diff options
| -rw-r--r-- | kernel/printk/printk.c | 40 |
1 files changed, 36 insertions, 4 deletions
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 272ca69e3752..fe3cd92a5a4e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -786,7 +786,34 @@ void log_buf_release(struct kref *ref) kfree(log_b); } -static int kmsg_sys_write(int minor, int level, const char *fmt, ...) +#define MAX_PID_LEN 20 +#define MAX_TID_LEN 20 +/* + * Fromat below describes dict appended to message written from userspace: + * "_PID=<pid>\0_TID=<tid>\0_COMM=<comm>" + * KMSG_DICT_MAX_LEN definition represents maximal length of this dict. + */ +#define KMSG_DICT_MAX_LEN (5 + MAX_PID_LEN + 1 + \ + 5 + MAX_TID_LEN + 1 + \ + 6 + TASK_COMM_LEN) + +static size_t set_kmsg_dict(char *buf) +{ + size_t len; + + len = sprintf(buf, "_PID=%d", task_tgid_nr(current)) + 1; + len += sprintf(buf + len, "_TID=%d", task_pid_nr(current)) + 1; + memcpy(buf + len, "_COMM=", 6); + len += 6; + get_task_comm(buf + len, current); + while (buf[len] != '\0') + len++; + return len; +} + +static int kmsg_sys_write(int minor, int level, + const char *dict, size_t dictlen, + const char *fmt, ...) { va_list args; int ret = -ENXIO; @@ -801,7 +828,7 @@ static int kmsg_sys_write(int minor, int level, const char *fmt, ...) va_start(args, fmt); log_format_and_store(log_b, 1 /* LOG_USER */, level, - NULL, 0, fmt, args); + dict, dictlen, fmt, args); va_end(args); wake_up_interruptible(&log_b->wait); @@ -821,6 +848,8 @@ static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from) int level = default_message_loglevel; int facility = 1; /* LOG_USER */ size_t len = iov_iter_count(from); + char dict[KMSG_DICT_MAX_LEN]; + size_t dictlen; ssize_t ret = len; int minor = iminor(iocb->ki_filp->f_inode); @@ -860,10 +889,13 @@ static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from) } } + dictlen = set_kmsg_dict(dict); + if (minor == log_buf.minor) { - printk_emit(facility, level, NULL, 0, "%s", line); + printk_emit(facility, level, dict, dictlen, "%s", line); } else { - int error = kmsg_sys_write(minor, level, "%s", line); + int error = kmsg_sys_write(minor, level, dict, dictlen, + "%s", line); if (error) ret = error; |