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2024-11-08bpf: Fix out-of-bounds write in trie_get_next_key()Byeonguk Jeong
[ Upstream commit 13400ac8fb80c57c2bfb12ebd35ee121ce9b4d21 ] trie_get_next_key() allocates a node stack with size trie->max_prefixlen, while it writes (trie->max_prefixlen + 1) nodes to the stack when it has full paths from the root to leaves. For example, consider a trie with max_prefixlen is 8, and the nodes with key 0x00/0, 0x00/1, 0x00/2, ... 0x00/8 inserted. Subsequent calls to trie_get_next_key with _key with .prefixlen = 8 make 9 nodes be written on the node stack with size 8. Fixes: b471f2f1de8b ("bpf: implement MAP_GET_NEXT_KEY command for LPM_TRIE map") Signed-off-by: Byeonguk Jeong <jungbu2855@gmail.com> Reviewed-by: Toke Høiland-Jørgensen <toke@kernel.org> Tested-by: Hou Tao <houtao1@huawei.com> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/Zxx384ZfdlFYnz6J@localhost.localdomain Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08cgroup: Fix potential overflow issue when checking max_depthXiu Jianfeng
[ Upstream commit 3cc4e13bb1617f6a13e5e6882465984148743cf4 ] cgroup.max.depth is the maximum allowed descent depth below the current cgroup. If the actual descent depth is equal or larger, an attempt to create a new child cgroup will fail. However due to the cgroup->max_depth is of int type and having the default value INT_MAX, the condition 'level > cgroup->max_depth' will never be satisfied, and it will cause an overflow of the level after it reaches to INT_MAX. Fix it by starting the level from 0 and using '>=' instead. It's worth mentioning that this issue is unlikely to occur in reality, as it's impossible to have a depth of INT_MAX hierarchy, but should be be avoided logically. Fixes: 1a926e0bbab8 ("cgroup: implement hierarchy limits") Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08posix-clock: posix-clock: Fix unbalanced locking in pc_clock_settime()Jinjie Ruan
[ Upstream commit 6e62807c7fbb3c758d233018caf94dfea9c65dbd ] If get_clock_desc() succeeds, it calls fget() for the clockid's fd, and get the clk->rwsem read lock, so the error path should release the lock to make the lock balance and fput the clockid's fd to make the refcount balance and release the fd related resource. However the below commit left the error path locked behind resulting in unbalanced locking. Check timespec64_valid_strict() before get_clock_desc() to fix it, because the "ts" is not changed after that. Fixes: d8794ac20a29 ("posix-clock: Fix missing timespec64 check in pc_clock_settime()") Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Acked-by: Anna-Maria Behnsen <anna-maria@linutronix.de> [pabeni@redhat.com: fixed commit message typo] Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08tracing: Consider the NULL character when validating the event lengthLeo Yan
[ Upstream commit 0b6e2e22cb23105fcb171ab92f0f7516c69c8471 ] strlen() returns a string length excluding the null byte. If the string length equals to the maximum buffer length, the buffer will have no space for the NULL terminating character. This commit checks this condition and returns failure for it. Link: https://lore.kernel.org/all/20241007144724.920954-1-leo.yan@arm.com/ Fixes: dec65d79fd26 ("tracing/probe: Check event name length correctly") Signed-off-by: Leo Yan <leo.yan@arm.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08tracing/kprobes: Fix symbol counting logic by looking at modules as wellAndrii Nakryiko
commit 926fe783c8a64b33997fec405cf1af3e61aed441 upstream. Recent changes to count number of matching symbols when creating a kprobe event failed to take into account kernel modules. As such, it breaks kprobes on kernel module symbols, by assuming there is no match. Fix this my calling module_kallsyms_on_each_symbol() in addition to kallsyms_on_each_match_symbol() to perform a proper counting. Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/ Cc: Francis Laniel <flaniel@linux.microsoft.com> Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> [ Sherry: It's a fix for previous backport, thus backport together to 5.4.y ] Signed-off-by: Sherry Yang <sherry.yang@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbolsFrancis Laniel
commit b022f0c7e404887a7c5229788fc99eff9f9a80d5 upstream. When a kprobe is attached to a function that's name is not unique (is static and shares the name with other functions in the kernel), the kprobe is attached to the first function it finds. This is a bug as the function that it is attaching to is not necessarily the one that the user wants to attach to. Instead of blindly picking a function to attach to what is ambiguous, error with EADDRNOTAVAIL to let the user know that this function is not unique, and that the user must use another unique function with an address offset to get to the function they want to attach to. Link: https://lore.kernel.org/all/20231020104250.9537-2-flaniel@linux.microsoft.com/ Cc: stable@vger.kernel.org Fixes: 413d37d1eb69 ("tracing: Add kprobe-based event tracer") Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com> Link: https://lore.kernel.org/lkml/20230819101105.b0c104ae4494a7d1f2eea742@kernel.org/ Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> [ Sherry: kselftest kprobe_non_uniq_symbol.tc failed on 5.4.y, because of missing this commit, backport it to 5.4.y. Minor conflicts due to context change, ignore context change ] Signed-off-by: Sherry Yang <sherry.yang@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08posix-clock: Fix missing timespec64 check in pc_clock_settime()Jinjie Ruan
commit d8794ac20a299b647ba9958f6d657051fc51a540 upstream. As Andrew pointed out, it will make sense that the PTP core checked timespec64 struct's tv_sec and tv_nsec range before calling ptp->info->settime64(). As the man manual of clock_settime() said, if tp.tv_sec is negative or tp.tv_nsec is outside the range [0..999,999,999], it should return EINVAL, which include dynamic clocks which handles PTP clock, and the condition is consistent with timespec64_valid(). As Thomas suggested, timespec64_valid() only check the timespec is valid, but not ensure that the time is in a valid range, so check it ahead using timespec64_valid_strict() in pc_clock_settime() and return -EINVAL if not valid. There are some drivers that use tp->tv_sec and tp->tv_nsec directly to write registers without validity checks and assume that the higher layer has checked it, which is dangerous and will benefit from this, such as hclge_ptp_settime(), igb_ptp_settime_i210(), _rcar_gen4_ptp_settime(), and some drivers can remove the checks of itself. Cc: stable@vger.kernel.org Fixes: 0606f422b453 ("posix clocks: Introduce dynamic clocks") Acked-by: Richard Cochran <richardcochran@gmail.com> Suggested-by: Andrew Lunn <andrew@lunn.ch> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20241009072302.1754567-2-ruanjinjie@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08resource: fix region_intersects() vs add_memory_driver_managed()Huang Ying
commit b4afe4183ec77f230851ea139d91e5cf2644c68b upstream. On a system with CXL memory, the resource tree (/proc/iomem) related to CXL memory may look like something as follows. 490000000-50fffffff : CXL Window 0 490000000-50fffffff : region0 490000000-50fffffff : dax0.0 490000000-50fffffff : System RAM (kmem) Because drivers/dax/kmem.c calls add_memory_driver_managed() during onlining CXL memory, which makes "System RAM (kmem)" a descendant of "CXL Window X". This confuses region_intersects(), which expects all "System RAM" resources to be at the top level of iomem_resource. This can lead to bugs. For example, when the following command line is executed to write some memory in CXL memory range via /dev/mem, $ dd if=data of=/dev/mem bs=$((1 << 10)) seek=$((0x490000000 >> 10)) count=1 dd: error writing '/dev/mem': Bad address 1+0 records in 0+0 records out 0 bytes copied, 0.0283507 s, 0.0 kB/s the command fails as expected. However, the error code is wrong. It should be "Operation not permitted" instead of "Bad address". More seriously, the /dev/mem permission checking in devmem_is_allowed() passes incorrectly. Although the accessing is prevented later because ioremap() isn't allowed to map system RAM, it is a potential security issue. During command executing, the following warning is reported in the kernel log for calling ioremap() on system RAM. ioremap on RAM at 0x0000000490000000 - 0x0000000490000fff WARNING: CPU: 2 PID: 416 at arch/x86/mm/ioremap.c:216 __ioremap_caller.constprop.0+0x131/0x35d Call Trace: memremap+0xcb/0x184 xlate_dev_mem_ptr+0x25/0x2f write_mem+0x94/0xfb vfs_write+0x128/0x26d ksys_write+0xac/0xfe do_syscall_64+0x9a/0xfd entry_SYSCALL_64_after_hwframe+0x4b/0x53 The details of command execution process are as follows. In the above resource tree, "System RAM" is a descendant of "CXL Window 0" instead of a top level resource. So, region_intersects() will report no System RAM resources in the CXL memory region incorrectly, because it only checks the top level resources. Consequently, devmem_is_allowed() will return 1 (allow access via /dev/mem) for CXL memory region incorrectly. Fortunately, ioremap() doesn't allow to map System RAM and reject the access. So, region_intersects() needs to be fixed to work correctly with the resource tree with "System RAM" not at top level as above. To fix it, if we found a unmatched resource in the top level, we will continue to search matched resources in its descendant resources. So, we will not miss any matched resources in resource tree anymore. In the new implementation, an example resource tree |------------- "CXL Window 0" ------------| |-- "System RAM" --| will behave similar as the following fake resource tree for region_intersects(, IORESOURCE_SYSTEM_RAM, ), |-- "System RAM" --||-- "CXL Window 0a" --| Where "CXL Window 0a" is part of the original "CXL Window 0" that isn't covered by "System RAM". Link: https://lkml.kernel.org/r/20240906030713.204292-2-ying.huang@intel.com Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jonathan Cameron <jonathan.cameron@huawei.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08lockdep: fix deadlock issue between lockdep and rcuZhiguo Niu
commit a6f88ac32c6e63e69c595bfae220d8641704c9b7 upstream. There is a deadlock scenario between lockdep and rcu when rcu nocb feature is enabled, just as following call stack: rcuop/x -000|queued_spin_lock_slowpath(lock = 0xFFFFFF817F2A8A80, val = ?) -001|queued_spin_lock(inline) // try to hold nocb_gp_lock -001|do_raw_spin_lock(lock = 0xFFFFFF817F2A8A80) -002|__raw_spin_lock_irqsave(inline) -002|_raw_spin_lock_irqsave(lock = 0xFFFFFF817F2A8A80) -003|wake_nocb_gp_defer(inline) -003|__call_rcu_nocb_wake(rdp = 0xFFFFFF817F30B680) -004|__call_rcu_common(inline) -004|call_rcu(head = 0xFFFFFFC082EECC28, func = ?) -005|call_rcu_zapped(inline) -005|free_zapped_rcu(ch = ?)// hold graph lock -006|rcu_do_batch(rdp = 0xFFFFFF817F245680) -007|nocb_cb_wait(inline) -007|rcu_nocb_cb_kthread(arg = 0xFFFFFF817F245680) -008|kthread(_create = 0xFFFFFF80803122C0) -009|ret_from_fork(asm) rcuop/y -000|queued_spin_lock_slowpath(lock = 0xFFFFFFC08291BBC8, val = 0) -001|queued_spin_lock() -001|lockdep_lock() -001|graph_lock() // try to hold graph lock -002|lookup_chain_cache_add() -002|validate_chain() -003|lock_acquire -004|_raw_spin_lock_irqsave(lock = 0xFFFFFF817F211D80) -005|lock_timer_base(inline) -006|mod_timer(inline) -006|wake_nocb_gp_defer(inline)// hold nocb_gp_lock -006|__call_rcu_nocb_wake(rdp = 0xFFFFFF817F2A8680) -007|__call_rcu_common(inline) -007|call_rcu(head = 0xFFFFFFC0822E0B58, func = ?) -008|call_rcu_hurry(inline) -008|rcu_sync_call(inline) -008|rcu_sync_func(rhp = 0xFFFFFFC0822E0B58) -009|rcu_do_batch(rdp = 0xFFFFFF817F266680) -010|nocb_cb_wait(inline) -010|rcu_nocb_cb_kthread(arg = 0xFFFFFF817F266680) -011|kthread(_create = 0xFFFFFF8080363740) -012|ret_from_fork(asm) rcuop/x and rcuop/y are rcu nocb threads with the same nocb gp thread. This patch release the graph lock before lockdep call_rcu. Fixes: a0b0fd53e1e6 ("locking/lockdep: Free lock classes that are no longer in use") Cc: stable@vger.kernel.org Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Waiman Long <longman@redhat.com> Cc: Carlos Llamas <cmllamas@google.com> Cc: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Reviewed-by: Waiman Long <longman@redhat.com> Reviewed-by: Carlos Llamas <cmllamas@google.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Carlos Llamas <cmllamas@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20240620225436.3127927-1-cmllamas@google.com Signed-off-by: Carlos Llamas <cmllamas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08locking/lockdep: Avoid potential access of invalid memory in lock_classWaiman Long
commit 61cc4534b6550997c97a03759ab46b29d44c0017 upstream. It was found that reading /proc/lockdep after a lockdep splat may potentially cause an access to freed memory if lockdep_unregister_key() is called after the splat but before access to /proc/lockdep [1]. This is due to the fact that graph_lock() call in lockdep_unregister_key() fails after the clearing of debug_locks by the splat process. After lockdep_unregister_key() is called, the lock_name may be freed but the corresponding lock_class structure still have a reference to it. That invalid memory pointer will then be accessed when /proc/lockdep is read by a user and a use-after-free (UAF) error will be reported if KASAN is enabled. To fix this problem, lockdep_unregister_key() is now modified to always search for a matching key irrespective of the debug_locks state and zap the corresponding lock class if a matching one is found. [1] https://lore.kernel.org/lkml/77f05c15-81b6-bddd-9650-80d5f23fe330@i-love.sakura.ne.jp/ Fixes: 8b39adbee805 ("locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' again") Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lkml.kernel.org/r/20220103023558.1377055-1-longman@redhat.com Signed-off-by: Carlos Llamas <cmllamas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08locking/lockdep: Rework lockdep_lockPeter Zijlstra
commit 248efb2158f1e23750728e92ad9db3ab60c14485 upstream. A few sites want to assert we own the graph_lock/lockdep_lock, provide a more conventional lock interface for it with a number of trivial debug checks. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200313102107.GX12561@hirez.programming.kicks-ass.net Signed-off-by: Carlos Llamas <cmllamas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08locking/lockdep: Fix bad recursion patternPeter Zijlstra
commit 10476e6304222ced7df9b3d5fb0a043b3c2a1ad8 upstream. There were two patterns for lockdep_recursion: Pattern-A: if (current->lockdep_recursion) return current->lockdep_recursion = 1; /* do stuff */ current->lockdep_recursion = 0; Pattern-B: current->lockdep_recursion++; /* do stuff */ current->lockdep_recursion--; But a third pattern has emerged: Pattern-C: current->lockdep_recursion = 1; /* do stuff */ current->lockdep_recursion = 0; And while this isn't broken per-se, it is highly dangerous because it doesn't nest properly. Get rid of all Pattern-C instances and shore up Pattern-A with a warning. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200313093325.GW12561@hirez.programming.kicks-ass.net Signed-off-by: Carlos Llamas <cmllamas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08bpf: Check percpu map value size firstTao Chen
[ Upstream commit 1d244784be6b01162b732a5a7d637dfc024c3203 ] Percpu map is often used, but the map value size limit often ignored, like issue: https://github.com/iovisor/bcc/issues/2519. Actually, percpu map value size is bound by PCPU_MIN_UNIT_SIZE, so we can check the value size whether it exceeds PCPU_MIN_UNIT_SIZE first, like percpu map of local_storage. Maybe the error message seems clearer compared with "cannot allocate memory". Signed-off-by: Jinke Han <jinkehan@didiglobal.com> Signed-off-by: Tao Chen <chen.dylane@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240910144111.1464912-2-chen.dylane@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08tracing: Have saved_cmdlines arrays all in one allocationSteven Rostedt (Google)
[ Upstream commit 0b18c852cc6fb8284ac0ab97e3e840974a6a8a64 ] The saved_cmdlines have three arrays for mapping PIDs to COMMs: - map_pid_to_cmdline[] - map_cmdline_to_pid[] - saved_cmdlines The map_pid_to_cmdline[] is PID_MAX_DEFAULT in size and holds the index into the other arrays. The map_cmdline_to_pid[] is a mapping back to the full pid as it can be larger than PID_MAX_DEFAULT. And the saved_cmdlines[] just holds the COMMs associated to the pids. Currently the map_pid_to_cmdline[] and saved_cmdlines[] are allocated together (in reality the saved_cmdlines is just in the memory of the rounding of the allocation of the structure as it is always allocated in powers of two). The map_cmdline_to_pid[] array is allocated separately. Since the rounding to a power of two is rather large (it allows for 8000 elements in saved_cmdlines), also include the map_cmdline_to_pid[] array. (This drops it to 6000 by default, which is still plenty for most use cases). This saves even more memory as the map_cmdline_to_pid[] array doesn't need to be allocated. Link: https://lore.kernel.org/linux-trace-kernel/20240212174011.068211d9@gandalf.local.home/ Link: https://lore.kernel.org/linux-trace-kernel/20240220140703.182330529@goodmis.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Mete Durlu <meted@linux.ibm.com> Fixes: 44dc5c41b5b1 ("tracing: Fix wasted memory in saved_cmdlines logic") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08tracing: Remove precision vsnprintf() check from print eventSteven Rostedt (Google)
[ Upstream commit 5efd3e2aef91d2d812290dcb25b2058e6f3f532c ] This reverts 60be76eeabb3d ("tracing: Add size check when printing trace_marker output"). The only reason the precision check was added was because of a bug that miscalculated the write size of the string into the ring buffer and it truncated it removing the terminating nul byte. On reading the trace it crashed the kernel. But this was due to the bug in the code that happened during development and should never happen in practice. If anything, the precision can hide bugs where the string in the ring buffer isn't nul terminated and it will not be checked. Link: https://lore.kernel.org/all/C7E7AF1A-D30F-4D18-B8E5-AF1EF58004F5@linux.ibm.com/ Link: https://lore.kernel.org/linux-trace-kernel/20240227125706.04279ac2@gandalf.local.home Link: https://lore.kernel.org/all/20240302111244.3a1674be@gandalf.local.home/ Link: https://lore.kernel.org/linux-trace-kernel/20240304174341.2a561d9f@gandalf.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 60be76eeabb3d ("tracing: Add size check when printing trace_marker output") Reported-by: Sachin Sant <sachinp@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08uprobes: fix kernel info leak via "[uprobes]" vmaOleg Nesterov
commit 34820304cc2cd1804ee1f8f3504ec77813d29c8e upstream. xol_add_vma() maps the uninitialized page allocated by __create_xol_area() into userspace. On some architectures (x86) this memory is readable even without VM_READ, VM_EXEC results in the same pgprot_t as VM_EXEC|VM_READ, although this doesn't really matter, debugger can read this memory anyway. Link: https://lore.kernel.org/all/20240929162047.GA12611@redhat.com/ Reported-by: Will Deacon <will@kernel.org> Fixes: d4b3b6384f98 ("uprobes/core: Allocate XOL slots for uprobes use") Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08perf/core: Fix small negative period being ignoredLuo Gengkun
commit 62c0b1061593d7012292f781f11145b2d46f43ab upstream. In perf_adjust_period, we will first calculate period, and then use this period to calculate delta. However, when delta is less than 0, there will be a deviation compared to when delta is greater than or equal to 0. For example, when delta is in the range of [-14,-1], the range of delta = delta + 7 is between [-7,6], so the final value of delta/8 is 0. Therefore, the impact of -1 and -2 will be ignored. This is unacceptable when the target period is very short, because we will lose a lot of samples. Here are some tests and analyzes: before: # perf record -e cs -F 1000 ./a.out [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.022 MB perf.data (518 samples) ] # perf script ... a.out 396 257.956048: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.957891: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.959730: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.961545: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.963355: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.965163: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.966973: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.968785: 23 cs: ffffffff81f4eeec schedul> a.out 396 257.970593: 23 cs: ffffffff81f4eeec schedul> ... after: # perf record -e cs -F 1000 ./a.out [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.058 MB perf.data (1466 samples) ] # perf script ... a.out 395 59.338813: 11 cs: ffffffff81f4eeec schedul> a.out 395 59.339707: 12 cs: ffffffff81f4eeec schedul> a.out 395 59.340682: 13 cs: ffffffff81f4eeec schedul> a.out 395 59.341751: 13 cs: ffffffff81f4eeec schedul> a.out 395 59.342799: 12 cs: ffffffff81f4eeec schedul> a.out 395 59.343765: 11 cs: ffffffff81f4eeec schedul> a.out 395 59.344651: 11 cs: ffffffff81f4eeec schedul> a.out 395 59.345539: 12 cs: ffffffff81f4eeec schedul> a.out 395 59.346502: 13 cs: ffffffff81f4eeec schedul> ... test.c int main() { for (int i = 0; i < 20000; i++) usleep(10); return 0; } # time ./a.out real 0m1.583s user 0m0.040s sys 0m0.298s The above results were tested on x86-64 qemu with KVM enabled using test.c as test program. Ideally, we should have around 1500 samples, but the previous algorithm had only about 500, whereas the modified algorithm now has about 1400. Further more, the new version shows 1 sample per 0.001s, while the previous one is 1 sample per 0.002s.This indicates that the new algorithm is more sensitive to small negative values compared to old algorithm. Fixes: bd2b5b12849a ("perf_counter: More aggressive frequency adjustment") Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20240831074316.2106159-2-luogengkun@huaweicloud.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08signal: Replace BUG_ON()sThomas Gleixner
[ Upstream commit 7f8af7bac5380f2d95a63a6f19964e22437166e1 ] These really can be handled gracefully without killing the machine. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08bpf: Fix bpf_strtol and bpf_strtoul helpers for 32bitDaniel Borkmann
[ Upstream commit cfe69c50b05510b24e26ccb427c7cc70beafd6c1 ] The bpf_strtol() and bpf_strtoul() helpers are currently broken on 32bit: The argument type ARG_PTR_TO_LONG is BPF-side "long", not kernel-side "long" and therefore always considered fixed 64bit no matter if 64 or 32bit underlying architecture. This contract breaks in case of the two mentioned helpers since their BPF_CALL definition for the helpers was added with {unsigned,}long *res. Meaning, the transition from BPF-side "long" (BPF program) to kernel-side "long" (BPF helper) breaks here. Both helpers call __bpf_strtoll() with "long long" correctly, but later assigning the result into 32-bit "*(long *)" on 32bit architectures. From a BPF program point of view, this means upper bits will be seen as uninitialised. Therefore, fix both BPF_CALL signatures to {s,u}64 types to fix this situation. Now, changing also uapi/bpf.h helper documentation which generates bpf_helper_defs.h for BPF programs is tricky: Changing signatures there to __{s,u}64 would trigger compiler warnings (incompatible pointer types passing 'long *' to parameter of type '__s64 *' (aka 'long long *')) for existing BPF programs. Leaving the signatures as-is would be fine as from BPF program point of view it is still BPF-side "long" and thus equivalent to __{s,u}64 on 64 or 32bit underlying architectures. Note that bpf_strtol() and bpf_strtoul() are the only helpers with this issue. Fixes: d7a4cb9b6705 ("bpf: Introduce bpf_strtol and bpf_strtoul helpers") Reported-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/481fcec8-c12c-9abb-8ecb-76c71c009959@iogearbox.net Link: https://lore.kernel.org/r/20240913191754.13290-1-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08kthread: fix task state in kthread worker if being frozenChen Yu
[ Upstream commit e16c7b07784f3fb03025939c4590b9a7c64970a7 ] When analyzing a kernel waring message, Peter pointed out that there is a race condition when the kworker is being frozen and falls into try_to_freeze() with TASK_INTERRUPTIBLE, which could trigger a might_sleep() warning in try_to_freeze(). Although the root cause is not related to freeze()[1], it is still worthy to fix this issue ahead. One possible race scenario: CPU 0 CPU 1 ----- ----- // kthread_worker_fn set_current_state(TASK_INTERRUPTIBLE); suspend_freeze_processes() freeze_processes static_branch_inc(&freezer_active); freeze_kernel_threads pm_nosig_freezing = true; if (work) { //false __set_current_state(TASK_RUNNING); } else if (!freezing(current)) //false, been frozen freezing(): if (static_branch_unlikely(&freezer_active)) if (pm_nosig_freezing) return true; schedule() } // state is still TASK_INTERRUPTIBLE try_to_freeze() might_sleep() <--- warning Fix this by explicitly set the TASK_RUNNING before entering try_to_freeze(). Link: https://lore.kernel.org/lkml/Zs2ZoAcUsZMX2B%2FI@chenyu5-mobl2/ [1] Link: https://lkml.kernel.org/r/20240827112308.181081-1-yu.c.chen@intel.com Fixes: b56c0d8937e6 ("kthread: implement kthread_worker") Signed-off-by: Chen Yu <yu.c.chen@intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: David Gow <davidgow@google.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Mickaël Salaün <mic@digikod.net> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08kthread: add kthread_work tracepointsRob Clark
[ Upstream commit f630c7c6f10546ebff15c3a856e7949feb7a2372 ] While migrating some code from wq to kthread_worker, I found that I missed the execute_start/end tracepoints. So add similar tracepoints for kthread_work. And for completeness, queue_work tracepoint (although this one differs slightly from the matching workqueue tracepoint). Link: https://lkml.kernel.org/r/20201010180323.126634-1-robdclark@gmail.com Signed-off-by: Rob Clark <robdclark@chromium.org> Cc: Rob Clark <robdclark@chromium.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Phil Auld <pauld@redhat.com> Cc: Valentin Schneider <valentin.schneider@arm.com> Cc: Thara Gopinath <thara.gopinath@linaro.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Vincent Donnefort <vincent.donnefort@arm.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Ilias Stamatis <stamatis.iliass@gmail.com> Cc: Liang Chen <cl@rock-chips.com> Cc: Ben Dooks <ben.dooks@codethink.co.uk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: "J. Bruce Fields" <bfields@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Stable-dep-of: e16c7b07784f ("kthread: fix task state in kthread worker if being frozen") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08bpf: Fix DEVMAP_HASH overflow check on 32-bit archesToke Høiland-Jørgensen
commit 281d464a34f540de166cee74b723e97ac2515ec3 upstream. The devmap code allocates a number hash buckets equal to the next power of two of the max_entries value provided when creating the map. When rounding up to the next power of two, the 32-bit variable storing the number of buckets can overflow, and the code checks for overflow by checking if the truncated 32-bit value is equal to 0. However, on 32-bit arches the rounding up itself can overflow mid-way through, because it ends up doing a left-shift of 32 bits on an unsigned long value. If the size of an unsigned long is four bytes, this is undefined behaviour, so there is no guarantee that we'll end up with a nice and tidy 0-value at the end. Syzbot managed to turn this into a crash on arm32 by creating a DEVMAP_HASH with max_entries > 0x80000000 and then trying to update it. Fix this by moving the overflow check to before the rounding up operation. Fixes: 6f9d451ab1a3 ("xdp: Add devmap_hash map type for looking up devices by hashed index") Link: https://lore.kernel.org/r/000000000000ed666a0611af6818@google.com Reported-and-tested-by: syzbot+8cd36f6b65f3cafd400a@syzkaller.appspotmail.com Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Message-ID: <20240307120340.99577-2-toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-12rtmutex: Drop rt_mutex::wait_lock before schedulingRoland Xu
commit d33d26036a0274b472299d7dcdaa5fb34329f91b upstream. rt_mutex_handle_deadlock() is called with rt_mutex::wait_lock held. In the good case it returns with the lock held and in the deadlock case it emits a warning and goes into an endless scheduling loop with the lock held, which triggers the 'scheduling in atomic' warning. Unlock rt_mutex::wait_lock in the dead lock case before issuing the warning and dropping into the schedule for ever loop. [ tglx: Moved unlock before the WARN(), removed the pointless comment, massaged changelog, added Fixes tag ] Fixes: 3d5c9340d194 ("rtmutex: Handle deadlock detection smarter") Signed-off-by: Roland Xu <mu001999@outlook.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/ME0P300MB063599BEF0743B8FA339C2CECC802@ME0P300MB0635.AUSP300.PROD.OUTLOOK.COM Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-12tracing: Avoid possible softlockup in tracing_iter_reset()Zheng Yejian
[ Upstream commit 49aa8a1f4d6800721c7971ed383078257f12e8f9 ] In __tracing_open(), when max latency tracers took place on the cpu, the time start of its buffer would be updated, then event entries with timestamps being earlier than start of the buffer would be skipped (see tracing_iter_reset()). Softlockup will occur if the kernel is non-preemptible and too many entries were skipped in the loop that reset every cpu buffer, so add cond_resched() to avoid it. Cc: stable@vger.kernel.org Fixes: 2f26ebd549b9a ("tracing: use timestamp to determine start of latency traces") Link: https://lore.kernel.org/20240827124654.3817443-1-zhengyejian@huaweicloud.com Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Zheng Yejian <zhengyejian@huaweicloud.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-12ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance()Steven Rostedt (VMware)
[ Upstream commit bc1a72afdc4a91844928831cac85731566e03bc6 ] When the ring buffer was first created, the iterator followed the normal producer/consumer operations where it had both a peek() operation, that just returned the event at the current location, and a read(), that would return the event at the current location and also increment the iterator such that the next peek() or read() will return the next event. The only use of the ring_buffer_read() is currently to move the iterator to the next location and nothing now actually reads the event it returns. Rename this function to its actual use case to ring_buffer_iter_advance(), which also adds the "iter" part to the name, which is more meaningful. As the timestamp returned by ring_buffer_read() was never used, there's no reason that this new version should bother having returning it. It will also become a void function. Link: http://lkml.kernel.org/r/20200317213416.018928618@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Stable-dep-of: 49aa8a1f4d68 ("tracing: Avoid possible softlockup in tracing_iter_reset()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-12uprobes: Use kzalloc to allocate xol areaSven Schnelle
commit e240b0fde52f33670d1336697c22d90a4fe33c84 upstream. To prevent unitialized members, use kzalloc to allocate the xol area. Fixes: b059a453b1cf1 ("x86/vdso: Add mremap hook to vm_special_mapping") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20240903102313.3402529-1-svens@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-12smp: Add missing destroy_work_on_stack() call in smp_call_on_cpu()Zqiang
[ Upstream commit 77aeb1b685f9db73d276bad4bb30d48505a6fd23 ] For CONFIG_DEBUG_OBJECTS_WORK=y kernels sscs.work defined by INIT_WORK_ONSTACK() is initialized by debug_object_init_on_stack() for the debug check in __init_work() to work correctly. But this lacks the counterpart to remove the tracked object from debug objects again, which will cause a debug object warning once the stack is freed. Add the missing destroy_work_on_stack() invocation to cure that. [ tglx: Massaged changelog ] Signed-off-by: Zqiang <qiang.zhang1211@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240704065213.13559-1-qiang.zhang1211@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-12cgroup: Protect css->cgroup write under css_set_lockWaiman Long
[ Upstream commit 57b56d16800e8961278ecff0dc755d46c4575092 ] The writing of css->cgroup associated with the cgroup root in rebind_subsystems() is currently protected only by cgroup_mutex. However, the reading of css->cgroup in both proc_cpuset_show() and proc_cgroup_show() is protected just by css_set_lock. That makes the readers susceptible to racing problems like data tearing or caching. It is also a problem that can be reported by KCSAN. This can be fixed by using READ_ONCE() and WRITE_ONCE() to access css->cgroup. Alternatively, the writing of css->cgroup can be moved under css_set_lock as well which is done by this patch. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-04cgroup/cpuset: Prevent UAF in proc_cpuset_show()Chen Ridong
commit 1be59c97c83ccd67a519d8a49486b3a8a73ca28a upstream. An UAF can happen when /proc/cpuset is read as reported in [1]. This can be reproduced by the following methods: 1.add an mdelay(1000) before acquiring the cgroup_lock In the cgroup_path_ns function. 2.$cat /proc/<pid>/cpuset repeatly. 3.$mount -t cgroup -o cpuset cpuset /sys/fs/cgroup/cpuset/ $umount /sys/fs/cgroup/cpuset/ repeatly. The race that cause this bug can be shown as below: (umount) | (cat /proc/<pid>/cpuset) css_release | proc_cpuset_show css_release_work_fn | css = task_get_css(tsk, cpuset_cgrp_id); css_free_rwork_fn | cgroup_path_ns(css->cgroup, ...); cgroup_destroy_root | mutex_lock(&cgroup_mutex); rebind_subsystems | cgroup_free_root | | // cgrp was freed, UAF | cgroup_path_ns_locked(cgrp,..); When the cpuset is initialized, the root node top_cpuset.css.cgrp will point to &cgrp_dfl_root.cgrp. In cgroup v1, the mount operation will allocate cgroup_root, and top_cpuset.css.cgrp will point to the allocated &cgroup_root.cgrp. When the umount operation is executed, top_cpuset.css.cgrp will be rebound to &cgrp_dfl_root.cgrp. The problem is that when rebinding to cgrp_dfl_root, there are cases where the cgroup_root allocated by setting up the root for cgroup v1 is cached. This could lead to a Use-After-Free (UAF) if it is subsequently freed. The descendant cgroups of cgroup v1 can only be freed after the css is released. However, the css of the root will never be released, yet the cgroup_root should be freed when it is unmounted. This means that obtaining a reference to the css of the root does not guarantee that css.cgrp->root will not be freed. Fix this problem by using rcu_read_lock in proc_cpuset_show(). As cgroup_root is kfree_rcu after commit d23b5c577715 ("cgroup: Make operations on the cgroup root_list RCU safe"), css->cgroup won't be freed during the critical section. To call cgroup_path_ns_locked, css_set_lock is needed, so it is safe to replace task_get_css with task_css. [1] https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd Fixes: a79a908fd2b0 ("cgroup: introduce cgroup namespaces") Signed-off-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Shivani Agarwal <shivani.agarwal@broadcom.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-04hrtimer: Prevent queuing of hrtimer without a function callbackPhil Chang
[ Upstream commit 5a830bbce3af16833fe0092dec47b6dd30279825 ] The hrtimer function callback must not be NULL. It has to be specified by the call side but it is not validated by the hrtimer code. When a hrtimer is queued without a function callback, the kernel crashes with a null pointer dereference when trying to execute the callback in __run_hrtimer(). Introduce a validation before queuing the hrtimer in hrtimer_start_range_ns(). [anna-maria: Rephrase commit message] Signed-off-by: Phil Chang <phil.chang@mediatek.com> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19tracing: Fix overflow in get_free_elt()Tze-nan Wu
commit bcf86c01ca4676316557dd482c8416ece8c2e143 upstream. "tracing_map->next_elt" in get_free_elt() is at risk of overflowing. Once it overflows, new elements can still be inserted into the tracing_map even though the maximum number of elements (`max_elts`) has been reached. Continuing to insert elements after the overflow could result in the tracing_map containing "tracing_map->max_size" elements, leaving no empty entries. If any attempt is made to insert an element into a full tracing_map using `__tracing_map_insert()`, it will cause an infinite loop with preemption disabled, leading to a CPU hang problem. Fix this by preventing any further increments to "tracing_map->next_elt" once it reaches "tracing_map->max_elt". Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 08d43a5fa063e ("tracing: Add lock-free tracing_map") Co-developed-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com> Link: https://lore.kernel.org/20240805055922.6277-1-Tze-nan.Wu@mediatek.com Signed-off-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com> Signed-off-by: Tze-nan Wu <Tze-nan.Wu@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19genirq/irqdesc: Honor caller provided affinity in alloc_desc()Shay Drory
commit edbbaae42a56f9a2b39c52ef2504dfb3fb0a7858 upstream. Currently, whenever a caller is providing an affinity hint for an interrupt, the allocation code uses it to calculate the node and copies the cpumask into irq_desc::affinity. If the affinity for the interrupt is not marked 'managed' then the startup of the interrupt ignores irq_desc::affinity and uses the system default affinity mask. Prevent this by setting the IRQD_AFFINITY_SET flag for the interrupt in the allocator, which causes irq_setup_affinity() to use irq_desc::affinity on interrupt startup if the mask contains an online CPU. [ tglx: Massaged changelog ] Fixes: 45ddcecbfa94 ("genirq: Use affinity hint in irqdesc allocation") Signed-off-by: Shay Drory <shayd@nvidia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/all/20240806072044.837827-1-shayd@nvidia.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19ntp: Safeguard against time_constant overflowJustin Stitt
commit 06c03c8edce333b9ad9c6b207d93d3a5ae7c10c0 upstream. Using syzkaller with the recently reintroduced signed integer overflow sanitizer produces this UBSAN report: UBSAN: signed-integer-overflow in ../kernel/time/ntp.c:738:18 9223372036854775806 + 4 cannot be represented in type 'long' Call Trace: handle_overflow+0x171/0x1b0 __do_adjtimex+0x1236/0x1440 do_adjtimex+0x2be/0x740 The user supplied time_constant value is incremented by four and then clamped to the operating range. Before commit eea83d896e31 ("ntp: NTP4 user space bits update") the user supplied value was sanity checked to be in the operating range. That change removed the sanity check and relied on clamping after incrementing which does not work correctly when the user supplied value is in the overflow zone of the '+ 4' operation. The operation requires CAP_SYS_TIME and the side effect of the overflow is NTP getting out of sync. Similar to the fixups for time_maxerror and time_esterror, clamp the user space supplied value to the operating range. [ tglx: Switch to clamping ] Fixes: eea83d896e31 ("ntp: NTP4 user space bits update") Signed-off-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Miroslav Lichvar <mlichvar@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240517-b4-sio-ntp-c-v2-1-f3a80096f36f@google.com Closes: https://github.com/KSPP/linux/issues/352 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19ntp: Clamp maxerror and esterror to operating rangeJustin Stitt
[ Upstream commit 87d571d6fb77ec342a985afa8744bb9bb75b3622 ] Using syzkaller alongside the newly reintroduced signed integer overflow sanitizer spits out this report: UBSAN: signed-integer-overflow in ../kernel/time/ntp.c:461:16 9223372036854775807 + 500 cannot be represented in type 'long' Call Trace: handle_overflow+0x171/0x1b0 second_overflow+0x2d6/0x500 accumulate_nsecs_to_secs+0x60/0x160 timekeeping_advance+0x1fe/0x890 update_wall_time+0x10/0x30 time_maxerror is unconditionally incremented and the result is checked against NTP_PHASE_LIMIT, but the increment itself can overflow, resulting in wrap-around to negative space. Before commit eea83d896e31 ("ntp: NTP4 user space bits update") the user supplied value was sanity checked to be in the operating range. That change removed the sanity check and relied on clamping in handle_overflow() which does not work correctly when the user supplied value is in the overflow zone of the '+ 500' operation. The operation requires CAP_SYS_TIME and the side effect of the overflow is NTP getting out of sync. Miroslav confirmed that the input value should be clamped to the operating range and the same applies to time_esterror. The latter is not used by the kernel, but the value still should be in the operating range as it was before the sanity check got removed. Clamp them to the operating range. [ tglx: Changed it to clamping and included time_esterror ] Fixes: eea83d896e31 ("ntp: NTP4 user space bits update") Signed-off-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Miroslav Lichvar <mlichvar@redhat.com> Link: https://lore.kernel.org/all/20240517-b4-sio-ntp-usec-v2-1-d539180f2b79@google.com Closes: https://github.com/KSPP/linux/issues/354 Signed-off-by: Sasha Levin <sashal@kernel.org> [ cast things to long long to fix compiler warnings - gregkh ] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19tick/broadcast: Move per CPU pointer access into the atomic sectionThomas Gleixner
commit 6881e75237a84093d0986f56223db3724619f26e upstream. The recent fix for making the take over of the broadcast timer more reliable retrieves a per CPU pointer in preemptible context. This went unnoticed as compilers hoist the access into the non-preemptible region where the pointer is actually used. But of course it's valid that the compiler keeps it at the place where the code puts it which rightfully triggers: BUG: using smp_processor_id() in preemptible [00000000] code: caller is hotplug_cpu__broadcast_tick_pull+0x1c/0xc0 Move it to the actual usage site which is in a non-preemptible region. Fixes: f7d43dd206e7 ("tick/broadcast: Make takeover of broadcast hrtimer reliable") Reported-by: David Wang <00107082@163.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Yu Liao <liaoyu15@huawei.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/87ttg56ers.ffs@tglx Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19genirq: Allow irq_chip registration functions to take a const irq_chipMarc Zyngier
[ Upstream commit 393e1280f765661cf39785e967676a4e57324126 ] In order to let a const irqchip be fed to the irqchip layer, adjust the various prototypes. An extra cast in irq_set_chip()() is required to avoid a warning. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20220209162607.1118325-3-maz@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19genirq: Allow the PM device to originate from irq domainMarc Zyngier
[ Upstream commit 1f8863bfb5ca500ea1c7669b16b1931ba27fce20 ] As a preparation to moving the reference to the device used for runtime power management, add a new 'dev' field to the irqdomain structure for that exact purpose. The irq_chip_pm_{get,put}() helpers are made aware of the dual location via a new private helper. No functional change intended. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Bartosz Golaszewski <brgl@bgdev.pl> Link: https://lore.kernel.org/r/20220201120310.878267-2-maz@kernel.org Stable-dep-of: 33b1c47d1fc0 ("irqchip/imx-irqsteer: Handle runtime power management correctly") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19dma: fix call order in dmam_free_coherentLance Richardson
[ Upstream commit 28e8b7406d3a1f5329a03aa25a43aa28e087cb20 ] dmam_free_coherent() frees a DMA allocation, which makes the freed vaddr available for reuse, then calls devres_destroy() to remove and free the data structure used to track the DMA allocation. Between the two calls, it is possible for a concurrent task to make an allocation with the same vaddr and add it to the devres list. If this happens, there will be two entries in the devres list with the same vaddr and devres_destroy() can free the wrong entry, triggering the WARN_ON() in dmam_match. Fix by destroying the devres entry before freeing the DMA allocation. Tested: kokonut //net/encryption http://sponge2/b9145fe6-0f72-4325-ac2f-a84d81075b03 Fixes: 9ac7849e35f7 ("devres: device resource management") Signed-off-by: Lance Richardson <rlance@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19kdb: Use the passed prompt in kdb_position_cursor()Douglas Anderson
[ Upstream commit e2e821095949cde46256034975a90f88626a2a73 ] The function kdb_position_cursor() takes in a "prompt" parameter but never uses it. This doesn't _really_ matter since all current callers of the function pass the same value and it's a global variable, but it's a bit ugly. Let's clean it up. Found by code inspection. This patch is expected to functionally be a no-op. Fixes: 09b35989421d ("kdb: Use format-strings rather than '\0' injection in kdb_read()") Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20240528071144.1.I0feb49839c6b6f4f2c4bf34764f5e95de3f55a66@changeid Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19kdb: address -Wformat-security warningsArnd Bergmann
[ Upstream commit 70867efacf4370b6c7cdfc7a5b11300e9ef7de64 ] When -Wformat-security is not disabled, using a string pointer as a format causes a warning: kernel/debug/kdb/kdb_io.c: In function 'kdb_read': kernel/debug/kdb/kdb_io.c:365:36: error: format not a string literal and no format arguments [-Werror=format-security] 365 | kdb_printf(kdb_prompt_str); | ^~~~~~~~~~~~~~ kernel/debug/kdb/kdb_io.c: In function 'kdb_getstr': kernel/debug/kdb/kdb_io.c:456:20: error: format not a string literal and no format arguments [-Werror=format-security] 456 | kdb_printf(kdb_prompt_str); | ^~~~~~~~~~~~~~ Use an explcit "%s" format instead. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 5d5314d6795f ("kdb: core for kgdb back end (1 of 2)") Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20240528121154.3662553-1-arnd@kernel.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19watchdog/perf: properly initialize the turbo mode timestamp and rearm counterThomas Gleixner
commit f944ffcbc2e1c759764850261670586ddf3bdabb upstream. For systems on which the performance counter can expire early due to turbo modes the watchdog handler has a safety net in place which validates that since the last watchdog event there has at least 4/5th of the watchdog period elapsed. This works reliably only after the first watchdog event because the per CPU variable which holds the timestamp of the last event is never initialized. So a first spurious event will validate against a timestamp of 0 which results in a delta which is likely to be way over the 4/5 threshold of the period. As this might happen before the first watchdog hrtimer event increments the watchdog counter, this can lead to false positives. Fix this by initializing the timestamp before enabling the hardware event. Reset the rearm counter as well, as that might be non zero after the watchdog was disabled and reenabled. Link: https://lkml.kernel.org/r/87frsfu15a.ffs@tglx Fixes: 7edaeb6841df ("kernel/watchdog: Prevent false positives with turbo modes") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19tick/broadcast: Make takeover of broadcast hrtimer reliableYu Liao
commit f7d43dd206e7e18c182f200e67a8db8c209907fa upstream. Running the LTP hotplug stress test on a aarch64 machine results in rcu_sched stall warnings when the broadcast hrtimer was owned by the un-plugged CPU. The issue is the following: CPU1 (owns the broadcast hrtimer) CPU2 tick_broadcast_enter() // shutdown local timer device broadcast_shutdown_local() ... tick_broadcast_exit() clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT) // timer device is not programmed cpumask_set_cpu(cpu, tick_broadcast_force_mask) initiates offlining of CPU1 take_cpu_down() /* * CPU1 shuts down and does not * send broadcast IPI anymore */ takedown_cpu() hotplug_cpu__broadcast_tick_pull() // move broadcast hrtimer to this CPU clockevents_program_event() bc_set_next() hrtimer_start() /* * timer device is not programmed * because only the first expiring * timer will trigger clockevent * device reprogramming */ What happens is that CPU2 exits broadcast mode with force bit set, then the local timer device is not reprogrammed and CPU2 expects to receive the expired event by the broadcast IPI. But this does not happen because CPU1 is offlined by CPU2. CPU switches the clockevent device to ONESHOT state, but does not reprogram the device. The subsequent reprogramming of the hrtimer broadcast device does not program the clockevent device of CPU2 either because the pending expiry time is already in the past and the CPU expects the event to be delivered. As a consequence all CPUs which wait for a broadcast event to be delivered are stuck forever. Fix this issue by reprogramming the local timer device if the broadcast force bit of the CPU is set so that the broadcast hrtimer is delivered. [ tglx: Massage comment and change log. Add Fixes tag ] Fixes: 989dcb645ca7 ("tick: Handle broadcast wakeup of multiple cpus") Signed-off-by: Yu Liao <liaoyu15@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240711124843.64167-1-liaoyu15@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19perf: Prevent passing zero nr_pages to rb_alloc_aux()Adrian Hunter
[ Upstream commit dbc48c8f41c208082cfa95e973560134489e3309 ] nr_pages is unsigned long but gets passed to rb_alloc_aux() as an int, and is stored as an int. Only power-of-2 values are accepted, so if nr_pages is a 64_bit value, it will be passed to rb_alloc_aux() as zero. That is not ideal because: 1. the value is incorrect 2. rb_alloc_aux() is at risk of misbehaving, although it manages to return -ENOMEM in that case, it is a result of passing zero to get_order() even though the get_order() result is documented to be undefined in that case. Fix by simply validating the maximum supported value in the first place. Use -ENOMEM error code for consistency with the current error code that is returned in that case. Fixes: 45bfb2e50471 ("perf: Add AUX area to ring buffer for raw data streams") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240624201101.60186-6-adrian.hunter@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-19perf: Fix perf_aux_size() for greater-than 32-bit sizeAdrian Hunter
[ Upstream commit 3df94a5b1078dfe2b0c03f027d018800faf44c82 ] perf_buffer->aux_nr_pages uses a 32-bit type, so a cast is needed to calculate a 64-bit size. Fixes: 45bfb2e50471 ("perf: Add AUX area to ring buffer for raw data streams") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240624201101.60186-5-adrian.hunter@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18mm: optimize the redundant loop of mm_update_owner_next()Jinliang Zheng
commit cf3f9a593dab87a032d2b6a6fb205e7f3de4f0a1 upstream. When mm_update_owner_next() is racing with swapoff (try_to_unuse()) or /proc or ptrace or page migration (get_task_mm()), it is impossible to find an appropriate task_struct in the loop whose mm_struct is the same as the target mm_struct. If the above race condition is combined with the stress-ng-zombie and stress-ng-dup tests, such a long loop can easily cause a Hard Lockup in write_lock_irq() for tasklist_lock. Recognize this situation in advance and exit early. Link: https://lkml.kernel.org/r/20240620122123.3877432-1-alexjlzheng@tencent.com Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tycho Andersen <tandersen@netflix.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05perf/core: Fix missing wakeup when waiting for context referenceHaifeng Xu
[ Upstream commit 74751ef5c1912ebd3e65c3b65f45587e05ce5d36 ] In our production environment, we found many hung tasks which are blocked for more than 18 hours. Their call traces are like this: [346278.191038] __schedule+0x2d8/0x890 [346278.191046] schedule+0x4e/0xb0 [346278.191049] perf_event_free_task+0x220/0x270 [346278.191056] ? init_wait_var_entry+0x50/0x50 [346278.191060] copy_process+0x663/0x18d0 [346278.191068] kernel_clone+0x9d/0x3d0 [346278.191072] __do_sys_clone+0x5d/0x80 [346278.191076] __x64_sys_clone+0x25/0x30 [346278.191079] do_syscall_64+0x5c/0xc0 [346278.191083] ? syscall_exit_to_user_mode+0x27/0x50 [346278.191086] ? do_syscall_64+0x69/0xc0 [346278.191088] ? irqentry_exit_to_user_mode+0x9/0x20 [346278.191092] ? irqentry_exit+0x19/0x30 [346278.191095] ? exc_page_fault+0x89/0x160 [346278.191097] ? asm_exc_page_fault+0x8/0x30 [346278.191102] entry_SYSCALL_64_after_hwframe+0x44/0xae The task was waiting for the refcount become to 1, but from the vmcore, we found the refcount has already been 1. It seems that the task didn't get woken up by perf_event_release_kernel() and got stuck forever. The below scenario may cause the problem. Thread A Thread B ... ... perf_event_free_task perf_event_release_kernel ... acquire event->child_mutex ... get_ctx ... release event->child_mutex acquire ctx->mutex ... perf_free_event (acquire/release event->child_mutex) ... release ctx->mutex wait_var_event acquire ctx->mutex acquire event->child_mutex # move existing events to free_list release event->child_mutex release ctx->mutex put_ctx ... ... In this case, all events of the ctx have been freed, so we couldn't find the ctx in free_list and Thread A will miss the wakeup. It's thus necessary to add a wakeup after dropping the reference. Fixes: 1cf8dfe8a661 ("perf/core: Fix race between close() and fork()") Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20240513103948.33570-1-haifeng.xu@shopee.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05kheaders: explicitly define file modes for archived headersMatthias Maennich
[ Upstream commit 3bd27a847a3a4827a948387cc8f0dbc9fa5931d5 ] Build environments might be running with different umask settings resulting in indeterministic file modes for the files contained in kheaders.tar.xz. The file itself is served with 444, i.e. world readable. Archive the files explicitly with 744,a+X to improve reproducibility across build environments. --mode=0444 is not suitable as directories need to be executable. Also, 444 makes it hard to delete all the readonly files after extraction. Cc: stable@vger.kernel.org Signed-off-by: Matthias Maennich <maennich@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05Revert "kheaders: substituting --sort in archive creation"Masahiro Yamada
[ Upstream commit 49c386ebbb43394ff4773ce24f726f6afc4c30c8 ] This reverts commit 700dea5a0bea9f64eba89fae7cb2540326fdfdc1. The reason for that commit was --sort=ORDER introduced in tar 1.28 (2014). More than 3 years have passed since then. Requiring GNU tar 1.28 should be fine now because we require GCC 5.1 (2015). Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Stable-dep-of: 3bd27a847a3a ("kheaders: explicitly define file modes for archived headers") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05tracing: Add MODULE_DESCRIPTION() to preemptirq_delay_testJeff Johnson
[ Upstream commit 23748e3e0fbfe471eff5ce439921629f6a427828 ] Fix the 'make W=1' warning: WARNING: modpost: missing MODULE_DESCRIPTION() in kernel/trace/preemptirq_delay_test.o Link: https://lore.kernel.org/linux-trace-kernel/20240518-md-preemptirq_delay_test-v1-1-387d11b30d85@quicinc.com Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Fixes: f96e8577da10 ("lib: Add module for testing preemptoff/irqsoff latency tracers") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05gcov: add support for GCC 14Peter Oberparleiter
commit c1558bc57b8e5b4da5d821537cd30e2e660861d8 upstream. Using gcov on kernels compiled with GCC 14 results in truncated 16-byte long .gcda files with no usable data. To fix this, update GCOV_COUNTERS to match the value defined by GCC 14. Tested with GCC versions 14.1.0 and 13.2.0. Link: https://lkml.kernel.org/r/20240610092743.1609845-1-oberpar@linux.ibm.com Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Reported-by: Allison Henderson <allison.henderson@oracle.com> Reported-by: Chuck Lever III <chuck.lever@oracle.com> Tested-by: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>