Merge branch 'bug33087_041' into bug33087_042

This commit is contained in:
teor 2020-02-12 19:19:43 +10:00
commit b6d1f99cb2
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7 changed files with 11 additions and 71 deletions

4
changes/bug33087 Normal file
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@ -0,0 +1,4 @@
o Minor bugfixes (logging):
- Stop closing stderr and stdout during shutdown. Closing these file
descriptors can hide sanitiser logs.
Fixes bug 33087; bugfix on 0.4.1.6.

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@ -150,32 +150,6 @@ tor_log_reset_sigsafe_err_fds(void)
tor_log_set_sigsafe_err_fds(fds, 1);
}
/**
* Close the list of fds that get errors from inside a signal handler or
* other emergency condition. These fds are shared with the logging code:
* closing them flushes the log buffers, and prevents any further logging.
*
* This function closes stderr, so it should only be called immediately before
* process shutdown.
*/
void
tor_log_close_sigsafe_err_fds(void)
{
int n_fds, i;
const int *fds = NULL;
n_fds = tor_log_get_sigsafe_err_fds(&fds);
for (i = 0; i < n_fds; ++i) {
/* tor_log_close_sigsafe_err_fds_on_error() is called on error and on
* shutdown, so we can't log or take any useful action if close()
* fails. */
(void)close(fds[i]);
}
/* Don't even try logging, we've closed all the log fds. */
tor_log_set_sigsafe_err_fds(NULL, 0);
}
/**
* Set the granularity (in ms) to use when reporting fatal errors outside
* the logging system.
@ -217,13 +191,12 @@ tor_raw_assertion_failed_msg_(const char *file, int line, const char *expr,
/**
* Call the abort() function to kill the current process with a fatal
* error. But first, close the raw error file descriptors, so error messages
* are written before process termination.
* error. This is a separate function, so that log users don't have to include
* the header for abort().
**/
void
tor_raw_abort_(void)
{
tor_log_close_sigsafe_err_fds();
abort();
}

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@ -40,7 +40,6 @@ void tor_log_err_sigsafe(const char *m, ...);
int tor_log_get_sigsafe_err_fds(const int **out);
void tor_log_set_sigsafe_err_fds(const int *fds, int n);
void tor_log_reset_sigsafe_err_fds(void);
void tor_log_close_sigsafe_err_fds(void);
void tor_log_sigsafe_err_set_granularity(int ms);
void tor_raw_abort_(void) ATTR_NORETURN;

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@ -27,11 +27,8 @@ subsys_torerr_initialize(void)
static void
subsys_torerr_shutdown(void)
{
/* Stop handling signals with backtraces, then close the logs. */
/* Stop handling signals with backtraces. */
clean_up_backtrace_handler();
/* We can't log any log messages after this point: we've closed all the log
* fds, including stdio. */
tor_log_close_sigsafe_err_fds();
}
const subsys_fns_t sys_torerr = {

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@ -667,12 +667,8 @@ tor_log_update_sigsafe_err_fds(void)
/* log_fds and err_fds contain matching entries: log_fds are the fds used by
* the log module, and err_fds are the fds used by the err module.
* For stdio logs, the log_fd and err_fd values are identical,
* and the err module closes the fd on shutdown.
* For file logs, the err_fd is a dup() of the log_fd,
* and the log and err modules both close their respective fds on shutdown.
* (Once all fds representing a file are closed, the underlying file is
* closed.)
* For stdio logs, the log_fd and err_fd values are identical.
* For file logs, the err_fd is a dup() of the log_fd.
*/
int log_fds[TOR_SIGSAFE_LOG_MAX_FDS];
int err_fds[TOR_SIGSAFE_LOG_MAX_FDS];
@ -704,12 +700,10 @@ tor_log_update_sigsafe_err_fds(void)
log_fds[n_fds] = lf->fd;
if (lf->needs_close) {
/* File log fds are duplicated, because close_log() closes the log
* module's fd, and tor_log_close_sigsafe_err_fds() closes the err
* module's fd. Both refer to the same file. */
err_fds[n_fds] = dup(lf->fd);
} else {
/* stdio log fds are not closed by the log module.
* tor_log_close_sigsafe_err_fds() closes stdio logs. */
/* stdio log fds are not closed by the log module. */
err_fds[n_fds] = lf->fd;
}
n_fds++;
@ -841,30 +835,6 @@ logs_free_all(void)
* log mutex. */
}
/** Close signal-safe log files.
* Closing the log files makes the process and OS flush log buffers.
*
* This function is safe to call from a signal handler. It should only be
* called when shutting down the log or err modules. It is currenly called
* by the err module, when terminating the process on an abnormal condition.
*/
void
logs_close_sigsafe(void)
{
logfile_t *victim, *next;
/* We can't LOCK_LOGS() in a signal handler, because it may call
* signal-unsafe functions. And we can't deallocate memory, either. */
next = logfiles;
logfiles = NULL;
while (next) {
victim = next;
next = next->next;
if (victim->needs_close) {
close_log_sigsafe(victim);
}
}
}
/** Remove and free the log entry <b>victim</b> from the linked-list
* logfiles (it is probably present, but it might not be due to thread
* racing issues). After this function is called, the caller shouldn't

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@ -184,7 +184,6 @@ void logs_set_domain_logging(int enabled);
int get_min_log_level(void);
void switch_logs_debug(void);
void logs_free_all(void);
void logs_close_sigsafe(void);
void add_temp_log(int min_severity);
void close_temp_logs(void);
void rollback_log_changes(void);

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@ -163,8 +163,7 @@ tor_bug_occurred_(const char *fname, unsigned int line,
/**
* Call the tor_raw_abort_() function to close raw logs, then kill the current
* process with a fatal error. But first, close the file-based log file
* descriptors, so error messages are written before process termination.
* process with a fatal error.
*
* (This is a separate function so that we declare it in util_bug.h without
* including torerr.h in all the users of util_bug.h)
@ -172,7 +171,6 @@ tor_bug_occurred_(const char *fname, unsigned int line,
void
tor_abort_(void)
{
logs_close_sigsafe();
tor_raw_abort_();
}