From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- include/asm-generic/sections.h | 235 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 235 insertions(+) create mode 100644 include/asm-generic/sections.h (limited to 'include/asm-generic/sections.h') diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h new file mode 100644 index 000000000..0755bc39b --- /dev/null +++ b/include/asm-generic/sections.h @@ -0,0 +1,235 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_SECTIONS_H_ +#define _ASM_GENERIC_SECTIONS_H_ + +/* References to section boundaries */ + +#include +#include + +/* + * Usage guidelines: + * _text, _data: architecture specific, don't use them in arch-independent code + * [_stext, _etext]: contains .text.* sections, may also contain .rodata.* + * and/or .init.* sections + * [_sdata, _edata]: contains .data.* sections, may also contain .rodata.* + * and/or .init.* sections. + * [__start_rodata, __end_rodata]: contains .rodata.* sections + * [__start_ro_after_init, __end_ro_after_init]: + * contains .data..ro_after_init section + * [__init_begin, __init_end]: contains .init.* sections, but .init.text.* + * may be out of this range on some architectures. + * [_sinittext, _einittext]: contains .init.text.* sections + * [__bss_start, __bss_stop]: contains BSS sections + * + * Following global variables are optional and may be unavailable on some + * architectures and/or kernel configurations. + * _text, _data + * __kprobes_text_start, __kprobes_text_end + * __entry_text_start, __entry_text_end + * __ctors_start, __ctors_end + * __irqentry_text_start, __irqentry_text_end + * __softirqentry_text_start, __softirqentry_text_end + * __start_opd, __end_opd + */ +extern char _text[], _stext[], _etext[]; +extern char _data[], _sdata[], _edata[]; +extern char __bss_start[], __bss_stop[]; +extern char __init_begin[], __init_end[]; +extern char _sinittext[], _einittext[]; +extern char __start_ro_after_init[], __end_ro_after_init[]; +extern char _end[]; +extern char __per_cpu_start[], __per_cpu_end[]; +extern char __kprobes_text_start[], __kprobes_text_end[]; +extern char __entry_text_start[], __entry_text_end[]; +extern char __start_rodata[], __end_rodata[]; +extern char __irqentry_text_start[], __irqentry_text_end[]; +extern char __softirqentry_text_start[], __softirqentry_text_end[]; +extern char __start_once[], __end_once[]; + +/* Start and end of .ctors section - used for constructor calls. */ +extern char __ctors_start[], __ctors_end[]; + +/* Start and end of .opd section - used for function descriptors. */ +extern char __start_opd[], __end_opd[]; + +/* Start and end of instrumentation protected text section */ +extern char __noinstr_text_start[], __noinstr_text_end[]; + +extern __visible const void __nosave_begin, __nosave_end; + +/* Function descriptor handling (if any). Override in asm/sections.h */ +#ifdef CONFIG_HAVE_FUNCTION_DESCRIPTORS +void *dereference_function_descriptor(void *ptr); +void *dereference_kernel_function_descriptor(void *ptr); +#else +#define dereference_function_descriptor(p) ((void *)(p)) +#define dereference_kernel_function_descriptor(p) ((void *)(p)) + +/* An address is simply the address of the function. */ +typedef struct { + unsigned long addr; +} func_desc_t; +#endif + +static inline bool have_function_descriptors(void) +{ + return IS_ENABLED(CONFIG_HAVE_FUNCTION_DESCRIPTORS); +} + +/** + * memory_contains - checks if an object is contained within a memory region + * @begin: virtual address of the beginning of the memory region + * @end: virtual address of the end of the memory region + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if the object specified by @virt and @size is entirely + * contained within the memory region defined by @begin and @end, false + * otherwise. + */ +static inline bool memory_contains(void *begin, void *end, void *virt, + size_t size) +{ + return virt >= begin && virt + size <= end; +} + +/** + * memory_intersects - checks if the region occupied by an object intersects + * with another memory region + * @begin: virtual address of the beginning of the memory region + * @end: virtual address of the end of the memory region + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if an object's memory region, specified by @virt and @size, + * intersects with the region specified by @begin and @end, false otherwise. + */ +static inline bool memory_intersects(void *begin, void *end, void *virt, + size_t size) +{ + void *vend = virt + size; + + if (virt < end && vend > begin) + return true; + + return false; +} + +/** + * init_section_contains - checks if an object is contained within the init + * section + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if the object specified by @virt and @size is entirely + * contained within the init section, false otherwise. + */ +static inline bool init_section_contains(void *virt, size_t size) +{ + return memory_contains(__init_begin, __init_end, virt, size); +} + +/** + * init_section_intersects - checks if the region occupied by an object + * intersects with the init section + * @virt: virtual address of the memory object + * @size: size of the memory object + * + * Returns: true if an object's memory region, specified by @virt and @size, + * intersects with the init section, false otherwise. + */ +static inline bool init_section_intersects(void *virt, size_t size) +{ + return memory_intersects(__init_begin, __init_end, virt, size); +} + +/** + * is_kernel_core_data - checks if the pointer address is located in the + * .data or .bss section + * + * @addr: address to check + * + * Returns: true if the address is located in .data or .bss, false otherwise. + * Note: On some archs it may return true for core RODATA, and false + * for others. But will always be true for core RW data. + */ +static inline bool is_kernel_core_data(unsigned long addr) +{ + if (addr >= (unsigned long)_sdata && addr < (unsigned long)_edata) + return true; + + if (addr >= (unsigned long)__bss_start && + addr < (unsigned long)__bss_stop) + return true; + + return false; +} + +/** + * is_kernel_rodata - checks if the pointer address is located in the + * .rodata section + * + * @addr: address to check + * + * Returns: true if the address is located in .rodata, false otherwise. + */ +static inline bool is_kernel_rodata(unsigned long addr) +{ + return addr >= (unsigned long)__start_rodata && + addr < (unsigned long)__end_rodata; +} + +static inline bool is_kernel_ro_after_init(unsigned long addr) +{ + return addr >= (unsigned long)__start_ro_after_init && + addr < (unsigned long)__end_ro_after_init; +} +/** + * is_kernel_inittext - checks if the pointer address is located in the + * .init.text section + * + * @addr: address to check + * + * Returns: true if the address is located in .init.text, false otherwise. + */ +static inline bool is_kernel_inittext(unsigned long addr) +{ + return addr >= (unsigned long)_sinittext && + addr < (unsigned long)_einittext; +} + +/** + * __is_kernel_text - checks if the pointer address is located in the + * .text section + * + * @addr: address to check + * + * Returns: true if the address is located in .text, false otherwise. + * Note: an internal helper, only check the range of _stext to _etext. + */ +static inline bool __is_kernel_text(unsigned long addr) +{ + return addr >= (unsigned long)_stext && + addr < (unsigned long)_etext; +} + +/** + * __is_kernel - checks if the pointer address is located in the kernel range + * + * @addr: address to check + * + * Returns: true if the address is located in the kernel range, false otherwise. + * Note: an internal helper, check the range of _stext to _end, + * and range from __init_begin to __init_end, which can be outside + * of the _stext to _end range. + */ +static inline bool __is_kernel(unsigned long addr) +{ + return ((addr >= (unsigned long)_stext && + addr < (unsigned long)_end) || + (addr >= (unsigned long)__init_begin && + addr < (unsigned long)__init_end)); +} + +#endif /* _ASM_GENERIC_SECTIONS_H_ */ -- cgit v1.3.1