kernel/linux.git/include/linux, branch v5.13.12

PCI/MSI: Protect msi_desc::masked for multi-MSI

2021-08-18T07:07:06+00:00

commit 77e89afc25f30abd56e76a809ee2884d7c1b63ce upstream. Multi-MSI uses a single MSI descriptor and there is a single mask register when the device supports per vector masking. To avoid reading back the mask register the value is cached in the MSI descriptor and updates are done by clearing and setting bits in the cache and writing it to the device. But nothing protects msi_desc::masked and the mask register from being modified concurrently on two different CPUs for two different Linux interrupts which belong to the same multi-MSI descriptor. Add a lock to struct device and protect any operation on the mask and the mask register with it. This makes the update of msi_desc::masked unconditional, but there is no place which requires a modification of the hardware register without updating the masked cache. msi_mask_irq() is now an empty wrapper which will be cleaned up in follow up changes. The problem goes way back to the initial support of multi-MSI, but picking the commit which introduced the mask cache is a valid cut off point (2.6.30). Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code") Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Reviewed-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de Signed-off-by: Greg Kroah-Hartman

genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUP

2021-08-18T07:07:03+00:00

commit 826da771291fc25a428e871f9e7fb465e390f852 upstream. X86 IO/APIC and MSI interrupts (when used without interrupts remapping) require that the affinity setup on startup is done before the interrupt is enabled for the first time as the non-remapped operation mode cannot safely migrate enabled interrupts from arbitrary contexts. Provide a new irq chip flag which allows affected hardware to request this. This has to be opt-in because there have been reports in the past that some interrupt chips cannot handle affinity setting before startup. Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Reviewed-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.779791738@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: igmp: increase size of mr_ifc_count

2021-08-18T07:07:02+00:00

[ Upstream commit b69dd5b3780a7298bd893816a09da751bc0636f7 ] Some arches support cmpxchg() on 4-byte and 8-byte only. Increase mr_ifc_count width to 32bit to fix this problem. Fixes: 4a2b285e7e10 ("net: igmp: fix data-race in igmp_ifc_timer_expire()") Signed-off-by: Eric Dumazet Reported-by: Guenter Roeck Link: https://lore.kernel.org/r/20210811195715.3684218-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

bpf: Fix potentially incorrect results with bpf_get_local_storage()

2021-08-18T07:06:59+00:00

[ Upstream commit a2baf4e8bb0f306fbed7b5e6197c02896a638ab5 ] Commit b910eaaaa4b8 ("bpf: Fix NULL pointer dereference in bpf_get_local_storage() helper") fixed a bug for bpf_get_local_storage() helper so different tasks won't mess up with each other's percpu local storage. The percpu data contains 8 slots so it can hold up to 8 contexts (same or different tasks), for 8 different program runs, at the same time. This in general is sufficient. But our internal testing showed the following warning multiple times: [...] warning: WARNING: CPU: 13 PID: 41661 at include/linux/bpf-cgroup.h:193 __cgroup_bpf_run_filter_sock_ops+0x13e/0x180 RIP: 0010:__cgroup_bpf_run_filter_sock_ops+0x13e/0x180 tcp_call_bpf.constprop.99+0x93/0xc0 tcp_conn_request+0x41e/0xa50 ? tcp_rcv_state_process+0x203/0xe00 tcp_rcv_state_process+0x203/0xe00 ? sk_filter_trim_cap+0xbc/0x210 ? tcp_v6_inbound_md5_hash.constprop.41+0x44/0x160 tcp_v6_do_rcv+0x181/0x3e0 tcp_v6_rcv+0xc65/0xcb0 ip6_protocol_deliver_rcu+0xbd/0x450 ip6_input_finish+0x11/0x20 ip6_input+0xb5/0xc0 ip6_sublist_rcv_finish+0x37/0x50 ip6_sublist_rcv+0x1dc/0x270 ipv6_list_rcv+0x113/0x140 __netif_receive_skb_list_core+0x1a0/0x210 netif_receive_skb_list_internal+0x186/0x2a0 gro_normal_list.part.170+0x19/0x40 napi_complete_done+0x65/0x150 mlx5e_napi_poll+0x1ae/0x680 __napi_poll+0x25/0x120 net_rx_action+0x11e/0x280 __do_softirq+0xbb/0x271 irq_exit_rcu+0x97/0xa0 common_interrupt+0x7f/0xa0 asm_common_interrupt+0x1e/0x40 RIP: 0010:bpf_prog_1835a9241238291a_tw_egress+0x5/0xbac ? __cgroup_bpf_run_filter_skb+0x378/0x4e0 ? do_softirq+0x34/0x70 ? ip6_finish_output2+0x266/0x590 ? ip6_finish_output+0x66/0xa0 ? ip6_output+0x6c/0x130 ? ip6_xmit+0x279/0x550 ? ip6_dst_check+0x61/0xd0 [...] Using drgn [0] to dump the percpu buffer contents showed that on this CPU slot 0 is still available, but slots 1-7 are occupied and those tasks in slots 1-7 mostly don't exist any more. So we might have issues in bpf_cgroup_storage_unset(). Further debugging confirmed that there is a bug in bpf_cgroup_storage_unset(). Currently, it tries to unset "current" slot with searching from the start. So the following sequence is possible: 1. A task is running and claims slot 0 2. Running BPF program is done, and it checked slot 0 has the "task" and ready to reset it to NULL (not yet). 3. An interrupt happens, another BPF program runs and it claims slot 1 with the *same* task. 4. The unset() in interrupt context releases slot 0 since it matches "task". 5. Interrupt is done, the task in process context reset slot 0. At the end, slot 1 is not reset and the same process can continue to occupy slots 2-7 and finally, when the above step 1-5 is repeated again, step 3 BPF program won't be able to claim an empty slot and a warning will be issued. To fix the issue, for unset() function, we should traverse from the last slot to the first. This way, the above issue can be avoided. The same reverse traversal should also be done in bpf_get_local_storage() helper itself. Otherwise, incorrect local storage may be returned to BPF program. [0] https://github.com/osandov/drgn Fixes: b910eaaaa4b8 ("bpf: Fix NULL pointer dereference in bpf_get_local_storage() helper") Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210810010413.1976277-1-yhs@fb.com Signed-off-by: Sasha Levin

net/mlx5: Synchronize correct IRQ when destroying CQ

2021-08-18T07:06:58+00:00

[ Upstream commit 563476ae0c5e48a028cbfa38fa9d2fc0418eb88f ] The CQ destroy is performed based on the IRQ number that is stored in cq->irqn. That number wasn't set explicitly during CQ creation and as expected some of the API users of mlx5_core_create_cq() forgot to update it. This caused to wrong synchronization call of the wrong IRQ with a number 0 instead of the real one. As a fix, set the IRQ number directly in the mlx5_core_create_cq() and update all users accordingly. Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices") Fixes: ef1659ade359 ("IB/mlx5: Add DEVX support for CQ events") Signed-off-by: Shay Drory Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin

bpf: Add lockdown check for probe_write_user helper

2021-08-15T12:01:56+00:00

commit 51e1bb9eeaf7868db56e58f47848e364ab4c4129 upstream. Back then, commit 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") added the bpf_probe_write_user() helper in order to allow to override user space memory. Its original goal was to have a facility to "debug, divert, and manipulate execution of semi-cooperative processes" under CAP_SYS_ADMIN. Write to kernel was explicitly disallowed since it would otherwise tamper with its integrity. One use case was shown in cf9b1199de27 ("samples/bpf: Add test/example of using bpf_probe_write_user bpf helper") where the program DNATs traffic at the time of connect(2) syscall, meaning, it rewrites the arguments to a syscall while they're still in userspace, and before the syscall has a chance to copy the argument into kernel space. These days we have better mechanisms in BPF for achieving the same (e.g. for load-balancers), but without having to write to userspace memory. Of course the bpf_probe_write_user() helper can also be used to abuse many other things for both good or bad purpose. Outside of BPF, there is a similar mechanism for ptrace(2) such as PTRACE_PEEK{TEXT,DATA} and PTRACE_POKE{TEXT,DATA}, but would likely require some more effort. Commit 96ae52279594 explicitly dedicated the helper for experimentation purpose only. Thus, move the helper's availability behind a newly added LOCKDOWN_BPF_WRITE_USER lockdown knob so that the helper is disabled under the "integrity" mode. More fine-grained control can be implemented also from LSM side with this change. Fixes: 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Signed-off-by: Greg Kroah-Hartman

serial: 8250: fix handle_irq locking

2021-08-12T11:32:20+00:00

commit 853a9ae29e978d37f5dfa72622a68c9ae3d7fa89 upstream. The 8250 handle_irq callback is not just called from the interrupt handler but also from a timer callback when polling (e.g. for ports without an interrupt line). Consequently the callback must explicitly disable interrupts to avoid a potential deadlock with another interrupt in polled mode. Add back an irqrestore-version of the sysrq port-unlock helper and use it in the 8250 callbacks that need it. Fixes: 75f4e830fa9c ("serial: do not restore interrupt state in sysrq helper") Cc: stable@vger.kernel.org # 5.13 Cc: Joel Stanley Cc: Andrew Jeffery Reported-by: kernel test robot Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210714080427.28164-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tee: Correct inappropriate usage of TEE_SHM_DMA_BUF flag

2021-08-12T11:32:18+00:00

commit 376e4199e327a5cf29b8ec8fb0f64f3d8b429819 upstream. Currently TEE_SHM_DMA_BUF flag has been inappropriately used to not register shared memory allocated for private usage by underlying TEE driver: OP-TEE in this case. So rather add a new flag as TEE_SHM_PRIV that can be utilized by underlying TEE drivers for private allocation and usage of shared memory. With this corrected, allow tee_shm_alloc_kernel_buf() to allocate a shared memory region without the backing of dma-buf. Cc: stable@vger.kernel.org Signed-off-by: Sumit Garg Co-developed-by: Tyler Hicks Signed-off-by: Tyler Hicks Reviewed-by: Jens Wiklander Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander Signed-off-by: Greg Kroah-Hartman

tee: add tee_shm_alloc_kernel_buf()

2021-08-12T11:32:18+00:00

commit dc7019b7d0e188d4093b34bd0747ed0d668c63bf upstream. Adds a new function tee_shm_alloc_kernel_buf() to allocate shared memory from a kernel driver. This function can later be made more lightweight by unnecessary dma-buf export. Cc: stable@vger.kernel.org Reviewed-by: Tyler Hicks Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander Signed-off-by: Greg Kroah-Hartman

usb: otg-fsm: Fix hrtimer list corruption

2021-08-12T11:32:16+00:00

commit bf88fef0b6f1488abeca594d377991171c00e52a upstream. The HNP work can be re-scheduled while it's still in-fly. This results in re-initialization of the busy work, resetting the hrtimer's list node of the work and crashing kernel with null dereference within kernel/timer once work's timer is expired. It's very easy to trigger this problem by re-plugging USB cable quickly. Initialize HNP work only once to fix this trouble. Unable to handle kernel NULL pointer dereference at virtual address 00000126) ... PC is at __run_timers.part.0+0x150/0x228 LR is at __next_timer_interrupt+0x51/0x9c ... (__run_timers.part.0) from [] (run_timer_softirq+0x2f/0x50) (run_timer_softirq) from [] (__do_softirq+0xd5/0x2f0) (__do_softirq) from [] (irq_exit+0xab/0xb8) (irq_exit) from [] (handle_domain_irq+0x45/0x60) (handle_domain_irq) from [] (gic_handle_irq+0x6b/0x7c) (gic_handle_irq) from [] (__irq_svc+0x65/0xac) Cc: stable@vger.kernel.org Acked-by: Peter Chen Signed-off-by: Dmitry Osipenko Link: https://lore.kernel.org/r/20210717182134.30262-6-digetx@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman