From 963ddb917de3140308ee62fb642b2307a577a39e Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 24 Sep 2012 23:22:19 +0200 Subject: [PATCH] log: fix repeated invocation of vsnprintf()/vaprintf() in log_struct() https://bugs.freedesktop.org/show_bug.cgi?id=55213 --- src/nspawn/nspawn.c | 6 ++++++ src/shared/log.c | 22 ++++++++++++++++++++-- src/shared/macro.h | 43 +++++++++++++++++++++++++++++++++++++++++++ src/test/test-log.c | 7 +++++++ 4 files changed, 76 insertions(+), 2 deletions(-) diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 959df4e..5cac32c 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -1307,6 +1307,12 @@ int main(int argc, char *argv[]) { if (arg_user) { + /* Note that this resolves user names + * inside the container, and hence + * accesses the NSS modules from the + * container and not the host. This is + * a bit weird... */ + if (get_user_creds((const char**)&arg_user, &uid, &gid, &home, NULL) < 0) { log_error("get_user_creds() failed: %m"); goto child_fail; diff --git a/src/shared/log.c b/src/shared/log.c index b618458..6357868 100644 --- a/src/shared/log.c +++ b/src/shared/log.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "log.h" #include "util.h" @@ -705,11 +706,23 @@ int log_struct_internal( va_start(ap, format); while (format && n + 1 < ELEMENTSOF(iovec)) { char *buf; + va_list aq; - if (vasprintf(&buf, format, ap) < 0) { + /* We need to copy the va_list structure, + * since vasprintf() leaves it afterwards at + * an undefined location */ + + va_copy(aq, ap); + if (vasprintf(&buf, format, aq) < 0) { + va_end(aq); r = -ENOMEM; goto finish; } + va_end(aq); + + /* Now, jump enough ahead, so that we point to + * the next format string */ + VA_FORMAT_ADVANCE(format, ap); IOVEC_SET_STRING(iovec[n++], buf); @@ -742,8 +755,11 @@ int log_struct_internal( va_start(ap, format); while (format) { + va_list aq; - vsnprintf(buf, sizeof(buf), format, ap); + va_copy(aq, ap); + vsnprintf(buf, sizeof(buf), format, aq); + va_end(aq); char_array_0(buf); if (startswith(buf, "MESSAGE=")) { @@ -751,6 +767,8 @@ int log_struct_internal( break; } + VA_FORMAT_ADVANCE(format, ap); + format = va_arg(ap, char *); } va_end(ap); diff --git a/src/shared/macro.h b/src/shared/macro.h index c7ce7c8..0dd210a 100644 --- a/src/shared/macro.h +++ b/src/shared/macro.h @@ -193,4 +193,47 @@ static inline size_t IOVEC_INCREMENT(struct iovec *i, unsigned n, size_t k) { #define _cleanup_closedir_ __attribute__((cleanup(closedirp))) #define _cleanup_umask_ __attribute__((cleanup(umaskp))) +#define VA_FORMAT_ADVANCE(format, ap) do { \ + int _argtypes[64]; \ + size_t _i, _k; \ + _k = parse_printf_format((format), ELEMENTSOF(_argtypes), _argtypes); \ + for (_i = 0; _i < _k; _i++) { \ + if (_argtypes[_i] & PA_FLAG_PTR) { \ + (void) va_arg(ap, void*); \ + continue; \ + } \ + \ + switch (_argtypes[_i]) { \ + case PA_INT: \ + case PA_INT|PA_FLAG_SHORT: \ + case PA_CHAR: \ + (void) va_arg(ap, int); \ + break; \ + case PA_INT|PA_FLAG_LONG: \ + (void) va_arg(ap, long int); \ + break; \ + case PA_INT|PA_FLAG_LONG_LONG: \ + (void) va_arg(ap, long long int); \ + break; \ + case PA_WCHAR: \ + (void) va_arg(ap, wchar_t); \ + break; \ + case PA_WSTRING: \ + case PA_STRING: \ + case PA_POINTER: \ + (void) va_arg(ap, void*); \ + break; \ + case PA_FLOAT: \ + case PA_DOUBLE: \ + (void) va_arg(ap, double); \ + break; \ + case PA_DOUBLE|PA_FLAG_LONG_DOUBLE: \ + (void) va_arg(ap, long double); \ + break; \ + default: \ + assert_not_reached("Unknown format string argument."); \ + } \ + } \ +} while(false) + #include "log.h" diff --git a/src/test/test-log.c b/src/test/test-log.c index cc924fa..8dc3d53 100644 --- a/src/test/test-log.c +++ b/src/test/test-log.c @@ -42,5 +42,12 @@ int main(int argc, char* argv[]) { "SERVICE=foobar", NULL); + log_struct(LOG_INFO, + "MESSAGE=Foobar PID=%lu", (unsigned long) getpid(), + "FORMAT_STR_TEST=1=%i A=%c 2=%hi 3=%li 4=%lli 1=%p foo=%s 2.5=%g 3.5=%g 4.5=%Lg", + (int) 1, 'A', (short) 2, (long int) 3, (long long int) 4, (void*) 1, "foo", (float) 2.5f, (double) 3.5, (long double) 4.5, + "SUFFIX=GOT IT", + NULL); + return 0; } -- 2.7.4