 sock_write_iter+0x295/0x3d0 net/socket.c:1136 call_write_iter include/linux/fs.h:2189 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9ed/0xdd0 fs/read_write.c:584 ksys_write+0x1ec/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88806cdee800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of 1024-byte region [ffff88806cdee800, ffff88806cdeec00) The buggy address belongs to the physical page: page:ffffea0001b37a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6cde8 head:ffffea0001b37a00 order:3 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012441dc0 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1f2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_MEMALLOC|__GFP_HARDWALL), pid 75, tgid 75 (kworker/u4:4), ts 96369578780, free_ts 26734162530 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2287 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x1a4/0x430 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:988 kmalloc_reserve+0xf1/0x230 net/core/skbuff.c:539 __alloc_skb+0x129/0x330 net/core/skbuff.c:608 __netdev_alloc_skb+0x74/0x410 net/core/skbuff.c:672 __netdev_alloc_skb_ip_align include/linux/skbuff.h:3203 [inline] netdev_alloc_skb_ip_align include/linux/skbuff.h:3213 [inline] batadv_iv_ogm_aggregate_new+0x106/0x4e0 net/batman-adv/bat_iv_ogm.c:558 batadv_iv_ogm_queue_add net/batman-adv/bat_iv_ogm.c:670 [inline] batadv_iv_ogm_schedule_buff+0xe6b/0x1450 net/batman-adv/bat_iv_ogm.c:849 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x744/0x910 net/batman-adv/bat_iv_ogm.c:1712 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare+0x66a/0xc20 mm/page_alloc.c:1496 free_unref_page_prepare mm/page_alloc.c:3369 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3464 free_contig_range+0xb5/0x180 mm/page_alloc.c:9488 destroy_args+0xa8/0x64c mm/debug_vm_pgtable.c:998 debug_vm_pgtable+0x28de/0x296f mm/debug_vm_pgtable.c:1318 do_one_initcall+0x141/0x790 init/main.c:1306 do_initcall_level init/main.c:1379 [inline] do_initcalls init/main.c:1395 [inline] do_basic_setup init/main.c:1414 [inline] kernel_init_freeable+0x6f9/0x782 init/main.c:1634 kernel_init+0x1e/0x1d0 init/main.c:1522 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Memory state around the buggy address: ffff88806cdee700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806cdee780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806cdee800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88806cdee880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Fixes: bf9f1baa279f ("net: add dedicated kmem_cache for typical/small skb->head") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>