From 688fb0e85551eb6f05e54c3df20ae325f4b88224 Mon Sep 17 00:00:00 2001

From: Jakub Filak <jfilak@redhat.com>

Date: Thu, 16 Apr 2015 11:17:20 +0200

Subject: [PATCH] lib: make the dump proc data functions more robust

dump_fd_info and dump_proc_diff are being called from processes running

under root permissions, so these functions must allow callers to

atomically created the destination file and update the ownership of that

file.

Related: #1211835

Signed-off-by: Jakub Filak <jfilak@redhat.com>

---

 src/include/internal_libreport.h |  2 ++

 src/lib/get_cmdline.c            | 29 ++++++++++++++++++++++++++---

 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/src/include/internal_libreport.h b/src/include/internal_libreport.h

index 11c18d9..99f2fe1 100644

--- a/src/include/internal_libreport.h

+++ b/src/include/internal_libreport.h

@@ -641,6 +641,8 @@ char* get_cwd(pid_t pid);

 char* get_rootdir(pid_t pid);

 #define get_fsuid libreport_get_fsuid

 int get_fsuid(const char *proc_pid_status);

+#define dump_fd_info_ext libreport_dump_fd_info_ext

+int dump_fd_info_ext(const char *dest_filename, const char *proc_pid_fd_path, uid_t uid, gid_t gid);

 #define dump_fd_info libreport_dump_fd_info

 int dump_fd_info(const char *dest_filename, const char *proc_pid_fd_path);

diff --git a/src/lib/get_cmdline.c b/src/lib/get_cmdline.c

index 2e362c5..c55de30 100644

--- a/src/lib/get_cmdline.c

+++ b/src/lib/get_cmdline.c

@@ -213,7 +213,7 @@ int get_fsuid(const char *proc_pid_status)

     return fs_uid;

 }

-int dump_fd_info(const char *dest_filename, const char *proc_pid_fd_path)

+int dump_fd_info_ext(const char *dest_filename, const char *proc_pid_fd_path, uid_t uid, gid_t gid)

 {

     DIR *proc_fd_dir = NULL;

     int proc_fdinfo_fd = -1;

@@ -237,7 +237,7 @@ int dump_fd_info(const char *dest_filename, const char *proc_pid_fd_path)

         goto dumpfd_cleanup;

     }

-    stream = fopen(dest_filename, "w");

+    stream = fopen(dest_filename, "wex");

     if (!stream)

     {

         r = -ENOMEM;

@@ -295,7 +295,25 @@ dumpfd_next_fd:

 dumpfd_cleanup:

     errno = 0;

-    fclose(stream);

+

+    if (stream != NULL)

+    {

+        if (uid != (uid_t)-1L)

+        {

+            const int stream_fd = fileno(stream);

+            r = fchown(stream_fd, uid, gid);

+            if (r < 0)

+            {

+                perror_msg("Can't change '%s' ownership to %lu:%lu", dest_filename, (long)uid, (long)gid);

+                fclose(stream);

+                unlink(dest_filename);

+                stream = NULL;

+            }

+        }

+

+        if (stream != NULL)

+            fclose(stream);

+    }

     if (r == 0 && errno != 0)

         r = -errno;

@@ -306,3 +324,8 @@ dumpfd_cleanup:

     return r;

 }

+

+int dump_fd_info(const char *dest_filename, const char *proc_pid_fd_path)

+{

+    return dump_fd_info_ext(dest_filename, proc_pid_fd_path, /*UID*/-1, /*GID*/-1);

+}

-- 

2.1.0