diff options
Diffstat (limited to 'extra/polkit/polkit-101-CVE-2011-1485.patch')
| -rw-r--r-- | extra/polkit/polkit-101-CVE-2011-1485.patch | 909 |
1 files changed, 909 insertions, 0 deletions
diff --git a/extra/polkit/polkit-101-CVE-2011-1485.patch b/extra/polkit/polkit-101-CVE-2011-1485.patch new file mode 100644 index 000000000..8d0f81781 --- /dev/null +++ b/extra/polkit/polkit-101-CVE-2011-1485.patch @@ -0,0 +1,909 @@ +From dd848a42a64a3b22a0cc60f6657b56ce9b6010ae Mon Sep 17 00:00:00 2001 +From: David Zeuthen <davidz@redhat.com> +Date: Thu, 31 Mar 2011 16:59:09 +0000 +Subject: PolkitUnixProcess: Clarify that the real uid is returned, not the effective one + +On Linux, also switch to parsing /proc/<pid>/status instead of relying +on the st_uid returned by stat(2) to be the uid we want. + +This was pointed out by Neel Mehta <nmehta@google.com>. Thanks! + +Signed-off-by: David Zeuthen <davidz@redhat.com> +--- +diff --git a/src/polkit/polkitunixprocess.c b/src/polkit/polkitunixprocess.c +index d95a1d4..876da69 100644 +--- a/src/polkit/polkitunixprocess.c ++++ b/src/polkit/polkitunixprocess.c +@@ -24,9 +24,7 @@ + #endif + + #include <sys/types.h> +-#ifndef HAVE_FREEBSD +-#include <sys/stat.h> +-#else ++#ifdef HAVE_FREEBSD + #include <sys/param.h> + #include <sys/sysctl.h> + #include <sys/user.h> +@@ -34,6 +32,7 @@ + #include <stdlib.h> + #include <string.h> + #include <errno.h> ++#include <stdio.h> + + #include "polkitunixprocess.h" + #include "polkitsubject.h" +@@ -208,6 +207,8 @@ polkit_unix_process_get_pid (PolkitUnixProcess *process) + * + * Gets the uid of the owner of @process. + * ++ * Note that this returns the real user-id (not the effective user-id) of @process. ++ * + * Returns: The UNIX user id of the owner for @process or 0 if @error is set. + **/ + gint +@@ -215,17 +216,21 @@ polkit_unix_process_get_owner (PolkitUnixProcess *process, + GError **error) + { + gint result; ++ gchar *contents; ++ gchar **lines; + #ifdef HAVE_FREEBSD + struct kinfo_proc p; + #else +- struct stat statbuf; +- char procbuf[32]; ++ gchar filename[64]; ++ guint n; + #endif + + g_return_val_if_fail (POLKIT_IS_UNIX_PROCESS (process), 0); + g_return_val_if_fail (error == NULL || *error == NULL, 0); + + result = 0; ++ lines = NULL; ++ contents = NULL; + + #ifdef HAVE_FREEBSD + if (get_kinfo_proc (process->pid, &p) == 0) +@@ -241,23 +246,52 @@ polkit_unix_process_get_owner (PolkitUnixProcess *process, + + result = p.ki_uid; + #else +- g_snprintf (procbuf, sizeof procbuf, "/proc/%d", process->pid); +- if (stat (procbuf, &statbuf) != 0) ++ ++ /* see 'man proc' for layout of the status file ++ * ++ * Uid, Gid: Real, effective, saved set, and file system UIDs (GIDs). ++ */ ++ g_snprintf (filename, sizeof filename, "/proc/%d/status", process->pid); ++ if (!g_file_get_contents (filename, ++ &contents, ++ NULL, ++ error)) + { +- g_set_error (error, +- POLKIT_ERROR, +- POLKIT_ERROR_FAILED, +- "stat() failed for /proc/%d: %s", +- process->pid, +- g_strerror (errno)); + goto out; + } ++ lines = g_strsplit (contents, "\n", -1); ++ for (n = 0; lines != NULL && lines[n] != NULL; n++) ++ { ++ gint real_uid, effective_uid; ++ if (!g_str_has_prefix (lines[n], "Uid:")) ++ continue; ++ if (sscanf (lines[n] + 4, "%d %d", &real_uid, &effective_uid) != 2) ++ { ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "Unexpected line `%s' in file %s", ++ lines[n], ++ filename); ++ goto out; ++ } ++ else ++ { ++ result = real_uid; ++ goto out; ++ } ++ } + +- result = statbuf.st_uid; ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "Didn't find any line starting with `Uid:' in file %s", ++ filename); + #endif + +- out: +- ++out: ++ g_strfreev (lines); ++ g_free (contents); + return result; + } + +-- +cgit v0.8.3-6-g21f6 +From 129b6223a19e7fb2753f8cad7957ac5402394076 Mon Sep 17 00:00:00 2001 +From: David Zeuthen <davidz@redhat.com> +Date: Fri, 01 Apr 2011 16:09:45 +0000 +Subject: Make PolkitUnixProcess also record the uid of the process + +This is needed to avoid possible TOCTTOU issues since a process can +change both its real uid and effective uid. + +Signed-off-by: David Zeuthen <davidz@redhat.com> +--- +diff --git a/docs/polkit/polkit-1-sections.txt b/docs/polkit/polkit-1-sections.txt +index 12141e3..9f4fcf8 100644 +--- a/docs/polkit/polkit-1-sections.txt ++++ b/docs/polkit/polkit-1-sections.txt +@@ -145,10 +145,13 @@ POLKIT_UNIX_SESSION_GET_CLASS + PolkitUnixProcess + polkit_unix_process_new + polkit_unix_process_new_full ++polkit_unix_process_new_for_owner ++polkit_unix_process_set_pid + polkit_unix_process_get_pid ++polkit_unix_process_set_start_time + polkit_unix_process_get_start_time +-polkit_unix_process_set_pid +-polkit_unix_process_get_owner ++polkit_unix_process_set_uid ++polkit_unix_process_get_uid + <SUBSECTION Standard> + PolkitUnixProcessClass + POLKIT_UNIX_PROCESS +diff --git a/src/polkit/polkitsubject.c b/src/polkit/polkitsubject.c +index 577afec..d2c4c20 100644 +--- a/src/polkit/polkitsubject.c ++++ b/src/polkit/polkitsubject.c +@@ -238,13 +238,18 @@ polkit_subject_from_string (const gchar *str, + { + gint scanned_pid; + guint64 scanned_starttime; +- if (sscanf (str, "unix-process:%d:%" G_GUINT64_FORMAT, &scanned_pid, &scanned_starttime) == 2) ++ gint scanned_uid; ++ if (sscanf (str, "unix-process:%d:%" G_GUINT64_FORMAT ":%d", &scanned_pid, &scanned_starttime, &scanned_uid) == 3) ++ { ++ subject = polkit_unix_process_new_for_owner (scanned_pid, scanned_starttime, scanned_uid); ++ } ++ else if (sscanf (str, "unix-process:%d:%" G_GUINT64_FORMAT, &scanned_pid, &scanned_starttime) == 2) + { + subject = polkit_unix_process_new_full (scanned_pid, scanned_starttime); + } + else if (sscanf (str, "unix-process:%d", &scanned_pid) == 1) + { +- subject = polkit_unix_process_new_full (scanned_pid, 0); ++ subject = polkit_unix_process_new (scanned_pid); + if (polkit_unix_process_get_start_time (POLKIT_UNIX_PROCESS (subject)) == 0) + { + g_object_unref (subject); +@@ -297,6 +302,8 @@ polkit_subject_to_gvariant (PolkitSubject *subject) + g_variant_new_uint32 (polkit_unix_process_get_pid (POLKIT_UNIX_PROCESS (subject)))); + g_variant_builder_add (&builder, "{sv}", "start-time", + g_variant_new_uint64 (polkit_unix_process_get_start_time (POLKIT_UNIX_PROCESS (subject)))); ++ g_variant_builder_add (&builder, "{sv}", "uid", ++ g_variant_new_int32 (polkit_unix_process_get_uid (POLKIT_UNIX_PROCESS (subject)))); + } + else if (POLKIT_IS_UNIX_SESSION (subject)) + { +@@ -395,6 +402,7 @@ polkit_subject_new_for_gvariant (GVariant *variant, + GVariant *v; + guint32 pid; + guint64 start_time; ++ gint32 uid; + + v = lookup_asv (details_gvariant, "pid", G_VARIANT_TYPE_UINT32, error); + if (v == NULL) +@@ -414,7 +422,18 @@ polkit_subject_new_for_gvariant (GVariant *variant, + start_time = g_variant_get_uint64 (v); + g_variant_unref (v); + +- ret = polkit_unix_process_new_full (pid, start_time); ++ v = lookup_asv (details_gvariant, "uid", G_VARIANT_TYPE_INT32, error); ++ if (v != NULL) ++ { ++ uid = g_variant_get_int32 (v); ++ g_variant_unref (v); ++ } ++ else ++ { ++ uid = -1; ++ } ++ ++ ret = polkit_unix_process_new_for_owner (pid, start_time, uid); + } + else if (g_strcmp0 (kind, "unix-session") == 0) + { +diff --git a/src/polkit/polkitunixprocess.c b/src/polkit/polkitunixprocess.c +index 876da69..913be3a 100644 +--- a/src/polkit/polkitunixprocess.c ++++ b/src/polkit/polkitunixprocess.c +@@ -62,6 +62,7 @@ struct _PolkitUnixProcess + + gint pid; + guint64 start_time; ++ gint uid; + }; + + struct _PolkitUnixProcessClass +@@ -74,6 +75,7 @@ enum + PROP_0, + PROP_PID, + PROP_START_TIME, ++ PROP_UID + }; + + static void subject_iface_init (PolkitSubjectIface *subject_iface); +@@ -81,6 +83,9 @@ static void subject_iface_init (PolkitSubjectIface *subject_iface); + static guint64 get_start_time_for_pid (gint pid, + GError **error); + ++static gint _polkit_unix_process_get_owner (PolkitUnixProcess *process, ++ GError **error); ++ + #ifdef HAVE_FREEBSD + static gboolean get_kinfo_proc (gint pid, struct kinfo_proc *p); + #endif +@@ -92,6 +97,7 @@ G_DEFINE_TYPE_WITH_CODE (PolkitUnixProcess, polkit_unix_process, G_TYPE_OBJECT, + static void + polkit_unix_process_init (PolkitUnixProcess *unix_process) + { ++ unix_process->uid = -1; + } + + static void +@@ -108,6 +114,10 @@ polkit_unix_process_get_property (GObject *object, + g_value_set_int (value, unix_process->pid); + break; + ++ case PROP_UID: ++ g_value_set_int (value, unix_process->uid); ++ break; ++ + case PROP_START_TIME: + g_value_set_uint64 (value, unix_process->start_time); + break; +@@ -132,6 +142,14 @@ polkit_unix_process_set_property (GObject *object, + polkit_unix_process_set_pid (unix_process, g_value_get_int (value)); + break; + ++ case PROP_UID: ++ polkit_unix_process_set_uid (unix_process, g_value_get_int (value)); ++ break; ++ ++ case PROP_START_TIME: ++ polkit_unix_process_set_start_time (unix_process, g_value_get_uint64 (value)); ++ break; ++ + default: + G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); + break; +@@ -139,12 +157,39 @@ polkit_unix_process_set_property (GObject *object, + } + + static void ++polkit_unix_process_constructed (GObject *object) ++{ ++ PolkitUnixProcess *process = POLKIT_UNIX_PROCESS (object); ++ ++ /* sets start_time and uid in case they are unset */ ++ ++ if (process->start_time == 0) ++ process->start_time = get_start_time_for_pid (process->pid, NULL); ++ ++ if (process->uid == -1) ++ { ++ GError *error; ++ error = NULL; ++ process->uid = _polkit_unix_process_get_owner (process, &error); ++ if (error != NULL) ++ { ++ process->uid = -1; ++ g_error_free (error); ++ } ++ } ++ ++ if (G_OBJECT_CLASS (polkit_unix_process_parent_class)->constructed != NULL) ++ G_OBJECT_CLASS (polkit_unix_process_parent_class)->constructed (object); ++} ++ ++static void + polkit_unix_process_class_init (PolkitUnixProcessClass *klass) + { + GObjectClass *gobject_class = G_OBJECT_CLASS (klass); + + gobject_class->get_property = polkit_unix_process_get_property; + gobject_class->set_property = polkit_unix_process_set_property; ++ gobject_class->constructed = polkit_unix_process_constructed; + + /** + * PolkitUnixProcess:pid: +@@ -156,7 +201,7 @@ polkit_unix_process_class_init (PolkitUnixProcessClass *klass) + g_param_spec_int ("pid", + "Process ID", + "The UNIX process ID", +- -1, ++ 0, + G_MAXINT, + 0, + G_PARAM_CONSTRUCT | +@@ -166,6 +211,27 @@ polkit_unix_process_class_init (PolkitUnixProcessClass *klass) + G_PARAM_STATIC_NICK)); + + /** ++ * PolkitUnixProcess:uid: ++ * ++ * The UNIX user id of the process or -1 if unknown. ++ * ++ * Note that this is the real user-id, not the effective user-id. ++ */ ++ g_object_class_install_property (gobject_class, ++ PROP_UID, ++ g_param_spec_int ("uid", ++ "User ID", ++ "The UNIX user ID", ++ -1, ++ G_MAXINT, ++ -1, ++ G_PARAM_CONSTRUCT | ++ G_PARAM_READWRITE | ++ G_PARAM_STATIC_NAME | ++ G_PARAM_STATIC_BLURB | ++ G_PARAM_STATIC_NICK)); ++ ++ /** + * PolkitUnixProcess:start-time: + * + * The start time of the process. +@@ -178,7 +244,8 @@ polkit_unix_process_class_init (PolkitUnixProcessClass *klass) + 0, + G_MAXUINT64, + 0, +- G_PARAM_READABLE | ++ G_PARAM_CONSTRUCT | ++ G_PARAM_READWRITE | + G_PARAM_STATIC_NAME | + G_PARAM_STATIC_BLURB | + G_PARAM_STATIC_NICK)); +@@ -186,113 +253,50 @@ polkit_unix_process_class_init (PolkitUnixProcessClass *klass) + } + + /** +- * polkit_unix_process_get_pid: ++ * polkit_unix_process_get_uid: + * @process: A #PolkitUnixProcess. + * +- * Gets the process id for @process. ++ * Gets the user id for @process. Note that this is the real user-id, ++ * not the effective user-id. + * +- * Returns: The process id for @process. ++ * Returns: The user id for @process or -1 if unknown. + */ + gint +-polkit_unix_process_get_pid (PolkitUnixProcess *process) ++polkit_unix_process_get_uid (PolkitUnixProcess *process) + { +- g_return_val_if_fail (POLKIT_IS_UNIX_PROCESS (process), 0); +- return process->pid; ++ g_return_val_if_fail (POLKIT_IS_UNIX_PROCESS (process), -1); ++ return process->uid; + } + + /** +- * polkit_unix_process_get_owner: ++ * polkit_unix_process_set_uid: + * @process: A #PolkitUnixProcess. +- * @error: (allow-none): Return location for error or %NULL. ++ * @uid: The user id to set for @process or -1 to unset it. + * +- * Gets the uid of the owner of @process. ++ * Sets the (real, not effective) user id for @process. ++ */ ++void ++polkit_unix_process_set_uid (PolkitUnixProcess *process, ++ gint uid) ++{ ++ g_return_if_fail (POLKIT_IS_UNIX_PROCESS (process)); ++ g_return_if_fail (uid >= -1); ++ process->uid = uid; ++} ++ ++/** ++ * polkit_unix_process_get_pid: ++ * @process: A #PolkitUnixProcess. + * +- * Note that this returns the real user-id (not the effective user-id) of @process. ++ * Gets the process id for @process. + * +- * Returns: The UNIX user id of the owner for @process or 0 if @error is set. +- **/ ++ * Returns: The process id for @process. ++ */ + gint +-polkit_unix_process_get_owner (PolkitUnixProcess *process, +- GError **error) ++polkit_unix_process_get_pid (PolkitUnixProcess *process) + { +- gint result; +- gchar *contents; +- gchar **lines; +-#ifdef HAVE_FREEBSD +- struct kinfo_proc p; +-#else +- gchar filename[64]; +- guint n; +-#endif +- + g_return_val_if_fail (POLKIT_IS_UNIX_PROCESS (process), 0); +- g_return_val_if_fail (error == NULL || *error == NULL, 0); +- +- result = 0; +- lines = NULL; +- contents = NULL; +- +-#ifdef HAVE_FREEBSD +- if (get_kinfo_proc (process->pid, &p) == 0) +- { +- g_set_error (error, +- POLKIT_ERROR, +- POLKIT_ERROR_FAILED, +- "get_kinfo_proc() failed for pid %d: %s", +- process->pid, +- g_strerror (errno)); +- goto out; +- } +- +- result = p.ki_uid; +-#else +- +- /* see 'man proc' for layout of the status file +- * +- * Uid, Gid: Real, effective, saved set, and file system UIDs (GIDs). +- */ +- g_snprintf (filename, sizeof filename, "/proc/%d/status", process->pid); +- if (!g_file_get_contents (filename, +- &contents, +- NULL, +- error)) +- { +- goto out; +- } +- lines = g_strsplit (contents, "\n", -1); +- for (n = 0; lines != NULL && lines[n] != NULL; n++) +- { +- gint real_uid, effective_uid; +- if (!g_str_has_prefix (lines[n], "Uid:")) +- continue; +- if (sscanf (lines[n] + 4, "%d %d", &real_uid, &effective_uid) != 2) +- { +- g_set_error (error, +- POLKIT_ERROR, +- POLKIT_ERROR_FAILED, +- "Unexpected line `%s' in file %s", +- lines[n], +- filename); +- goto out; +- } +- else +- { +- result = real_uid; +- goto out; +- } +- } +- +- g_set_error (error, +- POLKIT_ERROR, +- POLKIT_ERROR_FAILED, +- "Didn't find any line starting with `Uid:' in file %s", +- filename); +-#endif +- +-out: +- g_strfreev (lines); +- g_free (contents); +- return result; ++ return process->pid; + } + + /** +@@ -311,6 +315,21 @@ polkit_unix_process_get_start_time (PolkitUnixProcess *process) + } + + /** ++ * polkit_unix_process_set_start_time: ++ * @process: A #PolkitUnixProcess. ++ * @start_time: The start time for @pid. ++ * ++ * Set the start time of @process. ++ */ ++void ++polkit_unix_process_set_start_time (PolkitUnixProcess *process, ++ guint64 start_time) ++{ ++ g_return_if_fail (POLKIT_IS_UNIX_PROCESS (process)); ++ process->start_time = start_time; ++} ++ ++/** + * polkit_unix_process_set_pid: + * @process: A #PolkitUnixProcess. + * @pid: A process id. +@@ -323,18 +342,17 @@ polkit_unix_process_set_pid (PolkitUnixProcess *process, + { + g_return_if_fail (POLKIT_IS_UNIX_PROCESS (process)); + process->pid = pid; +- if (pid != (gint) -1) +- process->start_time = get_start_time_for_pid (pid, NULL); + } + + /** + * polkit_unix_process_new: + * @pid: The process id. + * +- * Creates a new #PolkitUnixProcess for @pid. The start time of the +- * process will be looked up in using e.g. the +- * <filename>/proc</filename> filesystem depending on the platform in +- * use. ++ * Creates a new #PolkitUnixProcess for @pid. ++ * ++ * The uid and start time of the process will be looked up in using ++ * e.g. the <filename>/proc</filename> filesystem depending on the ++ * platform in use. + * + * Returns: (transfer full): A #PolkitSubject. Free with g_object_unref(). + */ +@@ -353,22 +371,42 @@ polkit_unix_process_new (gint pid) + * + * Creates a new #PolkitUnixProcess object for @pid and @start_time. + * ++ * The uid of the process will be looked up in using e.g. the ++ * <filename>/proc</filename> filesystem depending on the platform in ++ * use. ++ * + * Returns: (transfer full): A #PolkitSubject. Free with g_object_unref(). + */ + PolkitSubject * + polkit_unix_process_new_full (gint pid, + guint64 start_time) + { +- PolkitUnixProcess *process; +- +- process = POLKIT_UNIX_PROCESS (polkit_unix_process_new ((gint) -1)); +- process->pid = pid; +- if (start_time != 0) +- process->start_time = start_time; +- else +- process->start_time = get_start_time_for_pid (pid, NULL); ++ return POLKIT_SUBJECT (g_object_new (POLKIT_TYPE_UNIX_PROCESS, ++ "pid", pid, ++ "start_time", start_time, ++ NULL)); ++} + +- return POLKIT_SUBJECT (process); ++/** ++ * polkit_unix_process_new_for_owner: ++ * @pid: The process id. ++ * @start_time: The start time for @pid or 0 to look it up in e.g. <filename>/proc</filename>. ++ * @uid: The (real, not effective) uid of the owner of @pid or -1 to look it up in e.g. <filename>/proc</filename>. ++ * ++ * Creates a new #PolkitUnixProcess object for @pid, @start_time and @uid. ++ * ++ * Returns: (transfer full): A #PolkitSubject. Free with g_object_unref(). ++ */ ++PolkitSubject * ++polkit_unix_process_new_for_owner (gint pid, ++ guint64 start_time, ++ gint uid) ++{ ++ return POLKIT_SUBJECT (g_object_new (POLKIT_TYPE_UNIX_PROCESS, ++ "pid", pid, ++ "start_time", start_time, ++ "uid", uid, ++ NULL)); + } + + static guint +@@ -616,3 +654,95 @@ out: + + return start_time; + } ++ ++static gint ++_polkit_unix_process_get_owner (PolkitUnixProcess *process, ++ GError **error) ++{ ++ gint result; ++ gchar *contents; ++ gchar **lines; ++#ifdef HAVE_FREEBSD ++ struct kinfo_proc p; ++#else ++ gchar filename[64]; ++ guint n; ++#endif ++ ++ g_return_val_if_fail (POLKIT_IS_UNIX_PROCESS (process), 0); ++ g_return_val_if_fail (error == NULL || *error == NULL, 0); ++ ++ result = 0; ++ lines = NULL; ++ contents = NULL; ++ ++#ifdef HAVE_FREEBSD ++ if (get_kinfo_proc (process->pid, &p) == 0) ++ { ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "get_kinfo_proc() failed for pid %d: %s", ++ process->pid, ++ g_strerror (errno)); ++ goto out; ++ } ++ ++ result = p.ki_uid; ++#else ++ ++ /* see 'man proc' for layout of the status file ++ * ++ * Uid, Gid: Real, effective, saved set, and file system UIDs (GIDs). ++ */ ++ g_snprintf (filename, sizeof filename, "/proc/%d/status", process->pid); ++ if (!g_file_get_contents (filename, ++ &contents, ++ NULL, ++ error)) ++ { ++ goto out; ++ } ++ lines = g_strsplit (contents, "\n", -1); ++ for (n = 0; lines != NULL && lines[n] != NULL; n++) ++ { ++ gint real_uid, effective_uid; ++ if (!g_str_has_prefix (lines[n], "Uid:")) ++ continue; ++ if (sscanf (lines[n] + 4, "%d %d", &real_uid, &effective_uid) != 2) ++ { ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "Unexpected line `%s' in file %s", ++ lines[n], ++ filename); ++ goto out; ++ } ++ else ++ { ++ result = real_uid; ++ goto out; ++ } ++ } ++ ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "Didn't find any line starting with `Uid:' in file %s", ++ filename); ++#endif ++ ++out: ++ g_strfreev (lines); ++ g_free (contents); ++ return result; ++} ++ ++/* deprecated public method */ ++gint ++polkit_unix_process_get_owner (PolkitUnixProcess *process, ++ GError **error) ++{ ++ return _polkit_unix_process_get_owner (process, error); ++} +diff --git a/src/polkit/polkitunixprocess.h b/src/polkit/polkitunixprocess.h +index b88cd03..531a57d 100644 +--- a/src/polkit/polkitunixprocess.h ++++ b/src/polkit/polkitunixprocess.h +@@ -47,16 +47,24 @@ typedef struct _PolkitUnixProcess PolkitUnixProcess; + typedef struct _PolkitUnixProcessClass PolkitUnixProcessClass; + + GType polkit_unix_process_get_type (void) G_GNUC_CONST; +-PolkitSubject *polkit_unix_process_new (gint pid); +-PolkitSubject *polkit_unix_process_new_full (gint pid, +- guint64 start_time); +- ++PolkitSubject *polkit_unix_process_new (gint pid); ++PolkitSubject *polkit_unix_process_new_full (gint pid, ++ guint64 start_time); ++PolkitSubject *polkit_unix_process_new_for_owner (gint pid, ++ guint64 start_time, ++ gint uid); + gint polkit_unix_process_get_pid (PolkitUnixProcess *process); + guint64 polkit_unix_process_get_start_time (PolkitUnixProcess *process); ++gint polkit_unix_process_get_uid (PolkitUnixProcess *process); + void polkit_unix_process_set_pid (PolkitUnixProcess *process, + gint pid); ++void polkit_unix_process_set_uid (PolkitUnixProcess *process, ++ gint uid); ++void polkit_unix_process_set_start_time (PolkitUnixProcess *process, ++ guint64 start_time); ++ + gint polkit_unix_process_get_owner (PolkitUnixProcess *process, +- GError **error); ++ GError **error) G_GNUC_DEPRECATED_FOR (polkit_unix_process_get_uid); + + G_END_DECLS + +-- +cgit v0.8.3-6-g21f6 +From c23d74447c7615dc74dae259f0fc3688ec988867 Mon Sep 17 00:00:00 2001 +From: David Zeuthen <davidz@redhat.com> +Date: Fri, 01 Apr 2011 16:12:27 +0000 +Subject: Use polkit_unix_process_get_uid() to get the owner of a process + +This avoids a TOCTTOU problem. + +Signed-off-by: David Zeuthen <davidz@redhat.com> +--- +diff --git a/src/polkitbackend/polkitbackendsessionmonitor.c b/src/polkitbackend/polkitbackendsessionmonitor.c +index 495f752..9c331b6 100644 +--- a/src/polkitbackend/polkitbackendsessionmonitor.c ++++ b/src/polkitbackend/polkitbackendsessionmonitor.c +@@ -293,14 +293,15 @@ polkit_backend_session_monitor_get_user_for_subject (PolkitBackendSessionMonitor + + if (POLKIT_IS_UNIX_PROCESS (subject)) + { +- local_error = NULL; +- uid = polkit_unix_process_get_owner (POLKIT_UNIX_PROCESS (subject), &local_error); +- if (local_error != NULL) ++ uid = polkit_unix_process_get_uid (POLKIT_UNIX_PROCESS (subject)); ++ if ((gint) uid == -1) + { +- g_propagate_prefixed_error (error, local_error, "Error getting user for process: "); ++ g_set_error (error, ++ POLKIT_ERROR, ++ POLKIT_ERROR_FAILED, ++ "Unix process subject does not have uid set"); + goto out; + } +- + ret = polkit_unix_user_new (uid); + } + else if (POLKIT_IS_SYSTEM_BUS_NAME (subject)) +-- +cgit v0.8.3-6-g21f6 +From 3b12cfac29dddd27f1f166a7574d8374cc1dccf2 Mon Sep 17 00:00:00 2001 +From: David Zeuthen <davidz@redhat.com> +Date: Fri, 01 Apr 2011 16:13:15 +0000 +Subject: pkexec: Avoid TOCTTOU problems with parent process + +In a nutshell, the parent process may change its uid (either real- or +effective uid) after launching pkexec. It can do this by exec()'ing +e.g. a setuid root program. + +To avoid this problem, just use the uid the parent process had when it +executed pkexec. This happens to be the same uid of the pkexec process +itself. + +Additionally, remove some dubious code that allowed pkexec to continue +when the parent process died as there is no reason to support +something like that. Also ensure that the pkexec process is killed if +the parent process dies. + +This problem was pointed out by Neel Mehta <nmehta@google.com>. + +Signed-off-by: David Zeuthen <davidz@redhat.com> +--- +diff --git a/src/programs/pkexec.c b/src/programs/pkexec.c +index 9217954..3e656be 100644 +--- a/src/programs/pkexec.c ++++ b/src/programs/pkexec.c +@@ -35,6 +35,10 @@ + #include <pwd.h> + #include <errno.h> + ++#ifdef __linux__ ++#include <sys/prctl.h> ++#endif ++ + #include <glib/gi18n.h> + + #ifdef POLKIT_AUTHFW_PAM +@@ -423,7 +427,6 @@ main (int argc, char *argv[]) + GPtrArray *saved_env; + gchar *opt_user; + pid_t pid_of_caller; +- uid_t uid_of_caller; + gpointer local_agent_handle; + + ret = 127; +@@ -598,40 +601,49 @@ main (int argc, char *argv[]) + */ + g_type_init (); + +- /* now check if the program that invoked us is authorized */ ++ /* make sure we are nuked if the parent process dies */ ++#ifdef __linux__ ++ if (prctl (PR_SET_PDEATHSIG, SIGTERM) != 0) ++ { ++ g_printerr ("prctl(PR_SET_PDEATHSIG, SIGTERM) failed: %s\n", g_strerror (errno)); ++ goto out; ++ } ++#else ++#warning "Please add OS specific code to catch when the parent dies" ++#endif ++ ++ /* Figure out the parent process */ + pid_of_caller = getppid (); + if (pid_of_caller == 1) + { + /* getppid() can return 1 if the parent died (meaning that we are reaped +- * by /sbin/init); get process group leader instead - for example, this +- * happens when launching via gnome-panel (alt+f2, then 'pkexec gedit'). ++ * by /sbin/init); In that case we simpy bail. + */ +- pid_of_caller = getpgrp (); +- } +- +- subject = polkit_unix_process_new (pid_of_caller); +- if (subject == NULL) +- { +- g_printerr ("No such process for pid %d: %s\n", (gint) pid_of_caller, error->message); +- g_error_free (error); ++ g_printerr ("Refusing to render service to dead parents.\n"); + goto out; + } + +- /* paranoia: check that the uid of pid_of_caller matches getuid() */ +- error = NULL; +- uid_of_caller = polkit_unix_process_get_owner (POLKIT_UNIX_PROCESS (subject), +- &error); +- if (error != NULL) +- { +- g_printerr ("Error determing pid of caller (pid %d): %s\n", (gint) pid_of_caller, error->message); +- g_error_free (error); +- goto out; +- } +- if (uid_of_caller != getuid ()) +- { +- g_printerr ("User of caller (%d) does not match our uid (%d)\n", uid_of_caller, getuid ()); +- goto out; +- } ++ /* This process we want to check an authorization for is the process ++ * that launched us - our parent process. ++ * ++ * At the time the parent process fork()'ed and exec()'ed us, the ++ * process had the same real-uid that we have now. So we use this ++ * real-uid instead of of looking it up to avoid TOCTTOU issues ++ * (consider the parent process exec()'ing a setuid helper). ++ * ++ * On the other hand, the monotonic process start-time is guaranteed ++ * to never change so it's safe to look that up given only the PID ++ * since we are guaranteed to be nuked if the parent goes away ++ * (cf. the prctl(2) call above). ++ */ ++ subject = polkit_unix_process_new_for_owner (pid_of_caller, ++ 0, /* 0 means "look up start-time in /proc" */ ++ getuid ()); ++ /* really double-check the invariants guaranteed by the PolkitUnixProcess class */ ++ g_assert (subject != NULL); ++ g_assert (polkit_unix_process_get_pid (POLKIT_UNIX_PROCESS (subject)) == pid_of_caller); ++ g_assert (polkit_unix_process_get_uid (POLKIT_UNIX_PROCESS (subject)) >= 0); ++ g_assert (polkit_unix_process_get_start_time (POLKIT_UNIX_PROCESS (subject)) > 0); + + error = NULL; + authority = polkit_authority_get_sync (NULL /* GCancellable* */, &error); +-- +cgit v0.8.3-6-g21f6 + |