From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 9 Apr 2024 15:51:54 +0000 (+0200)
Subject: sd-journal: make sure sd_journal_add_match() also accepts SIZE_MAX as size
X-Git-Tag: v256-rc1~246
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e1771c8ee63f1ce5c3febfdba27089b361f7cf4e;p=thirdparty%2Fsystemd.git

sd-journal: make sure sd_journal_add_match() also accepts SIZE_MAX as size

In many of our internal functions that take a pointer + a size we have
introduced the rule that SIZE_MAX as size means: take strlen().

sd_journal_add_match() has something similar, but the special value is
0, not SIZE_MAX. This is a bit ugly, since a zero size data block is
theoretically fine. The only reason sd_journal_add_match() gets away
with using this special value is because valid matches must consist of
at least 2 chars, hence cannot be zero.

But let's make this more robust and less surprising when compared to the
rest of our code, and *also* accept SIZE_MAX to mean strlen().

No actual code changes, just some clean-up.
---

diff --git a/src/coredump/coredumpctl.c b/src/coredump/coredumpctl.c
index fe74c77e484..3a3cd7dca2b 100644
--- a/src/coredump/coredumpctl.c
+++ b/src/coredump/coredumpctl.c
@@ -95,7 +95,7 @@ static int add_match(sd_journal *j, const char *match) {
         if (field)
                 r = journal_add_match_pair(j, field, match);
         else
-                r = sd_journal_add_match(j, match, 0);
+                r = sd_journal_add_match(j, match, SIZE_MAX);
         if (r < 0)
                 return log_error_errno(r, "Failed to add match \"%s%s%s\": %m",
                                        strempty(field), field ? "=" : "", match);
@@ -106,11 +106,11 @@ static int add_match(sd_journal *j, const char *match) {
 static int add_matches(sd_journal *j, char **matches) {
         int r;
 
-        r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR, 0);
+        r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR, SIZE_MAX);
         if (r < 0)
                 return log_error_errno(r, "Failed to add match \"%s\": %m", "MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR);
 
-        r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR, 0);
+        r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR, SIZE_MAX);
         if (r < 0)
                 return log_error_errno(r, "Failed to add match \"%s\": %m", "MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR);
 
diff --git a/src/journal/bsod.c b/src/journal/bsod.c
index a4788b828cf..0da0df9ee70 100644
--- a/src/journal/bsod.c
+++ b/src/journal/bsod.c
@@ -75,12 +75,12 @@ static int acquire_first_emergency_log_message(char **ret) {
         if (r < 0)
                 return log_error_errno(r, "Failed to add boot ID filter: %m");
 
-        r = sd_journal_add_match(j, "_UID=0", 0);
+        r = sd_journal_add_match(j, "_UID=0", SIZE_MAX);
         if (r < 0)
                 return log_error_errno(r, "Failed to add User ID filter: %m");
 
         assert_cc(0 == LOG_EMERG);
-        r = sd_journal_add_match(j, "PRIORITY=0", 0);
+        r = sd_journal_add_match(j, "PRIORITY=0", SIZE_MAX);
         if (r < 0)
                 return log_error_errno(r, "Failed to add Emergency filter: %m");
 
diff --git a/src/journal/journalctl-filter.c b/src/journal/journalctl-filter.c
index 5f6118f586e..1fdde5eb379 100644
--- a/src/journal/journalctl-filter.c
+++ b/src/journal/journalctl-filter.c
@@ -69,7 +69,7 @@ static int add_dmesg(sd_journal *j) {
         if (!arg_dmesg)
                 return 0;
 
-        r = sd_journal_add_match(j, "_TRANSPORT=kernel", 0);
+        r = sd_journal_add_match(j, "_TRANSPORT=kernel", SIZE_MAX);
         if (r < 0)
                 return r;
 
@@ -440,7 +440,7 @@ static int add_matches(sd_journal *j, char **args) {
                         have_term = true;
 
                 } else {
-                        r = sd_journal_add_match(j, *i, 0);
+                        r = sd_journal_add_match(j, *i, SIZE_MAX);
                         if (r < 0)
                                 return log_error_errno(r, "Failed to add match '%s': %m", *i);
                         have_term = true;
diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index 383f3e5d572..a4ed3804d86 100644
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -233,7 +233,11 @@ _public_ int sd_journal_add_match(sd_journal *j, const void *data, size_t size)
         assert_return(!journal_origin_changed(j), -ECHILD);
         assert_return(data, -EINVAL);
 
-        if (size == 0)
+        /* If the size is unspecified, assume it's a string. Note: 0 is the public value we document for
+         * this, for historical reasons. Internally, we pretty widely started using SIZE_MAX for this in
+         * similar cases however, hence accept that too. And internally we actually prefer it, to make things
+         * less surprising. */
+        if (IN_SET(size, 0, SIZE_MAX))
                 size = strlen(data);
 
         if (!match_is_valid(data, size))
@@ -336,7 +340,7 @@ int journal_add_match_pair(sd_journal *j, const char *field, const char *value)
         if (!s)
                 return -ENOMEM;
 
-        return sd_journal_add_match(j, s, 0);
+        return sd_journal_add_match(j, s, SIZE_MAX);
 }
 
 int journal_add_matchf(sd_journal *j, const char *format, ...) {
@@ -353,7 +357,7 @@ int journal_add_matchf(sd_journal *j, const char *format, ...) {
         if (r < 0)
                 return -ENOMEM;
 
-        return sd_journal_add_match(j, s, 0);
+        return sd_journal_add_match(j, s, SIZE_MAX);
 }
 
 _public_ int sd_journal_add_conjunction(sd_journal *j) {
diff --git a/src/libsystemd/sd-journal/test-journal-enum.c b/src/libsystemd/sd-journal/test-journal-enum.c
index 93d4b8f3c74..d101fe76f21 100644
--- a/src/libsystemd/sd-journal/test-journal-enum.c
+++ b/src/libsystemd/sd-journal/test-journal-enum.c
@@ -17,8 +17,8 @@ int main(int argc, char *argv[]) {
 
         assert_se(sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY | SD_JOURNAL_ASSUME_IMMUTABLE) >= 0);
 
-        assert_se(sd_journal_add_match(j, "_TRANSPORT=syslog", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "_UID=0", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "_TRANSPORT=syslog", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "_UID=0", SIZE_MAX) >= 0);
 
         SD_JOURNAL_FOREACH_BACKWARDS(j) {
                 const void *d;
diff --git a/src/libsystemd/sd-journal/test-journal-match.c b/src/libsystemd/sd-journal/test-journal-match.c
index e56b27dde3f..c2c345fb07f 100644
--- a/src/libsystemd/sd-journal/test-journal-match.c
+++ b/src/libsystemd/sd-journal/test-journal-match.c
@@ -18,38 +18,38 @@ int main(int argc, char *argv[]) {
 
         assert_se(sd_journal_open(&j, SD_JOURNAL_ASSUME_IMMUTABLE) >= 0);
 
-        assert_se(sd_journal_add_match(j, "foobar", 0) < 0);
-        assert_se(sd_journal_add_match(j, "foobar=waldo", 0) < 0);
-        assert_se(sd_journal_add_match(j, "", 0) < 0);
-        assert_se(sd_journal_add_match(j, "=", 0) < 0);
-        assert_se(sd_journal_add_match(j, "=xxxxx", 0) < 0);
+        assert_se(sd_journal_add_match(j, "foobar", SIZE_MAX) < 0);
+        assert_se(sd_journal_add_match(j, "foobar=waldo", SIZE_MAX) < 0);
+        assert_se(sd_journal_add_match(j, "", SIZE_MAX) < 0);
+        assert_se(sd_journal_add_match(j, "=", SIZE_MAX) < 0);
+        assert_se(sd_journal_add_match(j, "=xxxxx", SIZE_MAX) < 0);
         assert_se(sd_journal_add_match(j, (uint8_t[4]){'A', '=', '\1', '\2'}, 4) >= 0);
         assert_se(sd_journal_add_match(j, (uint8_t[5]){'B', '=', 'C', '\0', 'D'}, 5) >= 0);
-        assert_se(sd_journal_add_match(j, "HALLO=WALDO", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "QUUX=mmmm", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "QUUX=xxxxx", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "HALLO=", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "QUUX=xxxxx", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "QUUX=yyyyy", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "PIFF=paff", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "HALLO=WALDO", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "QUUX=mmmm", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "QUUX=xxxxx", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "HALLO=", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "QUUX=xxxxx", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "QUUX=yyyyy", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "PIFF=paff", SIZE_MAX) >= 0);
 
         assert_se(sd_journal_add_disjunction(j) >= 0);
 
-        assert_se(sd_journal_add_match(j, "ONE=one", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "ONE=two", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "TWO=two", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "ONE=one", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "ONE=two", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "TWO=two", SIZE_MAX) >= 0);
 
         assert_se(sd_journal_add_conjunction(j) >= 0);
 
-        assert_se(sd_journal_add_match(j, "L4_1=yes", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "L4_1=ok", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "L4_2=yes", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "L4_2=ok", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "L4_1=yes", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "L4_1=ok", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "L4_2=yes", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "L4_2=ok", SIZE_MAX) >= 0);
 
         assert_se(sd_journal_add_disjunction(j) >= 0);
 
-        assert_se(sd_journal_add_match(j, "L3=yes", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "L3=ok", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "L3=yes", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "L3=ok", SIZE_MAX) >= 0);
 
         assert_se(t = journal_make_match_string(j));
 
diff --git a/src/libsystemd/sd-journal/test-journal-stream.c b/src/libsystemd/sd-journal/test-journal-stream.c
index cb245b2fbd4..00c0435fd4c 100644
--- a/src/libsystemd/sd-journal/test-journal-stream.c
+++ b/src/libsystemd/sd-journal/test-journal-stream.c
@@ -121,7 +121,7 @@ static void run_test(void) {
 
         assert_se(sd_journal_open_directory(&j, t, SD_JOURNAL_ASSUME_IMMUTABLE) >= 0);
 
-        assert_se(sd_journal_add_match(j, "MAGIC=quux", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "MAGIC=quux", SIZE_MAX) >= 0);
         SD_JOURNAL_FOREACH_BACKWARDS(j) {
                 _cleanup_free_ char *c;
 
@@ -147,7 +147,7 @@ static void run_test(void) {
         verify_contents(j, 1);
 
         printf("NEXT TEST\n");
-        assert_se(sd_journal_add_match(j, "MAGIC=quux", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "MAGIC=quux", SIZE_MAX) >= 0);
 
         assert_se(z = journal_make_match_string(j));
         printf("resulting match expression is: %s\n", z);
@@ -157,10 +157,10 @@ static void run_test(void) {
 
         printf("NEXT TEST\n");
         sd_journal_flush_matches(j);
-        assert_se(sd_journal_add_match(j, "MAGIC=waldo", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "NUMBER=10", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "NUMBER=11", 0) >= 0);
-        assert_se(sd_journal_add_match(j, "NUMBER=12", 0) >= 0);
+        assert_se(sd_journal_add_match(j, "MAGIC=waldo", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "NUMBER=10", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "NUMBER=11", SIZE_MAX) >= 0);
+        assert_se(sd_journal_add_match(j, "NUMBER=12", SIZE_MAX) >= 0);
 
         assert_se(z = journal_make_match_string(j));
         printf("resulting match expression is: %s\n", z);
diff --git a/src/shared/logs-show.c b/src/shared/logs-show.c
index ac2fb1ea6bd..e63be5002c8 100644
--- a/src/shared/logs-show.c
+++ b/src/shared/logs-show.c
@@ -1570,18 +1570,18 @@ int add_matches_for_unit(sd_journal *j, const char *unit) {
 
             /* Look for coredumps of the service */
             (r = sd_journal_add_disjunction(j)) ||
-            (r = sd_journal_add_match(j, "MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1", 0)) ||
-            (r = sd_journal_add_match(j, "_UID=0", 0)) ||
+            (r = sd_journal_add_match(j, "MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1", SIZE_MAX)) ||
+            (r = sd_journal_add_match(j, "_UID=0", SIZE_MAX)) ||
             (r = journal_add_match_pair(j, "COREDUMP_UNIT", unit)) ||
 
              /* Look for messages from PID 1 about this service */
             (r = sd_journal_add_disjunction(j)) ||
-            (r = sd_journal_add_match(j, "_PID=1", 0)) ||
+            (r = sd_journal_add_match(j, "_PID=1", SIZE_MAX)) ||
             (r = journal_add_match_pair(j, "UNIT", unit)) ||
 
             /* Look for messages from authorized daemons about this service */
             (r = sd_journal_add_disjunction(j)) ||
-            (r = sd_journal_add_match(j, "_UID=0", 0)) ||
+            (r = sd_journal_add_match(j, "_UID=0", SIZE_MAX)) ||
             (r = journal_add_match_pair(j, "OBJECT_SYSTEMD_UNIT", unit))
         );
 
@@ -1615,13 +1615,13 @@ int add_matches_for_user_unit(sd_journal *j, const char *unit, uid_t uid) {
                 (r = sd_journal_add_disjunction(j)) ||
                 (r = journal_add_match_pair(j, "COREDUMP_USER_UNIT", unit)) ||
                 (r = journal_add_matchf(j, "_UID="UID_FMT, uid)) ||
-                (r = sd_journal_add_match(j, "_UID=0", 0)) ||
+                (r = sd_journal_add_match(j, "_UID=0", SIZE_MAX)) ||
 
                 /* Look for messages from authorized daemons about this service */
                 (r = sd_journal_add_disjunction(j)) ||
                 (r = journal_add_match_pair(j, "OBJECT_SYSTEMD_USER_UNIT", unit)) ||
                 (r = journal_add_matchf(j, "_UID="UID_FMT, uid)) ||
-                (r = sd_journal_add_match(j, "_UID=0", 0))
+                (r = sd_journal_add_match(j, "_UID=0", SIZE_MAX))
         );
 
         if (r == 0 && endswith(unit, ".slice"))