user/sven/linux.git/kernel/padata.c, branch v6.11.3

padata: use integer wrap around to prevent deadlock on seq_nr overflow

2024-10-04T14:38:51Z

commit 9a22b2812393d93d84358a760c347c21939029a6 upstream. When submitting more than 2^32 padata objects to padata_do_serial, the current sorting implementation incorrectly sorts padata objects with overflowed seq_nr, causing them to be placed before existing objects in the reorder list. This leads to a deadlock in the serialization process as padata_find_next cannot match padata->seq_nr and pd->processed because the padata instance with overflowed seq_nr will be selected next. To fix this, we use an unsigned integer wrap around to correctly sort padata objects in scenarios with integer overflow. Fixes: bfde23ce200e ("padata: unbind parallel jobs from specific CPUs") Cc: Co-developed-by: Christian Gafert Signed-off-by: Christian Gafert Co-developed-by: Max Ferger Signed-off-by: Max Ferger Signed-off-by: Van Giang Nguyen Acked-by: Daniel Jordan Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

padata: Honor the caller's alignment in case of chunk_size 0

2024-10-04T14:37:22Z

[ Upstream commit 24cc57d8faaa4060fd58adf810b858fcfb71a02f ] In the case where we are forcing the ps.chunk_size to be at least 1, we are ignoring the caller's alignment. Move the forcing of ps.chunk_size to be at least 1 before rounding it up to caller's alignment, so that caller's alignment is honored. While at it, use max() to force the ps.chunk_size to be at least 1 to improve readability. Fixes: 6d45e1c948a8 ("padata: Fix possible divide-by-0 panic in padata_mt_helper()") Signed-off-by: Kamlesh Gurudasani Acked-by: Waiman Long Acked-by: Daniel Jordan Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

padata: Fix possible divide-by-0 panic in padata_mt_helper()

2024-08-08T01:33:56Z

We are hit with a not easily reproducible divide-by-0 panic in padata.c at bootup time. [ 10.017908] Oops: divide error: 0000 1 PREEMPT SMP NOPTI [ 10.017908] CPU: 26 PID: 2627 Comm: kworker/u1666:1 Not tainted 6.10.0-15.el10.x86_64 #1 [ 10.017908] Hardware name: Lenovo ThinkSystem SR950 [7X12CTO1WW]/[7X12CTO1WW], BIOS [PSE140J-2.30] 07/20/2021 [ 10.017908] Workqueue: events_unbound padata_mt_helper [ 10.017908] RIP: 0010:padata_mt_helper+0x39/0xb0 : [ 10.017963] Call Trace: [ 10.017968] [ 10.018004] ? padata_mt_helper+0x39/0xb0 [ 10.018084] process_one_work+0x174/0x330 [ 10.018093] worker_thread+0x266/0x3a0 [ 10.018111] kthread+0xcf/0x100 [ 10.018124] ret_from_fork+0x31/0x50 [ 10.018138] ret_from_fork_asm+0x1a/0x30 [ 10.018147] Looking at the padata_mt_helper() function, the only way a divide-by-0 panic can happen is when ps->chunk_size is 0. The way that chunk_size is initialized in padata_do_multithreaded(), chunk_size can be 0 when the min_chunk in the passed-in padata_mt_job structure is 0. Fix this divide-by-0 panic by making sure that chunk_size will be at least 1 no matter what the input parameters are. Link: https://lkml.kernel.org/r/20240806174647.1050398-1-longman@redhat.com Fixes: 004ed42638f4 ("padata: add basic support for multithreaded jobs") Signed-off-by: Waiman Long Cc: Daniel Jordan Cc: Steffen Klassert Cc: Waiman Long Cc: Signed-off-by: Andrew Morton

padata: Disable BH when taking works lock on MT path

2024-04-12T07:07:51Z

As the old padata code can execute in softirq context, disable softirqs for the new padata_do_mutithreaded code too as otherwise lockdep will get antsy. Reported-by: syzbot+0cb5bb0f4bf9e79db3b3@syzkaller.appspotmail.com Signed-off-by: Herbert Xu Acked-by: Daniel Jordan Signed-off-by: Herbert Xu

Author: Gang Li padata: dispatch works on

2024-03-06T21:04:17Z

different nodes Date: Thu, 22 Feb 2024 22:04:17 +0800 When a group of tasks that access different nodes are scheduled on the same node, they may encounter bandwidth bottlenecks and access latency. Thus, numa_aware flag is introduced here, allowing tasks to be distributed across different nodes to fully utilize the advantage of multi-node systems. Link: https://lkml.kernel.org/r/20240222140422.393911-5-gang.li@linux.dev Signed-off-by: Gang Li Tested-by: David Rientjes Reviewed-by: Muchun Song Reviewed-by: Tim Chen Cc: Alexey Dobriyan Cc: Daniel Jordan Cc: David Hildenbrand Cc: Jane Chu Cc: Mike Kravetz Cc: Paul E. McKenney Cc: Randy Dunlap Cc: Steffen Klassert Signed-off-by: Andrew Morton

padata: Fix refcnt handling in padata_free_shell()

2023-10-27T10:04:24Z

In a high-load arm64 environment, the pcrypt_aead01 test in LTP can lead to system UAF (Use-After-Free) issues. Due to the lengthy analysis of the pcrypt_aead01 function call, I'll describe the problem scenario using a simplified model: Suppose there's a user of padata named `user_function` that adheres to the padata requirement of calling `padata_free_shell` after `serial()` has been invoked, as demonstrated in the following code: ```c struct request { struct padata_priv padata; struct completion *done; }; void parallel(struct padata_priv *padata) { do_something(); } void serial(struct padata_priv *padata) { struct request *request = container_of(padata, struct request, padata); complete(request->done); } void user_function() { DECLARE_COMPLETION(done) padata->parallel = parallel; padata->serial = serial; padata_do_parallel(); wait_for_completion(&done); padata_free_shell(); } ``` In the corresponding padata.c file, there's the following code: ```c static void padata_serial_worker(struct work_struct *serial_work) { ... cnt = 0; while (!list_empty(&local_list)) { ... padata->serial(padata); cnt++; } local_bh_enable(); if (refcount_sub_and_test(cnt, &pd->refcnt)) padata_free_pd(pd); } ``` Because of the high system load and the accumulation of unexecuted softirq at this moment, `local_bh_enable()` in padata takes longer to execute than usual. Subsequently, when accessing `pd->refcnt`, `pd` has already been released by `padata_free_shell()`, resulting in a UAF issue with `pd->refcnt`. The fix is straightforward: add `refcount_dec_and_test` before calling `padata_free_pd` in `padata_free_shell`. Fixes: 07928d9bfc81 ("padata: Remove broken queue flushing") Signed-off-by: WangJinchao Acked-by: Daniel Jordan Acked-by: Daniel Jordan Signed-off-by: Herbert Xu

crypto: pcrypt - Fix hungtask for PADATA_RESET

2023-09-15T10:29:45Z

We found a hungtask bug in test_aead_vec_cfg as follows: INFO: task cryptomgr_test:391009 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Call trace: __switch_to+0x98/0xe0 __schedule+0x6c4/0xf40 schedule+0xd8/0x1b4 schedule_timeout+0x474/0x560 wait_for_common+0x368/0x4e0 wait_for_completion+0x20/0x30 wait_for_completion+0x20/0x30 test_aead_vec_cfg+0xab4/0xd50 test_aead+0x144/0x1f0 alg_test_aead+0xd8/0x1e0 alg_test+0x634/0x890 cryptomgr_test+0x40/0x70 kthread+0x1e0/0x220 ret_from_fork+0x10/0x18 Kernel panic - not syncing: hung_task: blocked tasks For padata_do_parallel, when the return err is 0 or -EBUSY, it will call wait_for_completion(&wait->completion) in test_aead_vec_cfg. In normal case, aead_request_complete() will be called in pcrypt_aead_serial and the return err is 0 for padata_do_parallel. But, when pinst->flags is PADATA_RESET, the return err is -EBUSY for padata_do_parallel, and it won't call aead_request_complete(). Therefore, test_aead_vec_cfg will hung at wait_for_completion(&wait->completion), which will cause hungtask. The problem comes as following: (padata_do_parallel) | rcu_read_lock_bh(); | err = -EINVAL; | (padata_replace) | pinst->flags |= PADATA_RESET; err = -EBUSY | if (pinst->flags & PADATA_RESET) | rcu_read_unlock_bh() | return err In order to resolve the problem, we replace the return err -EBUSY with -EAGAIN, which means parallel_data is changing, and the caller should call it again. v3: remove retry and just change the return err. v2: introduce padata_try_do_parallel() in pcrypt_aead_encrypt and pcrypt_aead_decrypt to solve the hungtask. Signed-off-by: Lu Jialin Signed-off-by: Guo Zihua Signed-off-by: Herbert Xu

padata: use alignment when calculating the number of worker threads

2023-03-14T09:06:44Z

For multithreaded jobs the computed chunk size is rounded up by the caller-specified alignment. However, the number of worker threads to use is computed using the minimum chunk size without taking alignment into account. A sufficiently large alignment value can result in too many worker threads being allocated for the job. Signed-off-by: Anthony Yznaga Acked-by: Daniel Jordan Signed-off-by: Herbert Xu

padata: Make kobj_type structure constant

2023-03-14T09:06:42Z

Since commit ee6d3dd4ed48 ("driver core: make kobj_type constant.") the driver core allows the usage of const struct kobj_type. Take advantage of this to constify the structure definition to prevent modification at runtime. Signed-off-by: Thomas Weißschuh Acked-by: Daniel Jordan Signed-off-by: Herbert Xu

Merge tag 'kbuild-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2022-12-19T18:33:32Z

Pull Kbuild updates from Masahiro Yamada: - Support zstd-compressed debug info - Allow W=1 builds to detect objects shared among multiple modules - Add srcrpm-pkg target to generate a source RPM package - Make the -s option detection work for future GNU Make versions - Add -Werror to KBUILD_CPPFLAGS when CONFIG_WERROR=y - Allow W=1 builds to detect -Wundef warnings in any preprocessed files - Raise the minimum supported version of binutils to 2.25 - Use $(intcmp ...) to compare integers if GNU Make >= 4.4 is used - Use $(file ...) to read a file if GNU Make >= 4.2 is used - Print error if GNU Make older than 3.82 is used - Allow modpost to detect section mismatches with Clang LTO - Include vmlinuz.efi into kernel tarballs for arm64 CONFIG_EFI_ZBOOT=y * tag 'kbuild-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits) buildtar: fix tarballs with EFI_ZBOOT enabled modpost: Include '.text.*' in TEXT_SECTIONS padata: Mark padata_work_init() as __ref kbuild: ensure Make >= 3.82 is used kbuild: refactor the prerequisites of the modpost rule kbuild: change module.order to list *.o instead of *.ko kbuild: use .NOTINTERMEDIATE for future GNU Make versions kconfig: refactor Makefile to reduce process forks kbuild: add read-file macro kbuild: do not sort after reading modules.order kbuild: add test-{ge,gt,le,lt} macros Documentation: raise minimum supported version of binutils to 2.25 kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds kbuild: move -Werror from KBUILD_CFLAGS to KBUILD_CPPFLAGS kbuild: Port silent mode detection to future gnu make. init/version.c: remove #include firmware_loader: remove #include modpost: Mark uuid_le type to be suitable only for MEI kbuild: add ability to make source rpm buildable using koji kbuild: warn objects shared among multiple modules ...