4ed8f337de
This reverts commit2e9906f84f. It was turned out that commit2e9906f84f("tracing: Add "(fault)" name injection to kernel probes") did not work correctly and probe events still show just '(fault)' (instead of '"(fault)"'). Also, current '(fault)' is more explicit that it faulted. This also moves FAULT_STRING macro to trace.h so that synthetic event can keep using it, and uses it in trace_probe.c too. Link: https://lore.kernel.org/all/168908495772.123124.1250788051922100079.stgit@devnote2/ Link: https://lore.kernel.org/all/20230706230642.3793a593@rorschach.local.home/ Cc: stable@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
115 lines
2.8 KiB
C
115 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __TRACE_PROBE_KERNEL_H_
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#define __TRACE_PROBE_KERNEL_H_
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/*
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* This depends on trace_probe.h, but can not include it due to
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* the way trace_probe_tmpl.h is used by trace_kprobe.c and trace_eprobe.c.
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* Which means that any other user must include trace_probe.h before including
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* this file.
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*/
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/* Return the length of string -- including null terminal byte */
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static nokprobe_inline int
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fetch_store_strlen_user(unsigned long addr)
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{
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const void __user *uaddr = (__force const void __user *)addr;
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return strnlen_user_nofault(uaddr, MAX_STRING_SIZE);
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}
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/* Return the length of string -- including null terminal byte */
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static nokprobe_inline int
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fetch_store_strlen(unsigned long addr)
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{
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int ret, len = 0;
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u8 c;
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#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
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if (addr < TASK_SIZE)
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return fetch_store_strlen_user(addr);
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#endif
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do {
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ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1);
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len++;
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} while (c && ret == 0 && len < MAX_STRING_SIZE);
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return (ret < 0) ? ret : len;
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}
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/*
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* Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
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* with max length and relative data location.
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*/
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static nokprobe_inline int
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fetch_store_string_user(unsigned long addr, void *dest, void *base)
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{
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const void __user *uaddr = (__force const void __user *)addr;
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int maxlen = get_loc_len(*(u32 *)dest);
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void *__dest;
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long ret;
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if (unlikely(!maxlen))
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return -ENOMEM;
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__dest = get_loc_data(dest, base);
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ret = strncpy_from_user_nofault(__dest, uaddr, maxlen);
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if (ret >= 0)
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*(u32 *)dest = make_data_loc(ret, __dest - base);
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return ret;
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}
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/*
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* Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
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* length and relative data location.
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*/
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static nokprobe_inline int
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fetch_store_string(unsigned long addr, void *dest, void *base)
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{
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int maxlen = get_loc_len(*(u32 *)dest);
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void *__dest;
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long ret;
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#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
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if ((unsigned long)addr < TASK_SIZE)
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return fetch_store_string_user(addr, dest, base);
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#endif
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if (unlikely(!maxlen))
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return -ENOMEM;
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__dest = get_loc_data(dest, base);
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/*
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* Try to get string again, since the string can be changed while
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* probing.
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*/
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ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen);
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if (ret >= 0)
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*(u32 *)dest = make_data_loc(ret, __dest - base);
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return ret;
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}
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static nokprobe_inline int
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probe_mem_read_user(void *dest, void *src, size_t size)
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{
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const void __user *uaddr = (__force const void __user *)src;
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return copy_from_user_nofault(dest, uaddr, size);
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}
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static nokprobe_inline int
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probe_mem_read(void *dest, void *src, size_t size)
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{
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#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
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if ((unsigned long)src < TASK_SIZE)
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return probe_mem_read_user(dest, src, size);
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#endif
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return copy_from_kernel_nofault(dest, src, size);
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}
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#endif /* __TRACE_PROBE_KERNEL_H_ */
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