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Diffstat (limited to 'xorg-server/os')
-rw-r--r--xorg-server/os/backtrace.c49
-rw-r--r--xorg-server/os/log.c175
-rw-r--r--xorg-server/os/osinit.c8
-rw-r--r--xorg-server/os/utils.c46
4 files changed, 250 insertions, 28 deletions
diff --git a/xorg-server/os/backtrace.c b/xorg-server/os/backtrace.c
index 81348f417..daac60cf6 100644
--- a/xorg-server/os/backtrace.c
+++ b/xorg-server/os/backtrace.c
@@ -45,29 +45,37 @@ xorg_backtrace(void)
int size, i;
Dl_info info;
- ErrorF("\n");
- ErrorF("Backtrace:\n");
+ ErrorFSigSafe("\n");
+ ErrorFSigSafe("Backtrace:\n");
size = backtrace(array, 64);
for (i = 0; i < size; i++) {
int rc = dladdr(array[i], &info);
if (rc == 0) {
- ErrorF("%d: ?? [%p]\n", i, array[i]);
+ ErrorFSigSafe("%u: ?? [%p]\n", i, array[i]);
continue;
}
mod = (info.dli_fname && *info.dli_fname) ? info.dli_fname : "(vdso)";
if (info.dli_saddr)
- ErrorF("%d: %s (%s+0x%lx) [%p]\n", i, mod,
- info.dli_sname,
- (long unsigned int) ((char *) array[i] -
- (char *) info.dli_saddr), array[i]);
+ ErrorFSigSafe(
+ "%u: %s (%s+0x%x) [%p]\n",
+ i,
+ mod,
+ info.dli_sname,
+ (unsigned int)((char *) array[i] -
+ (char *) info.dli_saddr),
+ array[i]);
else
- ErrorF("%d: %s (%p+0x%lx) [%p]\n", i, mod,
- info.dli_fbase,
- (long unsigned int) ((char *) array[i] -
- (char *) info.dli_fbase), array[i]);
+ ErrorFSigSafe(
+ "%u: %s (%p+0x%x) [%p]\n",
+ i,
+ mod,
+ info.dli_fbase,
+ (unsigned int)((char *) array[i] -
+ (char *) info.dli_fbase),
+ array[i]);
}
- ErrorF("\n");
+ ErrorFSigSafe("\n");
}
#else /* not glibc or glibc < 2.1 */
@@ -105,7 +113,7 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
strcpy(signame, "unknown");
}
- ErrorF("** Signal %d (%s)\n", signo, signame);
+ ErrorFSigSafe("** Signal %u (%s)\n", signo, signame);
}
snprintf(header, sizeof(header), "%d: 0x%lx", depth, pc);
@@ -123,7 +131,8 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
symname = "<section start>";
offset = pc - (uintptr_t) dlinfo.dli_fbase;
}
- ErrorF("%s: %s:%s+0x%lx\n", header, dlinfo.dli_fname, symname, offset);
+ ErrorFSigSafe("%s: %s:%s+0x%x\n", header, dlinfo.dli_fname, symname,
+ offset);
}
else {
@@ -131,7 +140,7 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
* probably poke elfloader here, but haven't written that code yet,
* so we just print the pc.
*/
- ErrorF("%s\n", header);
+ ErrorFSigSafe("%s\n", header);
}
return 0;
@@ -183,7 +192,7 @@ xorg_backtrace_pstack(void)
if (bytesread > 0) {
btline[bytesread] = 0;
- ErrorF("%s", btline);
+ ErrorFSigSafe("%s", btline);
}
else if ((bytesread < 0) || ((errno != EINTR) && (errno != EAGAIN)))
done = 1;
@@ -203,8 +212,8 @@ void
xorg_backtrace(void)
{
- ErrorF("\n");
- ErrorF("Backtrace:\n");
+ ErrorFSigSafe("\n");
+ ErrorFSigSafe("Backtrace:\n");
#ifdef HAVE_PSTACK
/* First try fork/exec of pstack - otherwise fall back to walkcontext
@@ -221,9 +230,9 @@ xorg_backtrace(void)
walkcontext(&u, xorg_backtrace_frame, &depth);
else
#endif
- ErrorF("Failed to get backtrace info: %s\n", strerror(errno));
+ ErrorFSigSafe("Failed to get backtrace info: %s\n", strerror(errno));
}
- ErrorF("\n");
+ ErrorFSigSafe("\n");
}
#else
diff --git a/xorg-server/os/log.c b/xorg-server/os/log.c
index 2c13c1a7d..25da9f63a 100644
--- a/xorg-server/os/log.c
+++ b/xorg-server/os/log.c
@@ -108,6 +108,7 @@ void (*OsVendorVErrorFProc) (const char *, va_list args) = NULL;
#endif
static FILE *logFile = NULL;
+static int logFileFd = -1;
static Bool logFlush = FALSE;
static Bool logSync = FALSE;
static int logVerbosity = DEFAULT_LOG_VERBOSITY;
@@ -171,6 +172,14 @@ asm(".desc ___crashreporter_info__, 0x10");
#define X_NONE_STRING ""
#endif
+static size_t
+strlen_sigsafe(const char *s)
+{
+ size_t len;
+ for (len = 0; s[len]; len++);
+ return len;
+}
+
/*
* LogInit is called to start logging to a file. It is also called (with
* NULL arguments) when logging to a file is not wanted. It must always be
@@ -211,6 +220,8 @@ LogInit(const char *fname, const char *backup)
FatalError("Cannot open log file \"%s\"\n", logFileName);
setvbuf(logFile, NULL, _IONBF, 0);
+ logFileFd = fileno(logFile);
+
/* Flush saved log information. */
if (saveBuffer && bufferSize > 0) {
fwrite(saveBuffer, bufferPos, 1, logFile);
@@ -243,6 +254,7 @@ LogClose(enum ExitCode error)
(error == EXIT_NO_ERROR) ? "successfully" : "with error", error);
fclose(logFile);
logFile = NULL;
+ logFileFd = -1;
}
}
@@ -267,16 +279,97 @@ LogSetParameter(LogParameter param, int value)
}
}
-/* This function does the actual log message writes. */
+static int
+pnprintf(char *string, size_t size, const char *f, va_list args)
+{
+ int f_idx = 0;
+ int s_idx = 0;
+ int f_len = strlen_sigsafe(f);
+ char *string_arg;
+ char number[21];
+ int p_len;
+ int i;
+ uint64_t ui;
+
+ for (; f_idx < f_len && s_idx < size - 1; f_idx++) {
+ if (f[f_idx] != '%') {
+ string[s_idx++] = f[f_idx];
+ continue;
+ }
+
+ switch (f[++f_idx]) {
+ case 's':
+ string_arg = va_arg(args, char*);
+ p_len = strlen_sigsafe(string_arg);
+
+ for (i = 0; i < p_len && s_idx < size - 1; i++)
+ string[s_idx++] = string_arg[i];
+ break;
+
+ case 'u':
+ ui = va_arg(args, unsigned);
+ FormatUInt64(ui, number);
+ p_len = strlen_sigsafe(number);
+
+ for (i = 0; i < p_len && s_idx < size - 1; i++)
+ string[s_idx++] = number[i];
+ break;
+
+ case 'p':
+ string[s_idx++] = '0';
+ if (s_idx < size - 1)
+ string[s_idx++] = 'x';
+ ui = (uintptr_t)va_arg(args, void*);
+ FormatUInt64Hex(ui, number);
+ p_len = strlen_sigsafe(number);
+
+ for (i = 0; i < p_len && s_idx < size - 1; i++)
+ string[s_idx++] = number[i];
+ break;
+
+ case 'x':
+ ui = va_arg(args, unsigned);
+ FormatUInt64Hex(ui, number);
+ p_len = strlen_sigsafe(number);
+
+ for (i = 0; i < p_len && s_idx < size - 1; i++)
+ string[s_idx++] = number[i];
+ break;
+
+ default:
+ va_arg(args, char*);
+ string[s_idx++] = '%';
+ if (s_idx < size - 1)
+ string[s_idx++] = f[f_idx];
+ break;
+ }
+ }
+
+ string[s_idx] = '\0';
+
+ return s_idx;
+}
+
+/* This function does the actual log message writes. It must be signal safe.
+ * When attempting to call non-signal-safe functions, guard them with a check
+ * of the inSignalContext global variable. */
static void
LogSWrite(int verb, const char *buf, size_t len, Bool end_line)
{
static Bool newline = TRUE;
if (verb < 0 || logVerbosity >= verb)
- fwrite(buf, len, 1, stderr);
+ write(2, buf, len);
+
if (verb < 0 || logFileVerbosity >= verb) {
- if (logFile) {
+ if (inSignalContext && logFileFd >= 0) {
+ write(logFileFd, buf, len);
+#ifdef WIN32
+ if (logFlush && logSync)
+ fsync(logFileFd);
+#endif
+ }
+ else if (!inSignalContext && logFile) {
if (newline)
fprintf(logFile, "[%10.3f] ", GetTimeInMillis() / 1000.0);
newline = end_line;
@@ -289,7 +382,7 @@ LogSWrite(int verb, const char *buf, size_t len, Bool end_line)
#endif
}
}
- else if (needBuffer) {
+ else if (!inSignalContext && needBuffer) {
if (len > bufferUnused) {
bufferSize += 1024;
bufferUnused += 1024;
@@ -370,6 +463,16 @@ LogVMessageVerb(MessageType type, int verb, const char *format, va_list args)
Bool newline;
size_t len = 0;
+ if (inSignalContext) {
+ BUG_WARN_MSG(inSignalContext,
+ "Warning: attempting to log data in a signal unsafe "
+ "manner while in signal context. Please update to check "
+ "inSignalContext and/or use LogMessageVerbSigSafe() or "
+ "ErrorFSigSafe(). The offending log format message is:\n"
+ "%s\n", format);
+ return;
+ }
+
type_str = LogMessageTypeVerbString(type, verb);
if (!type_str)
return;
@@ -411,6 +514,44 @@ LogMessage(MessageType type, const char *format, ...)
va_end(ap);
}
+/* Log a message using only signal safe functions. */
+void
+LogMessageVerbSigSafe(MessageType type, int verb, const char *format, ...)
+{
+ va_list ap;
+ va_start(ap, format);
+ LogVMessageVerbSigSafe(type, verb, format, ap);
+ va_end(ap);
+}
+
+void
+LogVMessageVerbSigSafe(MessageType type, int verb, const char *format, va_list args)
+{
+ const char *type_str;
+ char buf[1024];
+ int len;
+ Bool newline;
+
+ type_str = LogMessageTypeVerbString(type, verb);
+ if (!type_str)
+ return;
+
+ /* if type_str is not "", prepend it and ' ', to message */
+ if (type_str[0] != '\0') {
+ LogSWrite(verb, type_str, strlen_sigsafe(type_str), FALSE);
+ LogSWrite(verb, " ", 1, FALSE);
+ }
+
+ len = pnprintf(buf, sizeof(buf), format, args);
+
+ /* Force '\n' at end of truncated line */
+ if (sizeof(buf) - len == 1)
+ buf[len - 1] = '\n';
+
+ newline = (buf[len - 1] == '\n');
+ LogSWrite(verb, buf, len, newline);
+}
+
void
LogVHdrMessageVerb(MessageType type, int verb, const char *msg_format,
va_list msg_args, const char *hdr_format, va_list hdr_args)
@@ -421,6 +562,16 @@ LogVHdrMessageVerb(MessageType type, int verb, const char *msg_format,
Bool newline;
size_t len = 0;
+ if (inSignalContext) {
+ BUG_WARN_MSG(inSignalContext,
+ "Warning: attempting to log data in a signal unsafe "
+ "manner while in signal context. Please update to check "
+ "inSignalContext and/or use LogMessageVerbSigSafe(). The "
+ "offending header and log message formats are:\n%s %s\n",
+ hdr_format, msg_format);
+ return;
+ }
+
type_str = LogMessageTypeVerbString(type, verb);
if (!type_str)
return;
@@ -649,6 +800,22 @@ ErrorF(const char *f, ...)
}
void
+VErrorFSigSafe(const char *f, va_list args)
+{
+ LogVMessageVerbSigSafe(X_ERROR, -1, f, args);
+}
+
+void
+ErrorFSigSafe(const char *f, ...)
+{
+ va_list args;
+
+ va_start(args, f);
+ VErrorFSigSafe(f, args);
+ va_end(args);
+}
+
+void
LogPrintMarkers(void)
{
/* Show what the message marker symbols mean. */
diff --git a/xorg-server/os/osinit.c b/xorg-server/os/osinit.c
index e2a220886..6cc040178 100644
--- a/xorg-server/os/osinit.c
+++ b/xorg-server/os/osinit.c
@@ -113,7 +113,7 @@ OsSigHandler(int signo)
const char *dlerr = dlerror();
if (dlerr) {
- LogMessage(X_ERROR, "Dynamic loader error: %s\n", dlerr);
+ LogMessageVerbSigSafe(X_ERROR, 1, "Dynamic loader error: %s\n", dlerr);
}
#endif /* RTLD_DI_SETSIGNAL */
@@ -129,8 +129,8 @@ OsSigHandler(int signo)
#ifdef SA_SIGINFO
if (sip->si_code == SI_USER) {
- ErrorF("Recieved signal %d sent by process %ld, uid %ld\n",
- signo, (long) sip->si_pid, (long) sip->si_uid);
+ ErrorFSigSafe("Recieved signal %u sent by process %u, uid %u\n", signo,
+ sip->si_pid, sip->si_uid);
}
else {
switch (signo) {
@@ -138,7 +138,7 @@ OsSigHandler(int signo)
case SIGBUS:
case SIGILL:
case SIGFPE:
- ErrorF("%s at address %p\n", strsignal(signo), sip->si_addr);
+ ErrorFSigSafe("%s at address %p\n", strsignal(signo), sip->si_addr);
}
}
#endif
diff --git a/xorg-server/os/utils.c b/xorg-server/os/utils.c
index 3a1ef9303..998c3ed4a 100644
--- a/xorg-server/os/utils.c
+++ b/xorg-server/os/utils.c
@@ -204,6 +204,8 @@ int auditTrailLevel = 1;
char *SeatId = NULL;
+sig_atomic_t inSignalContext = FALSE;
+
#if defined(SVR4) || defined(__linux__) || defined(CSRG_BASED)
#define HAS_SAVED_IDS_AND_SETEUID
#endif
@@ -1791,3 +1793,47 @@ xstrtokenize(const char *str, const char *separators)
free(list);
return NULL;
}
+
+/* Format a number into a string in a signal safe manner. The string should be
+ * at least 21 characters in order to handle all uint64_t values. */
+void
+FormatUInt64(uint64_t num, char *string)
+{
+ uint64_t divisor;
+ int len;
+ int i;
+
+ for (len = 1, divisor = 10;
+ len < 20 && num / divisor;
+ len++, divisor *= 10);
+
+ for (i = len, divisor = 1; i > 0; i--, divisor *= 10)
+ string[i - 1] = '0' + ((num / divisor) % 10);
+
+ string[len] = '\0';
+}
+
+/* Format a number into a hexadecimal string in a signal safe manner. The string
+ * should be at least 17 characters in order to handle all uint64_t values. */
+void
+FormatUInt64Hex(uint64_t num, char *string)
+{
+ uint64_t divisor;
+ int len;
+ int i;
+
+ for (len = 1, divisor = 0x10;
+ len < 16 && num / divisor;
+ len++, divisor *= 0x10);
+
+ for (i = len, divisor = 1; i > 0; i--, divisor *= 0x10) {
+ int val = (num / divisor) % 0x10;
+
+ if (val < 10)
+ string[i - 1] = '0' + val;
+ else
+ string[i - 1] = 'a' + val - 10;
+ }
+
+ string[len] = '\0';
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-29 17:29:43 +0000