- 09 Oct, 2020 7 commits
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Moshe Shemesh authored
Add reload limit to demand restrictions on reload actions. Reload limits supported: no_reset: No reset allowed, no down time allowed, no link flap and no configuration is lost. By default reload limit is unspecified and so no constraints on reload actions are required. Some combinations of action and limit are invalid. For example, driver can not reinitialize its entities without any downtime. The no_reset reload limit will have usecase in this patchset to implement restricted fw_activate on mlx5. Have the uapi parameter of reload limit ready for future support of multiselection. Signed-off-by:Moshe Shemesh <moshe@mellanox.com> Reviewed-by:
Jiri Pirko <jiri@nvidia.com> Signed-off-by:
Jakub Kicinski <kuba@kernel.org>
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Moshe Shemesh authored
Add devlink reload action to allow the user to request a specific reload action. The action parameter is optional, if not specified then devlink driver re-init action is used (backward compatible). Note that when required to do firmware activation some drivers may need to reload the driver. On the other hand some drivers may need to reset the firmware to reinitialize the driver entities. Therefore, the devlink reload command returns the actions which were actually performed. Reload actions supported are: driver_reinit: driver entities re-initialization, applying devlink-param and devlink-resource values. fw_activate: firmware activate. command examples: $devlink dev reload pci/0000:82:00.0 action driver_reinit reload_actions_performed: driver_reinit $devlink dev reload pci/0000:82:00.0 action fw_activate reload_actions_performed: driver_reinit fw_activate Signed-off-by:Jacob Keller <jacob.e.keller@intel.com> Reviewed-by:
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Moshe Shemesh authored
Change devlink_reload_supported() function to get devlink_ops pointer param instead of devlink pointer param. This change will be used in the next patch to check if devlink reload is supported before devlink instance is allocated. Signed-off-by:
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Eric Dumazet authored
kmalloc() of sufficiently big portion of memory is cache-aligned in regular conditions. If some debugging options are used, there is no reason qdisc structures would need 64-byte alignment if most other kernel structures are not aligned. This get rid of QDISC_ALIGN and QDISC_ALIGNTO. Addition of privdata field will help implementing the reverse of qdisc_priv() and documents where the private data is. Signed-off-by:
Eric Dumazet <edumazet@google.com> Cc: Allen Pais <allen.lkml@gmail.com> Acked-by:
Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by:
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Matthieu Baerts authored
In case of errors, this message was printed: (...) balanced bwidth with unbalanced delay 5233 max 5005 [ fail ] client exit code 0, server 0 \nnetns ns3-0-EwnkPH socket stat for 10003: (...) Obviously, the idea was to add a new line before the socket stat and not print "\nnetns". The commit 8b974778 ("selftests: mptcp: interpret \n as a new line") is very similar to this one. But the modification in simult_flows.sh was missed because this commit above was done in parallel to one here below. Fixes: 1a418cb8 ("mptcp: simult flow self-tests") Signed-off-by:
Matthieu Baerts <matthieu.baerts@tessares.net> Acked-by:
Paolo Abeni <pabeni@redhat.com> Signed-off-by:
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Vladimir Oltean authored
Without these definitions, the driver will crash in: mscc_ocelot_probe -> ocelot_init -> ocelot_vcap_init -> __ocelot_target_read_ix I missed this because I did not have the VSC7514 hardware to test, only the VSC9959 and VSC9953, and the probing part is different. Fixes: e3aea296 ("net: mscc: ocelot: add definitions for VCAP ES0 keys, actions and target") Fixes: a61e365d ("net: mscc: ocelot: add definitions for VCAP IS1 keys, actions and target") Reported-by:Divya Koppera <Divya.Koppera@microchip.com> Signed-off-by:
Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by:
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Paolo Abeni authored
If recvmsg() and the workqueue race to dequeue the data pending on some subflow, the current mapping for such subflow covers several skbs and some of them have not reached yet the received, either the worker or recvmsg() can find a subflow with the data_avail flag set - since the current mapping is valid and in sequence - but no skbs in the receive queue - since the other entity just processed them. The above will lead to an unbounded loop in __mptcp_move_skbs() and a subsequent hang of any task trying to acquiring the msk socket lock. This change addresses the issue stopping the __mptcp_move_skbs() loop as soon as we detect the above race (empty receive queue with data_avail set). Reported-and-tested-by: syzbot+fcf8ca5817d6e92c6567@syzkaller.appspotmail.com Fixes: ab174ad8 ("mptcp: move ooo skbs into msk out of order queue.") Signed-off-by:
Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by:
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- 08 Oct, 2020 23 commits
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Allen Pais authored
In preparation for unconditionally passing the struct tasklet_struct pointer to all tasklet callbacks, switch to using the new tasklet_setup() and from_tasklet() to pass the tasklet pointer explicitly. Signed-off-by:
Romain Perier <romain.perier@gmail.com> Signed-off-by:
Allen Pais <apais@linux.microsoft.com> Signed-off-by:
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Johannes Berg authored
This accidentally got wired up to the *get* policy instead of the *set* policy, causing operations to be rejected. Fix it by wiring up the correct policy instead. Fixes: 5028588b ("ethtool: wire up set policies to ops") Reported-by:
Leon Romanovsky <leon@kernel.org> Signed-off-by:
Johannes Berg <johannes.berg@intel.com> Tested-by:
Leon Romanovsky <leonro@nvidia.com> Reviewed-by:
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Johannes Berg authored
The ETHTOOL_A_STRSET_COUNTS_ONLY flag attribute was previously not allowed to be used, but now due to the policy size reduction we would access the tb[] array out of bounds since we tried to check for the attribute despite it not being accepted. Fix both issues by adding it correctly to the appropriate policy. Fixes: ff419afa ("ethtool: trim policy tables") Fixes: 71921690 ("ethtool: provide string sets with STRSET_GET request") Reported-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski authored
Small conflict around locking in rxrpc_process_event() - channel_lock moved to bundle in next, while state lock needs _bh() from net. Signed-off-by: -
git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds authored
Pull vhost fixes from Michael Tsirkin: "Some last minute vhost,vdpa fixes. The last two of them haven't been in next but they do seem kind of obvious, very small and safe, fix bugs reported in the field, and they are both in a new mlx5 vdpa driver, so it's not like we can introduce regressions" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vdpa/mlx5: Fix dependency on MLX5_CORE vdpa/mlx5: should keep avail_index despite device status vhost-vdpa: fix page pinning leakage in error path vhost-vdpa: fix vhost_vdpa_map() on error condition vhost: Don't call log_access_ok() when using IOTLB vhost: Use vhost_get_used_size() in vhost_vring_set_addr() vhost: Don't call access_ok() when using IOTLB vhost vdpa: fix vhost_vdpa_open error handling
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds authored
Pull networking fixes from Jakub Kicinski: "One more set of fixes from the networking tree: - add missing input validation in nl80211_del_key(), preventing out-of-bounds access - last minute fix / improvement of a MRP netlink (uAPI) interface introduced in 5.9 (current) release - fix "unresolved symbol" build error under CONFIG_NET w/o CONFIG_INET due to missing tcp_timewait_sock and inet_timewait_sock BTF. - fix 32 bit sub-register bounds tracking in the bpf verifier for OR case - tcp: fix receive window update in tcp_add_backlog() - openvswitch: handle DNAT tuple collision in conntrack-related code - r8169: wait for potential PHY reset to finish after applying a FW file, avoiding unexpected PHY behaviour and failures later on - mscc: fix tail dropping watermarks for Ocelot switches - avoid use-after-free in macsec code after a call to the GRO layer - avoid use-after-free in sctp error paths - add a device id for Cellient MPL200 WWAN card - rxrpc fixes: - fix the xdr encoding of the contents read from an rxrpc key - fix a BUG() for a unsupported encoding type. - fix missing _bh lock annotations. - fix acceptance handling for an incoming call where the incoming call is encrypted. - the server token keyring isn't network namespaced - it belongs to the server, so there's no need. Namespacing it means that request_key() fails to find it. - fix a leak of the server keyring" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (21 commits) net: usb: qmi_wwan: add Cellient MPL200 card macsec: avoid use-after-free in macsec_handle_frame() r8169: consider that PHY reset may still be in progress after applying firmware openvswitch: handle DNAT tuple collision sctp: fix sctp_auth_init_hmacs() error path bridge: Netlink interface fix. net: wireless: nl80211: fix out-of-bounds access in nl80211_del_key() bpf: Fix scalar32_min_max_or bounds tracking tcp: fix receive window update in tcp_add_backlog() net: usb: rtl8150: set random MAC address when set_ethernet_addr() fails mptcp: more DATA FIN fixes net: mscc: ocelot: warn when encoding an out-of-bounds watermark value net: mscc: ocelot: divide watermark value by 60 when writing to SYS_ATOP net: qrtr: ns: Fix the incorrect usage of rcu_read_lock() rxrpc: Fix server keyring leak rxrpc: The server keyring isn't network-namespaced rxrpc: Fix accept on a connection that need securing rxrpc: Fix some missing _bh annotations on locking conn->state_lock rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read() rxrpc: Fix rxkad token xdr encoding ... -
Eli Cohen authored
Remove propmt for selecting MLX5_VDPA by the user and modify MLX5_VDPA_NET to select MLX5_VDPA. Also modify MLX5_VDPA_NET to depend on mlx5_core. This fixes an issue where configuration sets 'y' for MLX5_VDPA_NET while MLX5_CORE is compiled as a module causing link errors. Reported-by:
kernel test robot <lkp@intel.com> Fixes: 1a86b377 ("vdpa/mlx5: Add VDPA driver for supported mlx5 device")s Signed-off-by:
Eli Cohen <elic@nvidia.com> Link: https://lore.kernel.org/r/20201007064011.GA50074@mtl-vdi-166.wap.labs.mlnxSigned-off-by:
Michael S. Tsirkin <mst@redhat.com>
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Si-Wei Liu authored
A VM with mlx5 vDPA has below warnings while being reset: vhost VQ 0 ring restore failed: -1: Resource temporarily unavailable (11) vhost VQ 1 ring restore failed: -1: Resource temporarily unavailable (11) We should allow userspace emulating the virtio device be able to get to vq's avail_index, regardless of vDPA device status. Save the index that was last seen when virtq was stopped, so that userspace doesn't complain. Signed-off-by:
Si-Wei Liu <si-wei.liu@oracle.com> Link: https://lore.kernel.org/r/1601583511-15138-1-git-send-email-si-wei.liu@oracle.comSigned-off-by:
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Wilken Gottwalt authored
Add usb ids of the Cellient MPL200 card. Signed-off-by:
Wilken Gottwalt <wilken.gottwalt@mailbox.org> Acked-by:
Bjørn Mork <bjorn@mork.no> Signed-off-by:
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Eric Dumazet authored
De-referencing skb after call to gro_cells_receive() is not allowed. We need to fetch skb->len earlier. Fixes: 5491e7c6 ("macsec: enable GRO and RPS on macsec devices") Signed-off-by:
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Heiner Kallweit authored
Some firmware files trigger a PHY soft reset and don't wait for it to be finished. PHY register writes directly after applying the firmware may fail or provide unexpected results therefore. Fix this by waiting for bit BMCR_RESET to be cleared after applying firmware. There's nothing wrong with the referenced change, it's just that the fix will apply cleanly only after this change. Fixes: 89fbd26c ("r8169: fix firmware not resetting tp->ocp_base") Signed-off-by:
Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by:
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Dumitru Ceara authored
With multiple DNAT rules it's possible that after destination translation the resulting tuples collide. For example, two openvswitch flows: nw_dst=10.0.0.10,tp_dst=10, actions=ct(commit,table=2,nat(dst=20.0.0.1:20)) nw_dst=10.0.0.20,tp_dst=10, actions=ct(commit,table=2,nat(dst=20.0.0.1:20)) Assuming two TCP clients initiating the following connections: 10.0.0.10:5000->10.0.0.10:10 10.0.0.10:5000->10.0.0.20:10 Both tuples would translate to 10.0.0.10:5000->20.0.0.1:20 causing nf_conntrack_confirm() to fail because of tuple collision. Netfilter handles this case by allocating a null binding for SNAT at egress by default. Perform the same operation in openvswitch for DNAT if no explicit SNAT is requested by the user and allocate a null binding for SNAT for packets in the "original" direction. Reported-at: https://bugzilla.redhat.com/1877128Suggested-by:
Florian Westphal <fw@strlen.de> Fixes: 05752523 ("openvswitch: Interface with NAT.") Signed-off-by:
Dumitru Ceara <dceara@redhat.com> Signed-off-by:
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Eric Dumazet authored
After freeing ep->auth_hmacs we have to clear the pointer or risk use-after-free as reported by syzbot: BUG: KASAN: use-after-free in sctp_auth_destroy_hmacs net/sctp/auth.c:509 [inline] BUG: KASAN: use-after-free in sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline] BUG: KASAN: use-after-free in sctp_auth_free+0x17e/0x1d0 net/sctp/auth.c:1070 Read of size 8 at addr ffff8880a8ff52c0 by task syz-executor941/6874 CPU: 0 PID: 6874 Comm: syz-executor941 Not tainted 5.9.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 sctp_auth_destroy_hmacs net/sctp/auth.c:509 [inline] sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline] sctp_auth_free+0x17e/0x1d0 net/sctp/auth.c:1070 sctp_endpoint_destroy+0x95/0x240 net/sctp/endpointola.c:203 sctp_endpoint_put net/sctp/endpointola.c:236 [inline] sctp_endpoint_free+0xd6/0x110 net/sctp/endpointola.c:183 sctp_destroy_sock+0x9c/0x3c0 net/sctp/socket.c:4981 sctp_v6_destroy_sock+0x11/0x20 net/sctp/socket.c:9415 sk_common_release+0x64/0x390 net/core/sock.c:3254 sctp_close+0x4ce/0x8b0 net/sctp/socket.c:1533 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:475 __sock_release+0xcd/0x280 net/socket.c:596 sock_close+0x18/0x20 net/socket.c:1277 __fput+0x285/0x920 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:141 exit_task_work include/linux/task_work.h:25 [inline] do_exit+0xb7d/0x29f0 kernel/exit.c:806 do_group_exit+0x125/0x310 kernel/exit.c:903 __do_sys_exit_group kernel/exit.c:914 [inline] __se_sys_exit_group kernel/exit.c:912 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:912 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x43f278 Code: Bad RIP value. RSP: 002b:00007fffe0995c38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f278 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004bf068 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6874: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmem_cache_alloc_trace+0x174/0x300 mm/slab.c:3554 kmalloc include/linux/slab.h:554 [inline] kmalloc_array include/linux/slab.h:593 [inline] kcalloc include/linux/slab.h:605 [inline] sctp_auth_init_hmacs+0xdb/0x3b0 net/sctp/auth.c:464 sctp_auth_init+0x8a/0x4a0 net/sctp/auth.c:1049 sctp_setsockopt_auth_supported net/sctp/socket.c:4354 [inline] sctp_setsockopt+0x477e/0x97f0 net/sctp/socket.c:4631 __sys_setsockopt+0x2db/0x610 net/socket.c:2132 __do_sys_setsockopt net/socket.c:2143 [inline] __se_sys_setsockopt net/socket.c:2140 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 6874: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3422 [inline] kfree+0x10e/0x2b0 mm/slab.c:3760 sctp_auth_destroy_hmacs net/sctp/auth.c:511 [inline] sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline] sctp_auth_init_hmacs net/sctp/auth.c:496 [inline] sctp_auth_init_hmacs+0x2b7/0x3b0 net/sctp/auth.c:454 sctp_auth_init+0x8a/0x4a0 net/sctp/auth.c:1049 sctp_setsockopt_auth_supported net/sctp/socket.c:4354 [inline] sctp_setsockopt+0x477e/0x97f0 net/sctp/socket.c:4631 __sys_setsockopt+0x2db/0x610 net/socket.c:2132 __do_sys_setsockopt net/socket.c:2143 [inline] __se_sys_setsockopt net/socket.c:2140 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 1f485649 ("[SCTP]: Implement SCTP-AUTH internals") Signed-off-by:
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by:
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Jakub Kicinski authored
Merge tag 'mac80211-for-net-2020-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 Johannes Berg says: ==================== pull-request: mac80211 2020-10-08 A single fix for missing input validation in nl80211. ==================== Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfJakub Kicinski authored
Daniel Borkmann says: ==================== pull-request: bpf 2020-10-08 The main changes are: 1) Fix "unresolved symbol" build error under CONFIG_NET w/o CONFIG_INET due to missing tcp_timewait_sock and inet_timewait_sock BTF, from Yonghong Song. 2) Fix 32 bit sub-register bounds tracking for OR case, from Daniel Borkmann. ==================== Signed-off-by: -
Henrik Bjoernlund authored
This commit is correcting NETLINK br_fill_ifinfo() to be able to handle 'filter_mask' with multiple flags asserted. Fixes: 36a8e8e2 ("bridge: Extend br_fill_ifinfo to return MPR status") Signed-off-by:
Henrik Bjoernlund <henrik.bjoernlund@microchip.com> Reviewed-by:
Horatiu Vultur <horatiu.vultur@microchip.com> Suggested-by:
Nikolay Aleksandrov <nikolay@nvidia.com> Tested-by:
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git://anongit.freedesktop.org/drm/drmLinus Torvalds authored
Pull drm nouveau fixes from Dave Airlie: "Karol found two last minute nouveau fixes, they both fix crashes, the TTM one follows what other drivers do already, and the other is for bailing on load on unrecognised chipsets. - fix crash in TTM alloc fail path - return error earlier for unknown chipsets" * tag 'drm-fixes-2020-10-08' of git://anongit.freedesktop.org/drm/drm: drm/nouveau/mem: guard against NULL pointer access in mem_del drm/nouveau/device: return error for unknown chipsets
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git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfatLinus Torvalds authored
Pull exfat fixes from Namjae Jeon: - Fix use of uninitialized spinlock on error path - Fix missing err assignment in exfat_build_inode() * tag 'exfat-for-5.9-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat: exfat: fix use of uninitialized spinlock on error path exfat: fix pointer error checking
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git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds authored
Pull xen fix from Juergen Gross: "One fix for a regression when booting as a Xen guest on ARM64 introduced probably during the 5.9 cycle. It is very low risk as it is modifying Xen specific code only. The exact commit introducing the bug hasn't been identified yet, but everything was fine in 5.8 and only in 5.9 some configurations started to fail" * tag 'for-linus-5.9b-rc9-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: arm/arm64: xen: Fix to convert percpu address to gfn correctly
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David Howells authored
The afs filesystem has a lock[*] that it uses to serialise I/O operations going to the server (vnode->io_lock), as the server will only perform one modification operation at a time on any given file or directory. This prevents the the filesystem from filling up all the call slots to a server with calls that aren't going to be executed in parallel anyway, thereby allowing operations on other files to obtain slots. [*] Note that is probably redundant for directories at least since i_rwsem is used to serialise directory modifications and lookup/reading vs modification. The server does allow parallel non-modification ops, however. When a file truncation op completes, we truncate the in-memory copy of the file to match - but we do it whilst still holding the io_lock, the idea being to prevent races with other operations. However, if writeback starts in a worker thread simultaneously with truncation (whilst notify_change() is called with i_rwsem locked, writeback pays it no heed), it may manage to set PG_writeback bits on the pages that will get truncated before afs_setattr_success() manages to call truncate_pagecache(). Truncate will then wait for those pages - whilst still inside io_lock: # cat /proc/8837/stack [<0>] wait_on_page_bit_common+0x184/0x1e7 [<0>] truncate_inode_pages_range+0x37f/0x3eb [<0>] truncate_pagecache+0x3c/0x53 [<0>] afs_setattr_success+0x4d/0x6e [<0>] afs_wait_for_operation+0xd8/0x169 [<0>] afs_do_sync_operation+0x16/0x1f [<0>] afs_setattr+0x1fb/0x25d [<0>] notify_change+0x2cf/0x3c4 [<0>] do_truncate+0x7f/0xb2 [<0>] do_sys_ftruncate+0xd1/0x104 [<0>] do_syscall_64+0x2d/0x3a [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 The writeback operation, however, stalls indefinitely because it needs to get the io_lock to proceed: # cat /proc/5940/stack [<0>] afs_get_io_locks+0x58/0x1ae [<0>] afs_begin_vnode_operation+0xc7/0xd1 [<0>] afs_store_data+0x1b2/0x2a3 [<0>] afs_write_back_from_locked_page+0x418/0x57c [<0>] afs_writepages_region+0x196/0x224 [<0>] afs_writepages+0x74/0x156 [<0>] do_writepages+0x2d/0x56 [<0>] __writeback_single_inode+0x84/0x207 [<0>] writeback_sb_inodes+0x238/0x3cf [<0>] __writeback_inodes_wb+0x68/0x9f [<0>] wb_writeback+0x145/0x26c [<0>] wb_do_writeback+0x16a/0x194 [<0>] wb_workfn+0x74/0x177 [<0>] process_one_work+0x174/0x264 [<0>] worker_thread+0x117/0x1b9 [<0>] kthread+0xec/0xf1 [<0>] ret_from_fork+0x1f/0x30 and thus deadlock has occurred. Note that whilst afs_setattr() calls filemap_write_and_wait(), the fact that the caller is holding i_rwsem doesn't preclude more pages being dirtied through an mmap'd region. Fix this by: (1) Use the vnode validate_lock to mediate access between afs_setattr() and afs_writepages(): (a) Exclusively lock validate_lock in afs_setattr() around the whole RPC operation. (b) If WB_SYNC_ALL isn't set on entry to afs_writepages(), trying to shared-lock validate_lock and returning immediately if we couldn't get it. (c) If WB_SYNC_ALL is set, wait for the lock. The validate_lock is also used to validate a file and to zap its cache if the file was altered by a third party, so it's probably a good fit for this. (2) Move the truncation outside of the io_lock in setattr, using the same hook as is used for local directory editing. This requires the old i_size to be retained in the operation record as we commit the revised status to the inode members inside the io_lock still, but we still need to know if we reduced the file size. Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation") Signed-off-by:David Howells <dhowells@redhat.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
In commit 70e806e4 ("mm: Do early cow for pinned pages during fork() for ptes") we write-protected the PTE before doing the page pinning check, in order to avoid a race with concurrent fast-GUP pinning (which doesn't take the mm semaphore or the page table lock). That trick doesn't actually work - it doesn't handle memory ordering properly, and doing so would be prohibitively expensive. It also isn't really needed. While we're moving in the direction of allowing and supporting page pinning without marking the pinned area with MADV_DONTFORK, the fact is that we've never really supported this kind of odd "concurrent fork() and page pinning", and doing the serialization on a pte level is just wrong. We can add serialization with a per-mm sequence counter, so we know how to solve that race properly, but we'll do that at a more appropriate time. Right now this just removes the write protect games. It also turns out that the write protect games actually break on Power, as reported by Aneesh Kumar: "Architecture like ppc64 expects set_pte_at to be not used for updating a valid pte. This is further explained in commit 56eecdb9 ("mm: Use ptep/pmdp_set_numa() for updating _PAGE_NUMA bit")" and the code triggered a warning there: WARNING: CPU: 0 PID: 30613 at arch/powerpc/mm/pgtable.c:185 set_pte_at+0x2a8/0x3a0 arch/powerpc/mm/pgtable.c:185 Call Trace: copy_present_page mm/memory.c:857 [inline] copy_present_pte mm/memory.c:899 [inline] copy_pte_range mm/memory.c:1014 [inline] copy_pmd_range mm/memory.c:1092 [inline] copy_pud_range mm/memory.c:1127 [inline] copy_p4d_range mm/memory.c:1150 [inline] copy_page_range+0x1f6c/0x2cc0 mm/memory.c:1212 dup_mmap kernel/fork.c:592 [inline] dup_mm+0x77c/0xab0 kernel/fork.c:1355 copy_mm kernel/fork.c:1411 [inline] copy_process+0x1f00/0x2740 kernel/fork.c:2070 _do_fork+0xc4/0x10b0 kernel/fork.c:2429 Link: https://lore.kernel.org/lkml/CAHk-=wiWr+gO0Ro4LvnJBMs90OiePNyrE3E+pJvc9PzdBShdmw@mail.gmail.com/ Link: https://lore.kernel.org/linuxppc-dev/20201008092541.398079-1-aneesh.kumar@linux.ibm.com/Reported-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by:
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Anant Thazhemadam authored
In nl80211_parse_key(), key.idx is first initialized as -1. If this value of key.idx remains unmodified and gets returned, and nl80211_key_allowed() also returns 0, then rdev_del_key() gets called with key.idx = -1. This causes an out-of-bounds array access. Handle this issue by checking if the value of key.idx after nl80211_parse_key() is called and return -EINVAL if key.idx < 0. Cc: stable@vger.kernel.org Reported-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com Tested-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com Signed-off-by:
Anant Thazhemadam <anant.thazhemadam@gmail.com> Link: https://lore.kernel.org/r/20201007035401.9522-1-anant.thazhemadam@gmail.comSigned-off-by:
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Daniel Borkmann authored
Simon reported an issue with the current scalar32_min_max_or() implementation. That is, compared to the other 32 bit subreg tracking functions, the code in scalar32_min_max_or() stands out that it's using the 64 bit registers instead of 32 bit ones. This leads to bounds tracking issues, for example: [...] 8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm 8: (79) r1 = *(u64 *)(r0 +0) R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm 9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm 9: (b7) r0 = 1 10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm 10: (18) r2 = 0x600000002 12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 12: (ad) if r1 < r2 goto pc+1 R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 13: (95) exit 14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 14: (25) if r1 > 0x0 goto pc+1 R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 15: (95) exit 16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 16: (47) r1 |= 0 17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x1; 0x700000000),s32_max_value=1,u32_max_value=1) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm [...] The bound tests on the map value force the upper unsigned bound to be 25769803777 in 64 bit (0b11000000000000000000000000000000001) and then lower one to be 1. By using OR they are truncated and thus result in the range [1,1] for the 32 bit reg tracker. This is incorrect given the only thing we know is that the value must be positive and thus 2147483647 (0b1111111111111111111111111111111) at max for the subregs. Fix it by using the {u,s}32_{min,max}_value vars instead. This also makes sense, for example, for the case where we update dst_reg->s32_{min,max}_value in the else branch we need to use the newly computed dst_reg->u32_{min,max}_value as we know that these are positive. Previously, in the else branch the 64 bit values of umin_value=1 and umax_value=32212254719 were used and latter got truncated to be 1 as upper bound there. After the fix the subreg range is now correct: [...] 8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm 8: (79) r1 = *(u64 *)(r0 +0) R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm 9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm 9: (b7) r0 = 1 10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm 10: (18) r2 = 0x600000002 12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 12: (ad) if r1 < r2 goto pc+1 R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 13: (95) exit 14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 14: (25) if r1 > 0x0 goto pc+1 R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 15: (95) exit 16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm 16: (47) r1 |= 0 17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm [...] Fixes: 3f50f132 ("bpf: Verifier, do explicit ALU32 bounds tracking") Reported-by:Simon Scannell <scannell.smn@gmail.com> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Reviewed-by:
John Fastabend <john.fastabend@gmail.com> Acked-by:
Alexei Starovoitov <ast@kernel.org>
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- 07 Oct, 2020 5 commits
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Karol Herbst authored
other drivers seems to do something similar Signed-off-by:
Karol Herbst <kherbst@redhat.com> Cc: dri-devel <dri-devel@lists.freedesktop.org> Cc: Dave Airlie <airlied@redhat.com> Cc: stable@vger.kernel.org Signed-off-by:
Dave Airlie <airlied@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201006220528.13925-2-kherbst@redhat.com
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Karol Herbst authored
Previously the code relied on device->pri to be NULL and to fail probing later. We really should just return an error inside nvkm_device_ctor for unsupported GPUs. Fixes: 24d5ff40 ("drm/nouveau/device: rework mmio mapping code to get rid of second map") Signed-off-by:
Jeremy Cline <jcline@redhat.com> Signed-off-by:
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Namjae Jeon authored
syzbot reported warning message: Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d6/0x29e lib/dump_stack.c:118 register_lock_class+0xf06/0x1520 kernel/locking/lockdep.c:893 __lock_acquire+0xfd/0x2ae0 kernel/locking/lockdep.c:4320 lock_acquire+0x148/0x720 kernel/locking/lockdep.c:5029 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] exfat_cache_inval_inode+0x30/0x280 fs/exfat/cache.c:226 exfat_evict_inode+0x124/0x270 fs/exfat/inode.c:660 evict+0x2bb/0x6d0 fs/inode.c:576 exfat_fill_super+0x1e07/0x27d0 fs/exfat/super.c:681 get_tree_bdev+0x3e9/0x5f0 fs/super.c:1342 vfs_get_tree+0x88/0x270 fs/super.c:1547 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x179d/0x29e0 fs/namespace.c:3192 do_mount fs/namespace.c:3205 [inline] __do_sys_mount fs/namespace.c:3413 [inline] __se_sys_mount+0x126/0x180 fs/namespace.c:3390 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 If exfat_read_root() returns an error, spinlock is used in exfat_evict_inode() without initialization. This patch combines exfat_cache_init_inode() with exfat_inode_init_once() to initialize spinlock by slab constructor. Fixes: c35b6810 ("exfat: add exfat cache") Cc: stable@vger.kernel.org # v5.7+ Reported-by:
syzbot <syzbot+b91107320911a26c9a95@syzkaller.appspotmail.com> Signed-off-by:
Namjae Jeon <namjae.jeon@samsung.com>
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Tetsuhiro Kohada authored
Fix missing result check of exfat_build_inode(). And use PTR_ERR_OR_ZERO instead of PTR_ERR. Signed-off-by:
Tetsuhiro Kohada <kohada.t2@gmail.com> Signed-off-by:
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Masami Hiramatsu authored
Use per_cpu_ptr_to_phys() instead of virt_to_phys() for per-cpu address conversion. In xen_starting_cpu(), per-cpu xen_vcpu_info address is converted to gfn by virt_to_gfn() macro. However, since the virt_to_gfn(v) assumes the given virtual address is in linear mapped kernel memory area, it can not convert the per-cpu memory if it is allocated on vmalloc area. This depends on CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK. If it is enabled, the first chunk of percpu memory is linear mapped. In the other case, that is allocated from vmalloc area. Moreover, if the first chunk of percpu has run out until allocating xen_vcpu_info, it will be allocated on the 2nd chunk, which is based on kernel memory or vmalloc memory (depends on CONFIG_NEED_PER_CPU_KM). Without this fix and kernel configured to use vmalloc area for the percpu memory, the Dom0 kernel will fail to boot with following errors. [ 0.466172] Xen: initializing cpu0 [ 0.469601] ------------[ cut here ]------------ [ 0.474295] WARNING: CPU: 0 PID: 1 at arch/arm64/xen/../../arm/xen/enlighten.c:153 xen_starting_cpu+0x160/0x180 [ 0.484435] Modules linked in: [ 0.487565] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ #4 [ 0.493895] Hardware name: Socionext Developer Box (DT) [ 0.499194] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) [ 0.504836] pc : xen_starting_cpu+0x160/0x180 [ 0.509263] lr : xen_starting_cpu+0xb0/0x180 [ 0.513599] sp : ffff8000116cbb60 [ 0.516984] x29: ffff8000116cbb60 x28: ffff80000abec000 [ 0.522366] x27: 0000000000000000 x26: 0000000000000000 [ 0.527754] x25: ffff80001156c000 x24: fffffdffbfcdb600 [ 0.533129] x23: 0000000000000000 x22: 0000000000000000 [ 0.538511] x21: ffff8000113a99c8 x20: ffff800010fe4f68 [ 0.543892] x19: ffff8000113a9988 x18: 0000000000000010 [ 0.549274] x17: 0000000094fe0f81 x16: 00000000deadbeef [ 0.554655] x15: ffffffffffffffff x14: 0720072007200720 [ 0.560037] x13: 0720072007200720 x12: 0720072007200720 [ 0.565418] x11: 0720072007200720 x10: 0720072007200720 [ 0.570801] x9 : ffff8000100fbdc0 x8 : ffff800010715208 [ 0.576182] x7 : 0000000000000054 x6 : ffff00001b790f00 [ 0.581564] x5 : ffff800010bbf880 x4 : 0000000000000000 [ 0.586945] x3 : 0000000000000000 x2 : ffff80000abec000 [ 0.592327] x1 : 000000000000002f x0 : 0000800000000000 [ 0.597716] Call trace: [ 0.600232] xen_starting_cpu+0x160/0x180 [ 0.604309] cpuhp_invoke_callback+0xac/0x640 [ 0.608736] cpuhp_issue_call+0xf4/0x150 [ 0.612728] __cpuhp_setup_state_cpuslocked+0x128/0x2c8 [ 0.618030] __cpuhp_setup_state+0x84/0xf8 [ 0.622192] xen_guest_init+0x324/0x364 [ 0.626097] do_one_initcall+0x54/0x250 [ 0.630003] kernel_init_freeable+0x12c/0x2c8 [ 0.634428] kernel_init+0x1c/0x128 [ 0.637988] ret_from_fork+0x10/0x18 [ 0.641635] ---[ end trace d95b5309a33f8b27 ]--- [ 0.646337] ------------[ cut here ]------------ [ 0.651005] kernel BUG at arch/arm64/xen/../../arm/xen/enlighten.c:158! [ 0.657697] Internal error: Oops - BUG: 0 [#1] SMP [ 0.662548] Modules linked in: [ 0.665676] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.9.0-rc4+ #4 [ 0.673398] Hardware name: Socionext Developer Box (DT) [ 0.678695] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) [ 0.684338] pc : xen_starting_cpu+0x178/0x180 [ 0.688765] lr : xen_starting_cpu+0x144/0x180 [ 0.693188] sp : ffff8000116cbb60 [ 0.696573] x29: ffff8000116cbb60 x28: ffff80000abec000 [ 0.701955] x27: 0000000000000000 x26: 0000000000000000 [ 0.707344] x25: ffff80001156c000 x24: fffffdffbfcdb600 [ 0.712718] x23: 0000000000000000 x22: 0000000000000000 [ 0.718107] x21: ffff8000113a99c8 x20: ffff800010fe4f68 [ 0.723481] x19: ffff8000113a9988 x18: 0000000000000010 [ 0.728863] x17: 0000000094fe0f81 x16: 00000000deadbeef [ 0.734245] x15: ffffffffffffffff x14: 0720072007200720 [ 0.739626] x13: 0720072007200720 x12: 0720072007200720 [ 0.745008] x11: 0720072007200720 x10: 0720072007200720 [ 0.750390] x9 : ffff8000100fbdc0 x8 : ffff800010715208 [ 0.755771] x7 : 0000000000000054 x6 : ffff00001b790f00 [ 0.761153] x5 : ffff800010bbf880 x4 : 0000000000000000 [ 0.766534] x3 : 0000000000000000 x2 : 00000000deadbeef [ 0.771916] x1 : 00000000deadbeef x0 : ffffffffffffffea [ 0.777304] Call trace: [ 0.779819] xen_starting_cpu+0x178/0x180 [ 0.783898] cpuhp_invoke_callback+0xac/0x640 [ 0.788325] cpuhp_issue_call+0xf4/0x150 [ 0.792317] __cpuhp_setup_state_cpuslocked+0x128/0x2c8 [ 0.797619] __cpuhp_setup_state+0x84/0xf8 [ 0.801779] xen_guest_init+0x324/0x364 [ 0.805683] do_one_initcall+0x54/0x250 [ 0.809590] kernel_init_freeable+0x12c/0x2c8 [ 0.814016] kernel_init+0x1c/0x128 [ 0.817583] ret_from_fork+0x10/0x18 [ 0.821226] Code: d0006980 f9427c00 cb000300 17ffffea (d4210000) [ 0.827415] ---[ end trace d95b5309a33f8b28 ]--- [ 0.832076] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 0.839815] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- Signed-off-by:
Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by:
Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/160196697165.60224.17470743378683334995.stgit@devnote2Signed-off-by:
Juergen Gross <jgross@suse.com>
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- 06 Oct, 2020 5 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 fix from Catalin Marinas: "Fix a kernel panic in the AES crypto code caused by a BR tail call not matching the target BTI instruction (when branch target identification is enabled)" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: crypto: arm64: Use x16 with indirect branch to bti_c
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Linus Torvalds authored
Merge tag 'platform-drivers-x86-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull another x86 platform driver fix from Hans de Goede: "One final pdx86 fix for Tablet Mode reporting regressions (which make the keyboard and touchpad unusable) on various Asus notebooks. These regressions were caused by the asus-nb-wmi and the intel-vbtn drivers both receiving recent patches to start reporting Tablet Mode / to report it on more models. Due to a miscommunication between Andy and me, Andy's earlier pull-req only contained the fix for the intel-vbtn driver and not the fix for the asus-nb-wmi code. This fix has been tested as a downstream patch in Fedora kernels for approx two weeks with no problems being reported" * tag 'platform-drivers-x86-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: platform/x86: asus-wmi: Fix SW_TABLET_MODE always reporting 1 on many different models
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git://anongit.freedesktop.org/drm/drmLinus Torvalds authored
Pull drm fixes from Dave Airlie: "Daniel queued these up last week and I took a long weekend so didn't get them out, but fixing the OOB access on get font seems like something we should land and it's cc'ed stable as well. The other big change is a partial revert for a regression on android on the clcd fbdev driver, and one other docs fix. fbdev: - Re-add FB_ARMCLCD for android - Fix global-out-of-bounds read in fbcon_get_font() core: - Small doc fix" * tag 'drm-fixes-2020-10-06-1' of git://anongit.freedesktop.org/drm/drm: drm: drm_dsc.h: fix a kernel-doc markup Partially revert "video: fbdev: amba-clcd: Retire elder CLCD driver" fbcon: Fix global-out-of-bounds read in fbcon_get_font() Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts fbdev, newport_con: Move FONT_EXTRA_WORDS macros into linux/font.h
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Linus Torvalds authored
Kernel threads intentionally do CLONE_FS in order to follow any changes that 'init' does to set up the root directory (or cwd). It is admittedly a bit odd, but it avoids the situation where 'init' does some extensive setup to initialize the system environment, and then we execute a usermode helper program, and it uses the original FS setup from boot time that may be very limited and incomplete. [ Both Al Viro and Eric Biederman point out that 'pivot_root()' will follow the root regardless, since it fixes up other users of root (see chroot_fs_refs() for details), but overmounting root and doing a chroot() would not. ] However, Vegard Nossum noticed that the CLONE_FS not only means that we follow the root and current working directories, it also means we share umask with whatever init changed it to. That wasn't intentional. Just reset umask to the original default (0022) before actually starting the usermode helper program. Reported-by:
Vegard Nossum <vegard.nossum@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Acked-by:
Eric W. Biederman <ebiederm@xmission.com> Signed-off-by:
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Linus Torvalds authored
Tetsuo Handa reports that splice() can return 0 before the real EOF, if the data in the splice source pipe is an empty pipe buffer. That empty pipe buffer case doesn't happen in any normal situation, but you can trigger it by doing a write to a pipe that fails due to a page fault. Tetsuo has a test-case to show the behavior: #define _GNU_SOURCE #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char *argv[]) { const int fd = open("/tmp/testfile", O_WRONLY | O_CREAT, 0600); int pipe_fd[2] = { -1, -1 }; pipe(pipe_fd); write(pipe_fd[1], NULL, 4096); /* This splice() should wait unless interrupted. */ return !splice(pipe_fd[0], NULL, fd, NULL, 65536, 0); } which results in write(5, NULL, 4096) = -1 EFAULT (Bad address) splice(4, NULL, 3, NULL, 65536, 0) = 0 and this can confuse splice() users into believing they have hit EOF prematurely. The issue was introduced when the pipe write code started pre-allocating the pipe buffers before copying data from user space. This is modified verion of Tetsuo's original patch. Fixes: a194dfe6 ("pipe: Rearrange sequence in pipe_write() to preallocate slot") Link:https://lore.kernel.org/linux-fsdevel/20201005121339.4063-1-penguin-kernel@I-love.SAKURA.ne.jp/Reported-by:Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Acked-by:
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