user/sven/linux.git/kernel, branch v4.19.280

cgroup: Add missing cpus_read_lock() to cgroup_attach_task_all()

2023-04-05T09:15:43Z

commit 43626dade36fa74d3329046f4ae2d7fdefe401c6 upstream. syzbot is hitting percpu_rwsem_assert_held(&cpu_hotplug_lock) warning at cpuset_attach() [1], for commit 4f7e7236435ca0ab ("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock") missed that cpuset_attach() is also called from cgroup_attach_task_all(). Add cpus_read_lock() like what cgroup_procs_write_start() does. Link: https://syzkaller.appspot.com/bug?extid=29d3a3b4d86c8136ad9e [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Fixes: 4f7e7236435ca0ab ("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock") Signed-off-by: Tejun Heo Signed-off-by: Cai Xinchen Signed-off-by: Greg Kroah-Hartman

cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock

2023-04-05T09:15:43Z

commit 4f7e7236435ca0abe005c674ebd6892c6e83aeb3 upstream. Add #include to avoid compile error on some architectures. commit 9a3284fad42f6 ("cgroup: Optimize single thread migration") and commit 671c11f0619e5 ("cgroup: Elide write-locking threadgroup_rwsem when updating csses on an empty subtree") are not backport. So ignore the input parameter of cgroup_attach_lock/cgroup_attach_unlock. original commit message: Bringing up a CPU may involve creating and destroying tasks which requires read-locking threadgroup_rwsem, so threadgroup_rwsem nests inside cpus_read_lock(). However, cpuset's ->attach(), which may be called with thredagroup_rwsem write-locked, also wants to disable CPU hotplug and acquires cpus_read_lock(), leading to a deadlock. Fix it by guaranteeing that ->attach() is always called with CPU hotplug disabled and removing cpus_read_lock() call from cpuset_attach(). Signed-off-by: Tejun Heo Reviewed-and-tested-by: Imran Khan Reported-and-tested-by: Xuewen Yan Fixes: 05c7b7a92cc8 ("cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug") Cc: stable@vger.kernel.org # v5.17+ Signed-off-by: Cai Xinchen Signed-off-by: Greg Kroah-Hartman

cgroup/cpuset: Change cpuset_rwsem and hotplug lock order

2023-04-05T09:15:42Z

commit d74b27d63a8bebe2fe634944e4ebdc7b10db7a39 upstream. commit 1243dc518c9da ("cgroup/cpuset: Convert cpuset_mutex to percpu_rwsem") is performance patch which is not backport. So convert percpu_rwsem to cpuset_mutex. commit aa44002e7db25 ("cpuset: Fix unsafe lock order between cpuset lock and cpuslock") makes lock order keep cpuset_mutex ->cpu_hotplug_lock. We should change lock order in cpuset_attach. original commit message: cpuset_rwsem is going to be acquired from sched_setscheduler() with a following patch. There are however paths (e.g., spawn_ksoftirqd) in which sched_scheduler() is eventually called while holding hotplug lock; this creates a dependecy between hotplug lock (to be always acquired first) and cpuset_rwsem (to be always acquired after hotplug lock). Fix paths which currently take the two locks in the wrong order (after a following patch is applied). Tested-by: Dietmar Eggemann Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bristot@redhat.com Cc: claudio@evidence.eu.com Cc: lizefan@huawei.com Cc: longman@redhat.com Cc: luca.abeni@santannapisa.it Cc: mathieu.poirier@linaro.org Cc: rostedt@goodmis.org Cc: tj@kernel.org Cc: tommaso.cucinotta@santannapisa.it Link: https://lkml.kernel.org/r/20190719140000.31694-7-juri.lelli@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Cai Xinchen Signed-off-by: Greg Kroah-Hartman

sched_getaffinity: don't assume 'cpumask_size()' is fully initialized

2023-04-05T09:15:39Z

[ Upstream commit 6015b1aca1a233379625385feb01dd014aca60b5 ] The getaffinity() system call uses 'cpumask_size()' to decide how big the CPU mask is - so far so good. It is indeed the allocation size of a cpumask. But the code also assumes that the whole allocation is initialized without actually doing so itself. That's wrong, because we might have fixed-size allocations (making copying and clearing more efficient), but not all of it is then necessarily used if 'nr_cpu_ids' is smaller. Having checked other users of 'cpumask_size()', they all seem to be ok, either using it purely for the allocation size, or explicitly zeroing the cpumask before using the size in bytes to copy it. See for example the ublk_ctrl_get_queue_affinity() function that uses the proper 'zalloc_cpumask_var()' to make sure that the whole mask is cleared, whether the storage is on the stack or if it was an external allocation. Fix this by just zeroing the allocation before using it. Do the same for the compat version of sched_getaffinity(), which had the same logic. Also, for consistency, make sched_getaffinity() use 'cpumask_bits()' to access the bits. For a cpumask_var_t, it ends up being a pointer to the same data either way, but it's just a good idea to treat it like you would a 'cpumask_t'. The compat case already did that. Reported-by: Ryan Roberts Link: https://lore.kernel.org/lkml/7d026744-6bd6-6827-0471-b5e8eae0be3f@arm.com/ Cc: Yury Norov Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

sched/fair: Sanitize vruntime of entity being migrated

2023-04-05T09:15:38Z

commit a53ce18cacb477dd0513c607f187d16f0fa96f71 upstream. Commit 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") fixes an overflowing bug, but ignore a case that se->exec_start is reset after a migration. For fixing this case, we delay the reset of se->exec_start after placing the entity which se->exec_start to detect long sleeping task. In order to take into account a possible divergence between the clock_task of 2 rqs, we increase the threshold to around 104 days. Fixes: 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") Originally-by: Zhang Qiao Signed-off-by: Vincent Guittot Signed-off-by: Peter Zijlstra (Intel) Tested-by: Zhang Qiao Link: https://lore.kernel.org/r/20230317160810.107988-1-vincent.guittot@linaro.org Signed-off-by: Greg Kroah-Hartman

sched/fair: sanitize vruntime of entity being placed

2023-04-05T09:15:38Z

commit 829c1651e9c4a6f78398d3e67651cef9bb6b42cc upstream. When a scheduling entity is placed onto cfs_rq, its vruntime is pulled to the base level (around cfs_rq->min_vruntime), so that the entity doesn't gain extra boost when placed backwards. However, if the entity being placed wasn't executed for a long time, its vruntime may get too far behind (e.g. while cfs_rq was executing a low-weight hog), which can inverse the vruntime comparison due to s64 overflow. This results in the entity being placed with its original vruntime way forwards, so that it will effectively never get to the cpu. To prevent that, ignore the vruntime of the entity being placed if it didn't execute for much longer than the characteristic sheduler time scale. [rkagan: formatted, adjusted commit log, comments, cutoff value] Signed-off-by: Zhang Qiao Co-developed-by: Roman Kagan Signed-off-by: Roman Kagan Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20230130122216.3555094-1-rkagan@amazon.de Signed-off-by: Greg Kroah-Hartman

bpf: Adjust insufficient default bpf_jit_limit

2023-04-05T09:15:34Z

[ Upstream commit 10ec8ca8ec1a2f04c4ed90897225231c58c124a7 ] We've seen recent AWS EKS (Kubernetes) user reports like the following: After upgrading EKS nodes from v20230203 to v20230217 on our 1.24 EKS clusters after a few days a number of the nodes have containers stuck in ContainerCreating state or liveness/readiness probes reporting the following error: Readiness probe errored: rpc error: code = Unknown desc = failed to exec in container: failed to start exec "4a11039f730203ffc003b7[...]": OCI runtime exec failed: exec failed: unable to start container process: unable to init seccomp: error loading seccomp filter into kernel: error loading seccomp filter: errno 524: unknown However, we had not been seeing this issue on previous AMIs and it only started to occur on v20230217 (following the upgrade from kernel 5.4 to 5.10) with no other changes to the underlying cluster or workloads. We tried the suggestions from that issue (sysctl net.core.bpf_jit_limit=452534528) which helped to immediately allow containers to be created and probes to execute but after approximately a day the issue returned and the value returned by cat /proc/vmallocinfo | grep bpf_jit | awk '{s+=$2} END {print s}' was steadily increasing. I tested bpf tree to observe bpf_jit_charge_modmem, bpf_jit_uncharge_modmem their sizes passed in as well as bpf_jit_current under tcpdump BPF filter, seccomp BPF and native (e)BPF programs, and the behavior all looks sane and expected, that is nothing "leaking" from an upstream perspective. The bpf_jit_limit knob was originally added in order to avoid a situation where unprivileged applications loading BPF programs (e.g. seccomp BPF policies) consuming all the module memory space via BPF JIT such that loading of kernel modules would be prevented. The default limit was defined back in 2018 and while good enough back then, we are generally seeing far more BPF consumers today. Adjust the limit for the BPF JIT pool from originally 1/4 to now 1/2 of the module memory space to better reflect today's needs and avoid more users running into potentially hard to debug issues. Fixes: fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K") Reported-by: Stephen Haynes Reported-by: Lefteris Alexakis Signed-off-by: Daniel Borkmann Link: https://github.com/awslabs/amazon-eks-ami/issues/1179 Link: https://github.com/awslabs/amazon-eks-ami/issues/1219 Reviewed-by: Kuniyuki Iwashima Link: https://lore.kernel.org/r/20230320143725.8394-1-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

ftrace: Fix invalid address access in lookup_rec() when index is 0

2023-03-22T12:27:12Z

commit ee92fa443358f4fc0017c1d0d325c27b37802504 upstream. KASAN reported follow problem: BUG: KASAN: use-after-free in lookup_rec Read of size 8 at addr ffff000199270ff0 by task modprobe CPU: 2 Comm: modprobe Call trace: kasan_report __asan_load8 lookup_rec ftrace_location arch_check_ftrace_location check_kprobe_address_safe register_kprobe When checking pg->records[pg->index - 1].ip in lookup_rec(), it can get a pg which is newly added to ftrace_pages_start in ftrace_process_locs(). Before the first pg->index++, index is 0 and accessing pg->records[-1].ip will cause this problem. Don't check the ip when pg->index is 0. Link: https://lore.kernel.org/linux-trace-kernel/20230309080230.36064-1-chenzhongjin@huawei.com Cc: stable@vger.kernel.org Fixes: 9644302e3315 ("ftrace: Speed up search by skipping pages by address") Suggested-by: Steven Rostedt (Google) Signed-off-by: Chen Zhongjin Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tracing: Check field value in hist_field_name()

2023-03-22T12:27:11Z

commit 9f116f76fa8c04c81aef33ad870dbf9a158e5b70 upstream. The function hist_field_name() cannot handle being passed a NULL field parameter. It should never be NULL, but due to a previous bug, NULL was passed to the function and the kernel crashed due to a NULL dereference. Mark Rutland reported this to me on IRC. The bug was fixed, but to prevent future bugs from crashing the kernel, check the field and add a WARN_ON() if it is NULL. Link: https://lkml.kernel.org/r/20230302020810.762384440@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Andrew Morton Reported-by: Mark Rutland Fixes: c6afad49d127f ("tracing: Add hist trigger 'sym' and 'sym-offset' modifiers") Tested-by: Mark Rutland Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tracing: Add NULL checks for buffer in ring_buffer_free_read_page()

2023-03-11T15:31:59Z

[ Upstream commit 3e4272b9954094907f16861199728f14002fcaf6 ] In a previous commit 7433632c9ff6, buffer, buffer->buffers and buffer->buffers[cpu] in ring_buffer_wake_waiters() can be NULL, and thus the related checks are added. However, in the same call stack, these variables are also used in ring_buffer_free_read_page(): tracing_buffers_release() ring_buffer_wake_waiters(iter->array_buffer->buffer) cpu_buffer = buffer->buffers[cpu] -> Add checks by previous commit ring_buffer_free_read_page(iter->array_buffer->buffer) cpu_buffer = buffer->buffers[cpu] -> No check Thus, to avod possible null-pointer derefernces, the related checks should be added. These results are reported by a static tool designed by myself. Link: https://lkml.kernel.org/r/20230113125501.760324-1-baijiaju1990@gmail.com Reported-by: TOTE Robot Signed-off-by: Jia-Ju Bai Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin