ccpp hook: reanme it, and add "crash storm protection" (see rhbz#542003)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

6 files changed, 46 insertions, 16 deletions

diff --git a/.gitignore b/.gitignore
index e76499cc..b6f190c6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -50,6 +50,6 @@ src/Daemon/abrtd
 src/Gui/abrt.desktop
 src/Hooks/abrt_exception_handler.py
 src/Hooks/dumpoops
-src/Hooks/hookCCpp
+src/Hooks/abrt-hook-ccpp
 src/Hooks/abrt-pyhook-helper
 stamp-h1
diff --git a/abrt.spec b/abrt.spec
index cdbd0b65..65cd1b33 100644
--- a/abrt.spec
+++ b/abrt.spec
@@ -311,7 +311,7 @@ fi
 %defattr(-,root,root,-)
 %config(noreplace) %{_sysconfdir}/%{name}/plugins/CCpp.conf
 %{_libdir}/%{name}/libCCpp.so*
-%{_libexecdir}/hookCCpp
+%{_libexecdir}/abrt-hook-ccpp
 
 #%files plugin-firefox
 #%{_libdir}/%{name}/libFirefox.so*
diff --git a/doc/DESIGN b/doc/DESIGN
index 7298b4c8..207904cc 100644
--- a/doc/DESIGN
+++ b/doc/DESIGN
@@ -53,9 +53,9 @@ which processes it according to configuration in /etc/abrt/*.conf.
 
 In order to catch binary crashes, we install a handler for it
 in /proc/sys/kernel/core_pattern (by setting it to
-"|/usr/libexec/hookCCpp /var/cache/abrt %p %s %u").
+"|/usr/libexec/abrt-hook-ccpp /var/cache/abrt %p %s %u").
 When process dumps core, the dump is written into /var/cache/abrt/DIR.
-After this, hookCCpp spawns "abrt-process -d /var/cache/abrt/DIR"
+After this, abrt-hook-ccpp spawns "abrt-process -d /var/cache/abrt/DIR"
 and terminates.
 
 When python program crashes, it invokes internel python subroutine
diff --git a/lib/Plugins/Makefile.am b/lib/Plugins/Makefile.am
index 97da2204..58f1334d 100644
--- a/lib/Plugins/Makefile.am
+++ b/lib/Plugins/Makefile.am
@@ -52,7 +52,7 @@ libCCpp_la_SOURCES = CCpp.cpp CCpp.h
 libCCpp_la_LDFLAGS = -avoid-version
 libCCpp_la_LIBADD = $(NSS_LIBS)
 libCCpp_la_CPPFLAGS = -I$(srcdir)/../../inc -I$(srcdir)/../Utils \
-    -DCCPP_HOOK_PATH=\"${libexecdir}/hookCCpp\" \
+    -DCCPP_HOOK_PATH=\"${libexecdir}/abrt-hook-ccpp\" \
     -DDEBUG_DUMPS_DIR=\"$(DEBUG_DUMPS_DIR)\" \
     -DLOCALSTATEDIR='"$(localstatedir)"' \
     $(NSS_CFLAGS)
@@ -63,7 +63,7 @@ libCCpp_la_CPPFLAGS = -I$(srcdir)/../../inc -I$(srcdir)/../Utils \
 #libFirefox_la_LDFLAGS = -avoid-version
 #libFirefox_la_LIBADD = $(NSS_LIBS)
 #libFirefox_la_CPPFLAGS = -I$(srcdir)/../../inc -I$(srcdir)/../Utils \
-#    -DCCPP_HOOK_PATH=\"${libexecdir}/hookCCpp\" \
+#    -DCCPP_HOOK_PATH=\"${libexecdir}/abrt-hook-ccpp\" \
 #    -DDEBUG_DUMPS_DIR=\"$(DEBUG_DUMPS_DIR)\" \
 #    -DLOCALSTATEDIR='"$(localstatedir)"' \
 #    $(NSS_CFLAGS)
diff --git a/src/Hooks/CCpp.cpp b/src/Hooks/CCpp.cpp
index 78a24711..ea616860 100644
--- a/src/Hooks/CCpp.cpp
+++ b/src/Hooks/CCpp.cpp
@@ -190,6 +190,9 @@ static int daemon_is_ok()
 
 int main(int argc, char** argv)
 {
+    int fd;
+    struct stat sb;
+
     const char* program_name = argv[0];
     if (argc < 4)
     {
@@ -238,7 +241,7 @@ int main(int argc, char** argv)
         {
             error_msg_and_die("can't read /proc/%u/exe link", (int)pid);
         }
-        if (strstr(executable, "/hookCCpp"))
+        if (strstr(executable, "/abrt-hook-ccpp"))
         {
             error_msg_and_die("pid %u is '%s', not dumping it to avoid recursion",
                             (int)pid, executable);
@@ -246,12 +249,40 @@ int main(int argc, char** argv)
 
         char path[PATH_MAX];
 
+        /* Check /var/cache/abrt/last-ccpp marker, do not dump repeated crashes
+         * if they happen too often. Else, write new marker value.
+         */
+        snprintf(path, sizeof(path), "%s/last-ccpp", dddir);
+        fd = open(path, O_RDWR | O_CREAT, 0666);
+        if (fd >= 0)
+        {
+            int sz;
+            fstat(fd, &sb); /* !paranoia. this can't fail. */
+
+            if (sb.st_size != 0 /* if it wasn't created by us just now... */
+	     && (unsigned)(time(NULL) - sb.st_mtime) < 20 /* and is relatively new [is 20 sec ok?] */
+            ) {
+                sz = read(fd, path, sizeof(path)-1); /* (ab)using path as scratch buf */
+                if (sz > 0)
+                {
+                    path[sz] = '\0';
+                    if (strcmp(executable, path) == 0)
+                        error_msg_and_die("not dumping repeating crash in '%s'", executable);
+                }
+                lseek(fd, 0, SEEK_SET);
+            }
+            sz = write(fd, executable, strlen(executable));
+            if (sz >= 0)
+                ftruncate(fd, sz);
+            close(fd);
+        }
+
         if (strstr(executable, "/abrtd"))
         {
             /* If abrtd crashes, we don't want to create a _directory_,
              * since that can make new copy of abrtd to process it,
              * and maybe crash again...
-             * On the contrary, mere files are ignored by abrtd.
+             * Unlike dirs, mere files are ignored by abrtd.
              */
             snprintf(path, sizeof(path), "%s/abrtd-coredump", dddir);
             core_fd = xopen3(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
@@ -263,7 +294,7 @@ int main(int argc, char** argv)
                  * but it does not log file name */
                 error_msg_and_die("error saving coredump to %s", path);
             }
-            log("saved core dump of pid %u to %s (%llu bytes)", (int)pid, path, (long long)size);
+            log("saved core dump of pid %u (%s) to %s (%llu bytes)", (int)pid, executable, path, (long long)size);
             return 0;
         }
 
@@ -306,9 +337,9 @@ int main(int argc, char** argv)
         }
         lseek(core_fd, 0, SEEK_SET);
         /* note: core_fd is still open, we may use it later to copy core to user's dir */
+        log("saved core dump of pid %u (%s) to %s (%llu bytes)", (int)pid, executable, path, (long long)size);
         free(executable);
         free(cmdline);
-        log("saved core dump of pid %u to %s (%llu bytes)", (int)pid, path, (long long)size);
         path[len] = '\0'; /* path now contains directory name */
 
         /* We close dumpdir before we start catering for crash storm case.
@@ -430,7 +461,7 @@ int main(int argc, char** argv)
     /* Mimic "core.PID" if requested */
     char core_basename[sizeof("core.%u") + sizeof(int)*3] = "core";
     char buf[] = "0\n";
-    int fd = open("/proc/sys/kernel/core_uses_pid", O_RDONLY);
+    fd = open("/proc/sys/kernel/core_uses_pid", O_RDONLY);
     if (fd >= 0)
     {
         read(fd, buf, sizeof(buf));
@@ -475,7 +506,6 @@ int main(int argc, char** argv)
     /* Do not O_TRUNC: if later checks fail, we do not want to have file already modified here */
     errno = 0;
     int usercore_fd = open(core_basename, O_WRONLY | O_CREAT | O_NOFOLLOW, 0600); /* kernel makes 0600 too */
-    struct stat sb;
     if (usercore_fd < 0
      || fstat(usercore_fd, &sb) != 0
      || !S_ISREG(sb.st_mode)
diff --git a/src/Hooks/Makefile.am b/src/Hooks/Makefile.am
index c643b248..21569570 100644
--- a/src/Hooks/Makefile.am
+++ b/src/Hooks/Makefile.am
@@ -1,17 +1,17 @@
-libexec_PROGRAMS = hookCCpp
+libexec_PROGRAMS = abrt-hook-ccpp
 bin_PROGRAMS = dumpoops abrt-pyhook-helper
 
 # CCpp
-hookCCpp_SOURCES = \
+abrt_hook_ccpp_SOURCES = \
     CCpp.cpp
-hookCCpp_CPPFLAGS = \
+abrt_hook_ccpp_CPPFLAGS = \
     -I$(srcdir)/../../inc \
     -I$(srcdir)/../../lib/Utils \
     -DDEBUG_DUMPS_DIR=\"$(DEBUG_DUMPS_DIR)\" \
     -DCONF_DIR=\"$(CONF_DIR)\" \
     -DVAR_RUN=\"$(VAR_RUN)\" \
     -D_GNU_SOURCE
-hookCCpp_LDADD = \
+abrt_hook_ccpp_LDADD = \
     ../../lib/Utils/libABRTUtils.la
 
 # dumpoops