/* * Access kernel memory without faulting. */ #include #include #include /** * probe_kernel_read(): safely attempt to read from a location * @dst: pointer to the buffer that shall take the data * @src: address to read from * @size: size of the data chunk * * Safely read from address @src to the buffer at @dst. If a kernel fault * happens, handle that and return -EFAULT. * * We ensure that the copy_from_user is executed in atomic context so that * do_page_fault() doesn't attempt to take mmap_sem. This makes * probe_kernel_read() suitable for use within regions where the caller * already holds mmap_sem, or other locks which nest inside mmap_sem. */ long __weak probe_kernel_read(void *dst, const void *src, size_t size) __attribute__((alias("__probe_kernel_read"))); long __probe_kernel_read(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); pagefault_disable(); ret = __copy_from_user_inatomic(dst, (__force const void __user *)src, size); pagefault_enable(); set_fs(old_fs); return ret ? -EFAULT : 0; } EXPORT_SYMBOL_GPL(probe_kernel_read); /** * probe_kernel_write(): safely attempt to write to a location * @dst: address to write to * @src: pointer to the data that shall be written * @size: size of the data chunk * * Safely write to address @dst from the buffer at @src. If a kernel fault * happens, handle that and return -EFAULT. */ long __weak probe_kernel_write(void *dst, const void *src, size_t size) __attribute__((alias("__probe_kernel_write"))); long __probe_kernel_write(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); pagefault_disable(); ret = __copy_to_user_inatomic((__force void __user *)dst, src, size); pagefault_enable(); set_fs(old_fs); return ret ? -EFAULT : 0; } EXPORT_SYMBOL_GPL(probe_kernel_write); /** * strncpy_from_unsafe: - Copy a NUL terminated string from unsafe address. * @dst: Destination address, in kernel space. This buffer must be at * least @count bytes long. * @src: Unsafe address. * @count: Maximum number of bytes to copy, including the trailing NUL. * * Copies a NUL-terminated string from unsafe address to kernel buffer. * * On success, returns the length of the string INCLUDING the trailing NUL. * * If access fails, returns -EFAULT (some data may have been copied * and the trailing NUL added). * * If @count is smaller than the length of the string, copies @count-1 bytes, * sets the last byte of @dst buffer to NUL and returns @count. */ long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count) { mm_segment_t old_fs = get_fs(); const void *src = unsafe_addr; long ret; if (unlikely(count <= 0)) return 0; set_fs(KERNEL_DS); pagefault_disable(); do { ret = __get_user(*dst++, (const char __user __force *)src++); } while (dst[-1] && ret == 0 && src - unsafe_addr < count); dst[-1] = '\0'; pagefault_enable(); set_fs(old_fs); return ret ? -EFAULT : src - unsafe_addr; } te-remove&id=24d615a694d649aa2e167c3f97f62bdad07e3f84'>net/bluetooth/selftest.h
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authorAleksander Morgado <aleksander@aleksander.es>2017-01-18 21:31:31 +0100
committerJohan Hovold <johan@kernel.org>2017-01-19 09:08:37 +0100
commit24d615a694d649aa2e167c3f97f62bdad07e3f84 (patch)
tree2fe33c115bdec6bf4b01e27afd90bb16fa668e22 /net/bluetooth/selftest.h
parent49def1853334396f948dcb4cedb9347abb318df5 (diff)
USB: serial: qcserial: add Dell DW5570 QDL
The Dell DW5570 is a re-branded Sierra Wireless MC8805 which will by default boot with vid 0x413c and pid 0x81a3. When triggered QDL download mode, the device switches to pid 0x81a6 and provides the standard TTY used for firmware upgrade. Cc: <stable@vger.kernel.org> Signed-off-by: Aleksander Morgado <aleksander@aleksander.es> Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'net/bluetooth/selftest.h')