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2023-03-27rcu: Annotate SRCU's update-side lockdep dependenciesBoqun Feng
Although all flavors of RCU readers are annotated correctly with lockdep as recursive read locks, they do not set the lock_acquire 'check' parameter. This means that RCU read locks are not added to the lockdep dependency graph, which in turn means that lockdep cannot detect RCU-based deadlocks. This is not a problem for RCU flavors having atomic read-side critical sections because context-based annotations can catch these deadlocks, see for example the RCU_LOCKDEP_WARN() statement in synchronize_rcu(). But context-based annotations are not helpful for sleepable RCU, especially given that it is perfectly legal to do synchronize_srcu(&srcu1) within an srcu_read_lock(&srcu2). However, we can detect SRCU-based by: (1) Making srcu_read_lock() a 'check'ed recursive read lock and (2) Making synchronize_srcu() a empty write lock critical section. Even better, with the newly introduced lock_sync(), we can avoid false positives about irq-unsafe/safe. This commit therefore makes it so. Note that NMI-safe SRCU read side critical sections are currently not annotated, but might be annotated in the future. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> [ boqun: Add comments for annotation per Waiman's suggestion ] [ boqun: Fix comment warning reported by Stephen Rothwell ] Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2023-03-27locking/lockdep: Introduce lock_sync()Boqun Feng
Currently, functions like synchronize_srcu() do not have lockdep annotations resembling those of other write-side locking primitives. Such annotations might look as follows: lock_acquire(); lock_release(); Such annotations would tell lockdep that synchronize_srcu() acts like an empty critical section that waits for other (read-side) critical sections to finish. This would definitely catch some deadlock, but as pointed out by Paul Mckenney [1], this could also introduce false positives because of irq-safe/unsafe detection. Of course, there are tricks could help with this: might_sleep(); // Existing statement in __synchronize_srcu(). if (IS_ENABLED(CONFIG_PROVE_LOCKING)) { local_irq_disable(); lock_acquire(); lock_release(); local_irq_enable(); } But it would be better for lockdep to provide a separate annonation for functions like synchronize_srcu(), so that people won't need to repeat the ugly tricks above. Therefore introduce lock_sync(), which is simply an lock+unlock pair with no irq safe/unsafe deadlock check. This works because the to-be-annontated functions do not create real critical sections, and there is therefore no way that irq can create extra dependencies. [1]: https://lore.kernel.org/lkml/20180412021233.ewncg5jjuzjw3x62@tardis/ Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> [ boqun: Fix typos reported by Davidlohr Bueso and Paul E. Mckenney ] Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2023-03-26Merge tag 'sched_urgent_for_v6.3_rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fix from Borislav Petkov: - Fix a corner case where vruntime of a task is not being sanitized * tag 'sched_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Sanitize vruntime of entity being migrated
2023-03-26Merge tag 'core_urgent_for_v6.3_rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core fixes from Borislav Petkov: - Do the delayed RCU wakeup for kthreads in the proper order so that former doesn't get ignored - A noinstr warning fix * tag 'core_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up entry: Fix noinstr warning in __enter_from_user_mode()
2023-03-25bpf: Use bpf_mem_cache_alloc/free for bpf_local_storageMartin KaFai Lau
This patch uses bpf_mem_cache_alloc/free for allocating and freeing bpf_local_storage for task and cgroup storage. The changes are similar to the previous patch. A few things that worth to mention for bpf_local_storage: The local_storage is freed when the last selem is deleted. Before deleting a selem from local_storage, it needs to retrieve the local_storage->smap because the bpf_selem_unlink_storage_nolock() may have set it to NULL. Note that local_storage->smap may have already been NULL when the selem created this local_storage has been removed. In this case, call_rcu will be used to free the local_storage. Also, the bpf_ma (true or false) value is needed before calling bpf_local_storage_free(). The bpf_ma can either be obtained from the local_storage->smap (if available) or any of its selem's smap. A new helper check_storage_bpf_ma() is added to obtain bpf_ma for a deleting bpf_local_storage. When bpf_local_storage_alloc getting a reused memory, all fields are either in the correct values or will be initialized. 'cache[]' must already be all NULLs. 'list' must be empty. Others will be initialized. Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230322215246.1675516-4-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25bpf: Use bpf_mem_cache_alloc/free in bpf_local_storage_elemMartin KaFai Lau
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>
2023-03-25bpf: Add a few bpf mem allocator functionsMartin KaFai Lau
This patch adds a few bpf mem allocator functions which will be used in the bpf_local_storage in a later patch. bpf_mem_cache_alloc_flags(..., gfp_t flags) is added. When the flags == GFP_KERNEL, it will fallback to __alloc(..., GFP_KERNEL). bpf_local_storage knows its running context is sleepable (GFP_KERNEL) and provides a better guarantee on memory allocation. bpf_local_storage has some uncommon cases that its selem cannot be reused immediately. It handles its own rcu_head and goes through a rcu_trace gp and then free it. bpf_mem_cache_raw_free() is added for direct free purpose without leaking the LLIST_NODE_SZ internal knowledge. During free time, the 'struct bpf_mem_alloc *ma' is no longer available. However, the caller should know if it is percpu memory or not and it can call different raw_free functions. bpf_local_storage does not support percpu value, so only the non-percpu 'bpf_mem_cache_raw_free()' is added in this patch. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230322215246.1675516-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGSDavid Vernet
KF_RELEASE kfuncs are not currently treated as having KF_TRUSTED_ARGS, even though they have a superset of the requirements of KF_TRUSTED_ARGS. Like KF_TRUSTED_ARGS, KF_RELEASE kfuncs require a 0-offset argument, and don't allow NULL-able arguments. Unlike KF_TRUSTED_ARGS which require _either_ an argument with ref_obj_id > 0, _or_ (ref->type & BPF_REG_TRUSTED_MODIFIERS) (and no unsafe modifiers allowed), KF_RELEASE only allows for ref_obj_id > 0. Because KF_RELEASE today doesn't automatically imply KF_TRUSTED_ARGS, some of these requirements are enforced in different ways that can make the behavior of the verifier feel unpredictable. For example, a KF_RELEASE kfunc with a NULL-able argument will currently fail in the verifier with a message like, "arg#0 is ptr_or_null_ expected ptr_ or socket" rather than "Possibly NULL pointer passed to trusted arg0". Our intention is the same, but the semantics are different due to implemenetation details that kfunc authors and BPF program writers should not need to care about. Let's make the behavior of the verifier more consistent and intuitive by having KF_RELEASE kfuncs imply the presence of KF_TRUSTED_ARGS. Our eventual goal is to have all kfuncs assume KF_TRUSTED_ARGS by default anyways, so this takes us a step in that direction. Note that it does not make sense to assume KF_TRUSTED_ARGS for all KF_ACQUIRE kfuncs. KF_ACQUIRE kfuncs can have looser semantics than KF_RELEASE, with e.g. KF_RCU | KF_RET_NULL. We may want to have KF_ACQUIRE imply KF_TRUSTED_ARGS _unless_ KF_RCU is specified, but that can be left to another patch set, and there are no such subtleties to address for KF_RELEASE. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20230325213144.486885-4-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25bpf: Remove now-unnecessary NULL checks for KF_RELEASE kfuncsDavid Vernet
Now that we're not invoking kfunc destructors when the kptr in a map was NULL, we no longer require NULL checks in many of our KF_RELEASE kfuncs. This patch removes those NULL checks. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20230325213144.486885-3-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25bpf: Only invoke kptr dtor following non-NULL xchgDavid Vernet
When a map value is being freed, we loop over all of the fields of the corresponding BPF object and issue the appropriate cleanup calls corresponding to the field's type. If the field is a referenced kptr, we atomically xchg the value out of the map, and invoke the kptr's destructor on whatever was there before (or bpf_obj_drop() it if it was a local kptr). Currently, we always invoke the destructor (either bpf_obj_drop() or the kptr's registered destructor) on any KPTR_REF-type field in a map, even if there wasn't a value in the map. This means that any function serving as the kptr's KF_RELEASE destructor must always treat the argument as possibly NULL, as the following can and regularly does happen: void *xchgd_field; /* No value was in the map, so xchgd_field is NULL */ xchgd_field = (void *)xchg(unsigned long *field_ptr, 0); field->kptr.dtor(xchgd_field); These are odd semantics to impose on KF_RELEASE kfuncs -- BPF programs are prohibited by the verifier from passing NULL pointers to KF_RELEASE kfuncs, so it doesn't make sense to require this of BPF programs, but not the main kernel destructor path. It's also unnecessary to invoke any cleanup logic for local kptrs. If there is no object there, there's nothing to drop. So as to allow KF_RELEASE kfuncs to fully assume that an argument is non-NULL, this patch updates a KPTR_REF's destructor to only be invoked when a non-NULL value is xchg'd out of the kptr map field. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20230325213144.486885-2-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25Merge tag 'xfs-6.3-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs percpu counter fixes from Darrick Wong: "We discovered a filesystem summary counter corruption problem that was traced to cpu hot-remove racing with the call to percpu_counter_sum that sets the free block count in the superblock when writing it to disk. The root cause is that percpu_counter_sum doesn't cull from dying cpus and hence misses those counter values if the cpu shutdown hooks have not yet run to merge the values. I'm hoping this is a fairly painless fix to the problem, since the dying cpu mask should generally be empty. It's been in for-next for a week without any complaints from the bots. - Fix a race in the percpu counters summation code where the summation failed to add in the values for any CPUs that were dying but not yet dead. This fixes some minor discrepancies and incorrect assertions when running generic/650" * tag 'xfs-6.3-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: pcpcntr: remove percpu_counter_sum_all() fork: remove use of percpu_counter_sum_all pcpcntrs: fix dying cpu summation race cpumask: introduce for_each_cpu_or
2023-03-24kheaders: Use array declaration instead of charKees Cook
Under CONFIG_FORTIFY_SOURCE, memcpy() will check the size of destination and source buffers. Defining kernel_headers_data as "char" would trip this check. Since these addresses are treated as byte arrays, define them as arrays (as done everywhere else). This was seen with: $ cat /sys/kernel/kheaders.tar.xz >> /dev/null detected buffer overflow in memcpy kernel BUG at lib/string_helpers.c:1027! ... RIP: 0010:fortify_panic+0xf/0x20 [...] Call Trace: <TASK> ikheaders_read+0x45/0x50 [kheaders] kernfs_fop_read_iter+0x1a4/0x2f0 ... Reported-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20230302112130.6e402a98@kernel.org/ Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Tested-by: Jakub Kicinski <kuba@kernel.org> Fixes: 43d8ce9d65a5 ("Provide in-kernel headers to make extending kernel easier") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230302224946.never.243-kees@kernel.org
2023-03-24Merge tag 'mm-hotfixes-stable-2023-03-24-17-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "21 hotfixes, 8 of which are cc:stable. 11 are for MM, the remainder are for other subsystems" * tag 'mm-hotfixes-stable-2023-03-24-17-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (21 commits) mm: mmap: remove newline at the end of the trace mailmap: add entries for Richard Leitner kcsan: avoid passing -g for test kfence: avoid passing -g for test mm: kfence: fix using kfence_metadata without initialization in show_object() lib: dhry: fix unstable smp_processor_id(_) usage mailmap: add entry for Enric Balletbo i Serra mailmap: map Sai Prakash Ranjan's old address to his current one mailmap: map Rajendra Nayak's old address to his current one Revert "kasan: drop skip_kasan_poison variable in free_pages_prepare" mailmap: add entry for Tobias Klauser kasan, powerpc: don't rename memintrinsics if compiler adds prefixes mm/ksm: fix race with VMA iteration and mm_struct teardown kselftest: vm: fix unused variable warning mm: fix error handling for map_deny_write_exec mm: deduplicate error handling for map_deny_write_exec checksyscalls: ignore fstat to silence build warning on LoongArch nilfs2: fix kernel-infoleak in nilfs_ioctl_wrap_copy() test_maple_tree: add more testing for mas_empty_area() maple_tree: fix mas_skip_node() end slot detection ...
2023-03-24bpf: Check IS_ERR for the bpf_map_get() return valueMartin KaFai Lau
This patch fixes a mistake in checking NULL instead of checking IS_ERR for the bpf_map_get() return value. It also fixes the return value in link_update_map() from -EINVAL to PTR_ERR(*_map). Reported-by: syzbot+71ccc0fe37abb458406b@syzkaller.appspotmail.com Fixes: 68b04864ca42 ("bpf: Create links for BPF struct_ops maps.") Fixes: aef56f2e918b ("bpf: Update the struct_ops of a bpf_link.") Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Kui-Feng Lee <kuifeng@meta.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20230324184241.1387437-1-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-24module: already_uses() - reduce pr_debug output volumeJim Cromie
already_uses() is unnecessarily chatty. `modprobe i915` yields 491 messages like: [ 64.108744] i915 uses drm! This is a normal situation, and isn't worth all the log entries. NOTE: I've preserved the "does not use %s" messages, which happens less often, but does happen. Its not clear to me what it tells a reader, or what info might improve the pr_debug's utility. [ 6847.584999] main:already_uses:569: amdgpu does not use ttm! [ 6847.585001] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585014] main:already_uses:569: amdgpu does not use drm! [ 6847.585016] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585024] main:already_uses:569: amdgpu does not use drm_display_helper! [ 6847.585025] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585084] main:already_uses:569: amdgpu does not use drm_kms_helper! [ 6847.585086] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585175] main:already_uses:569: amdgpu does not use drm_buddy! [ 6847.585176] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585202] main:already_uses:569: amdgpu does not use i2c_algo_bit! [ 6847.585204] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585249] main:already_uses:569: amdgpu does not use gpu_sched! [ 6847.585250] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585314] main:already_uses:569: amdgpu does not use video! [ 6847.585315] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585409] main:already_uses:569: amdgpu does not use iommu_v2! [ 6847.585410] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6847.585816] main:already_uses:569: amdgpu does not use drm_ttm_helper! [ 6847.585818] main:add_module_usage:584: Allocating new usage for amdgpu. [ 6848.762268] dyndbg: add-module: amdgpu.2533 sites no functional changes. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: add section-size to move_module pr_debugJim Cromie
move_module() pr_debug's "Final section addresses for $modname". Add section addresses to the message, for anyone looking at these. no functional changes. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: add symbol-name to pr_debug Absolute symbolJim Cromie
The pr_debug("Absolute symbol" ..) reports value, (which is usually 0), but not the name, which is more informative. So add it. no functional changes Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: in layout_sections, move_module: add the modnameJim Cromie
layout_sections() and move_module() each issue ~50 messages for each module loaded. Add mod-name into their 2 header lines, to help the reader find his module. no functional changes. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: fold usermode helper kmod into modules directoryLuis Chamberlain
The kernel/kmod.c is already only built if we enabled modules, so just stuff it under kernel/module/kmod.c and unify the MAINTAINERS file for it. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: merge remnants of setup_load_info() to elf validationLuis Chamberlain
The setup_load_info() was actually had ELF validation checks of its own. To later cache useful variables as an secondary step just means looping again over the ELF sections we just validated. We can simply keep tabs of the key sections of interest as we validate the module ELF section in one swoop, so do that and merge the two routines together. Expand a bit on the documentation / intent / goals. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move more elf validity checks to elf_validity_check()Luis Chamberlain
The symbol and strings section validation currently happen in setup_load_info() but since they are also doing validity checks move this to elf_validity_check(). Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: add stop-grap sanity check on module memcpy()Luis Chamberlain
The integrity of the struct module we load is important, and although our ELF validator already checks that the module section must match struct module, add a stop-gap check before we memcpy() the final minted module. This also makes those inspecting the code what the goal is. While at it, clarify the goal behind updating the sh_addr address. The current comment is pretty misleading. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: add sanity check for ELF module sectionLuis Chamberlain
The ELF ".gnu.linkonce.this_module" section is special, it is what we use to construct the struct module __this_module, which THIS_MODULE points to. When userspace loads a module we always deal first with a copy of the userspace buffer, and twiddle with the userspace copy's version of the struct module. Eventually we allocate memory to do a memcpy() of that struct module, under the assumption that the module size is right. But we have no validity checks against the size or the requirements for the section. Add some validity checks for the special module section early and while at it, cache the module section index early, so we don't have to do that later. While at it, just move over the assigment of the info->mod to make the code clearer. The validity checker also adds an explicit size check to ensure the module section size matches the kernel's run time size for sizeof(struct module). This should prevent sloppy loads of modules which are built today *without* actually increasing the size of the struct module. A developer today can for example expand the size of struct module, rebuild a directoroy 'make fs/xfs/' for example and then try to insmode the driver there. That module would in effect have an incorrect size. This new size check would put a stop gap against such mistakes. This also makes the entire goal of ".gnu.linkonce.this_module" pretty clear. Before this patch verification of the goal / intent required some Indian Jones whips, torches and cleaning up big old spider webs. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: rename check_module_license_and_versions() to ↵Luis Chamberlain
check_export_symbol_versions() This makes the routine easier to understand what the check its checking for. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: converge taint work togetherLuis Chamberlain
Converge on a compromise: so long as we have a module hit our linked list of modules we taint. That is, the module was about to become live. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move signature taint to module_augment_kernel_taints()Luis Chamberlain
Just move the signature taint into the helper: module_augment_kernel_taints() Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move tainting until after a module hits our linked listLuis Chamberlain
It is silly to have taints spread out all over, we can just compromise and add them if the module ever hit our linked list. Our sanity checkers should just prevent crappy drivers / bogus ELF modules / etc and kconfig options should be enough to let you *not* load things you don't want. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: split taint adding with info checkingLuis Chamberlain
check_modinfo() actually does two things: a) sanity checks, some of which are fatal, and so we prevent the user from completing trying to load a module b) taints the kernel The taints are pretty heavy handed because we're tainting the kernel *before* we ever even get to load the module into the modules linked list. That is, it it can fail for other reasons later as we review the module's structure. But this commit makes no functional changes, it just makes the intent clearer and splits the code up where needed to make that happen. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: split taint work out of check_modinfo_livepatch()Luis Chamberlain
The work to taint the kernel due to a module should be split up eventually. To aid with this, split up the tainting on check_modinfo_livepatch(). This let's us bring more early checks together which do return a value, and makes changes easier to read later where we stuff all the work to do the taints in one single routine. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: rename set_license() to module_license_taint_check()Luis Chamberlain
The set_license() routine would seem to a reader to do some sort of setting, but it does not. It just adds a taint if the license is not set or proprietary. This makes what the code is doing clearer, so much we can remove the comment about it. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move check_modinfo() early to early_mod_check()Luis Chamberlain
This moves check_modinfo() to early_mod_check(). This doesn't make any functional changes either, as check_modinfo() was the first call on layout_and_allocate(), so we're just moving it back one routine and at the end. This let's us keep separate the checkers from the allocator. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move early sanity checks into a helperLuis Chamberlain
Move early sanity checkers for the module into a helper. This let's us make it clear when we are working with the local copy of the module prior to allocation. This produces no functional changes, it just makes subsequent changes easier to read. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: add a for_each_modinfo_entry()Luis Chamberlain
Add a for_each_modinfo_entry() to make it easier to read and use. This produces no functional changes but makes this code easiert to read as we are used to with loops in the kernel and trims more lines of code. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: rename next_string() to module_next_tag_pair()Luis Chamberlain
This makes it clearer what it is doing. While at it, make it available to other code other than main.c. This will be used in the subsequent patch and make the changes easier to read. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24module: move get_modinfo() helpers all aboveLuis Chamberlain
Instead of forward declaring routines for get_modinfo() just move everything up. This makes no functional changes. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
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>
2023-03-24kernel/ksysfs.c: use sysfs_emit for sysfs show handlersThomas Weißschuh
sysfs_emit() is the recommended way to format strings for sysfs as per Documentation/filesystems/sysfs.rst. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/r/20230324-ksysfs-sysfs_emit-v1-1-67c03cddc8a6@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-24Merge tag 'net-6.3-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bpf, wifi and bluetooth. Current release - regressions: - wifi: mt76: mt7915: add back 160MHz channel width support for MT7915 - libbpf: revert poisoning of strlcpy, it broke uClibc-ng Current release - new code bugs: - bpf: improve the coverage of the "allow reads from uninit stack" feature to fix verification complexity problems - eth: am65-cpts: reset PPS genf adj settings on enable Previous releases - regressions: - wifi: mac80211: serialize ieee80211_handle_wake_tx_queue() - wifi: mt76: do not run mt76_unregister_device() on unregistered hw, fix null-deref - Bluetooth: btqcomsmd: fix command timeout after setting BD address - eth: igb: revert rtnl_lock() that causes a deadlock - dsa: mscc: ocelot: fix device specific statistics Previous releases - always broken: - xsk: add missing overflow check in xdp_umem_reg() - wifi: mac80211: - fix QoS on mesh interfaces - fix mesh path discovery based on unicast packets - Bluetooth: - ISO: fix timestamped HCI ISO data packet parsing - remove "Power-on" check from Mesh feature - usbnet: more fixes to drivers trusting packet length - wifi: iwlwifi: mvm: fix mvmtxq->stopped handling - Bluetooth: btintel: iterate only bluetooth device ACPI entries - eth: iavf: fix inverted Rx hash condition leading to disabled hash - eth: igc: fix the validation logic for taprio's gate list - dsa: tag_brcm: legacy: fix daisy-chained switches Misc: - bpf: adjust insufficient default bpf_jit_limit to account for growth of BPF use over the last 5 years - xdp: bpf_xdp_metadata() use EOPNOTSUPP as unique errno indicating no driver support" * tag 'net-6.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits) Bluetooth: HCI: Fix global-out-of-bounds Bluetooth: mgmt: Fix MGMT add advmon with RSSI command Bluetooth: btsdio: fix use after free bug in btsdio_remove due to unfinished work Bluetooth: L2CAP: Fix responding with wrong PDU type Bluetooth: btqcomsmd: Fix command timeout after setting BD address Bluetooth: btinel: Check ACPI handle for NULL before accessing net: mdio: thunder: Add missing fwnode_handle_put() net: dsa: mt7530: move setting ssc_delta to PHY_INTERFACE_MODE_TRGMII case net: dsa: mt7530: move lowering TRGMII driving to mt7530_setup() net: dsa: mt7530: move enabling disabling core clock to mt7530_pll_setup() net: asix: fix modprobe "sysfs: cannot create duplicate filename" gve: Cache link_speed value from device tools: ynl: Fix genlmsg header encoding formats net: enetc: fix aggregate RMON counters not showing the ranges Bluetooth: Remove "Power-on" check from Mesh feature Bluetooth: Fix race condition in hci_cmd_sync_clear Bluetooth: btintel: Iterate only bluetooth device ACPI entries Bluetooth: ISO: fix timestamped HCI ISO data packet parsing Bluetooth: btusb: Remove detection of ISO packets over bulk Bluetooth: hci_core: Detect if an ACL packet is in fact an ISO packet ...
2023-03-24trace,smp: Trace all smp_function_call*() invocationsPeter Zijlstra
(Ab)use the trace_ipi_send_cpu*() family to trace all smp_function_call*() invocations, not only those that result in an actual IPI. The queued entries log their callback function while the actual IPIs are traced on generic_smp_call_function_single_interrupt(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2023-03-24trace: Add trace_ipi_send_cpu()Peter Zijlstra
Because copying cpumasks around when targeting a single CPU is a bit daft... Tested-and-reviewed-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230322103004.GA571242%40hirez.programming.kicks-ass.net
2023-03-24sched, smp: Trace smp callback causing an IPIValentin Schneider
Context ======= The newly-introduced ipi_send_cpumask tracepoint has a "callback" parameter which so far has only been fed with NULL. While CSD_TYPE_SYNC/ASYNC and CSD_TYPE_IRQ_WORK share a similar backing struct layout (meaning their callback func can be accessed without caring about the actual CSD type), CSD_TYPE_TTWU doesn't even have a function attached to its struct. This means we need to check the type of a CSD before eventually dereferencing its associated callback. This isn't as trivial as it sounds: the CSD type is stored in __call_single_node.u_flags, which get cleared right before the callback is executed via csd_unlock(). This implies checking the CSD type before it is enqueued on the call_single_queue, as the target CPU's queue can be flushed before we get to sending an IPI. Furthermore, send_call_function_single_ipi() only has a CPU parameter, and would need to have an additional argument to trickle down the invoked function. This is somewhat silly, as the extra argument will always be pushed down to the function even when nothing is being traced, which is unnecessary overhead. Changes ======= send_call_function_single_ipi() is only used by smp.c, and is defined in sched/core.c as it contains scheduler-specific ops (set_nr_if_polling() of a CPU's idle task). Split it into two parts: the scheduler bits remain in sched/core.c, and the actual IPI emission is moved into smp.c. This lets us define an __always_inline helper function that can take the related callback as parameter without creating useless register pressure in the non-traced path which only gains a (disabled) static branch. Do the same thing for the multi IPI case. Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230307143558.294354-8-vschneid@redhat.com
2023-03-24smp: reword smp call IPI commentValentin Schneider
Accessing the call_single_queue hasn't involved a spinlock since 2014: 6897fc22ea01 ("kernel: use lockless list for smp_call_function_single") The llist operations (namely cmpxchg() and xchg()) provide similar ordering guarantees, update the comment to lessen confusion. Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230307143558.294354-7-vschneid@redhat.com
2023-03-24irq_work: Trace self-IPIs sent via arch_irq_work_raise()Valentin Schneider
IPIs sent to remote CPUs via irq_work_queue_on() are now covered by trace_ipi_send_cpumask(), add another instance of the tracepoint to cover self-IPIs. Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20230307143558.294354-5-vschneid@redhat.com
2023-03-24smp: Trace IPIs sent via arch_send_call_function_ipi_mask()Valentin Schneider
This simply wraps around the arch function and prepends it with a tracepoint, similar to send_call_function_single_ipi(). Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20230307143558.294354-4-vschneid@redhat.com
2023-03-24sched, smp: Trace IPIs sent via send_call_function_single_ipi()Valentin Schneider
send_call_function_single_ipi() is the thing that sends IPIs at the bottom of smp_call_function*() via either generic_exec_single() or smp_call_function_many_cond(). Give it an IPI-related tracepoint. Note that this ends up tracing any IPI sent via __smp_call_single_queue(), which covers __ttwu_queue_wakelist() and irq_work_queue_on() "for free". Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20230307143558.294354-3-vschneid@redhat.com
2023-03-24kernel/smp: Make csdlock_debug= resettablePaul E. McKenney
It is currently possible to set the csdlock_debug_enabled static branch, but not to reset it. This is an issue when several different entities supply kernel boot parameters and also for kernels built with CONFIG_CSD_LOCK_WAIT_DEBUG_DEFAULT=y. Therefore, make the csdlock_debug=0 kernel boot parameter turn off debugging. Last one wins! Reported-by: Jes Sorensen <Jes.Sorensen@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230321005516.50558-4-paulmck@kernel.org
2023-03-24locking/csd_lock: Remove per-CPU data indirection from CSD lock debuggingPaul E. McKenney
The diagnostics added by this commit were extremely useful in one instance: a5aabace5fb8 ("locking/csd_lock: Add more data to CSD lock debugging") However, they have not seen much action since, and there have been some concerns expressed that the complexity is not worth the benefit. Therefore, manually revert the following commit preparatory commit: de7b09ef658d ("locking/csd_lock: Prepare more CSD lock debugging") Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230321005516.50558-3-paulmck@kernel.org
2023-03-24locking/csd_lock: Remove added data from CSD lock debuggingPaul E. McKenney
The diagnostics added by this commit were extremely useful in one instance: a5aabace5fb8 ("locking/csd_lock: Add more data to CSD lock debugging") However, they have not seen much action since, and there have been some concerns expressed that the complexity is not worth the benefit. Therefore, manually revert this commit, but leave a comment telling people where to find these diagnostics. [ paulmck: Apply Juergen Gross feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230321005516.50558-2-paulmck@kernel.org
2023-03-24locking/csd_lock: Add Kconfig option for csd_debug defaultPaul E. McKenney
The csd_debug kernel parameter works well, but is inconvenient in cases where it is more closely associated with boot loaders or automation than with a particular kernel version or release. Thererfore, provide a new CSD_LOCK_WAIT_DEBUG_DEFAULT Kconfig option that defaults csd_debug to 1 when selected and 0 otherwise, with this latter being the default. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230321005516.50558-1-paulmck@kernel.org
2023-03-23cpuset: Clean up cpuset_node_allowedHaifeng Xu
Commit 002f290627c2 ("cpuset: use static key better and convert to new API") has used __cpuset_node_allowed() instead of cpuset_node_allowed() to check whether we can allocate on a memory node. Now this function isn't used by anyone, so we can do the follow things to clean up it. 1. remove unused codes 2. rename __cpuset_node_allowed() to cpuset_node_allowed() 3. update comments in mm/page_alloc.c Suggested-by: Waiman Long <longman@redhat.com> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>