diff options
| author | Peter Hutterer <peter.hutterer@who-t.net> | 2013-02-14 16:31:13 +1000 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2013-02-14 11:01:21 -0800 |
| commit | 9a35d4240e2aa91ac104f0f9f86f83ff9a2d3d04 (patch) | |
| tree | 5bb541b3108b9718cc1eee52d50aa0a0c012ea23 | |
| parent | 955d434f4d755d00a24ae4068b9957765989d672 (diff) | |
os: fix pnprintf OOB buffer read for unterminated length modifiers
Format strings with length modifiers but missing format specifier like "%0"
will read one byte past the array size.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
| -rw-r--r-- | os/log.c | 3 | ||||
| -rw-r--r-- | test/signal-logging.c | 8 |
2 files changed, 11 insertions, 0 deletions
@@ -304,6 +304,9 @@ pnprintf(char *string, size_t size, const char *f, va_list args) while (f_idx < f_len && ((f[f_idx] >= '0' && f[f_idx] <= '9') || f[f_idx] == '.')) f_idx++; + if (f_idx >= f_len) + break; + switch (f[f_idx]) { case 's': string_arg = va_arg(args, char*); diff --git a/test/signal-logging.c b/test/signal-logging.c index 1ef17af2c..e0eb81006 100644 --- a/test/signal-logging.c +++ b/test/signal-logging.c @@ -199,6 +199,14 @@ static void logging_format(void) read_log_msg(logmsg); assert(strcmp(logmsg, "(EE) substituted string\n") == 0); + /* Invalid format */ +#warning Ignore compiler warning below "lacks type at end of format". This is intentional. + LogMessageVerbSigSafe(X_ERROR, -1, "%4", 4); + read_log_msg(logmsg); + assert(strcmp(logmsg, "(EE) ") == 0); + LogMessageVerbSigSafe(X_ERROR, -1, "\n"); + fseek(f, 0, SEEK_END); + /* number substitution */ ui = 0; do { |