Check seteuid return values in all cases

This commit is contained in:
Jakub Jelen 2017-02-07 15:34:01 +01:00
parent bdb932c46a
commit 465b6e6b82
3 changed files with 40 additions and 29 deletions

View File

@ -115,7 +115,8 @@ Patch201: openssh-7.1p2-audit-race-condition.patch
# make it build reusing the openssh sources # make it build reusing the openssh sources
Patch300: pam_ssh_agent_auth-0.9.3-build.patch Patch300: pam_ssh_agent_auth-0.9.3-build.patch
# check return value of seteuid() # check return value of seteuid()
Patch301: pam_ssh_agent_auth-0.9.2-seteuid.patch # https://sourceforge.net/p/pamsshagentauth/bugs/23/
Patch301: pam_ssh_agent_auth-0.10.3-seteuid.patch
# explicitly make pam callbacks visible # explicitly make pam callbacks visible
Patch302: pam_ssh_agent_auth-0.9.2-visibility.patch Patch302: pam_ssh_agent_auth-0.9.2-visibility.patch
# update to current version of agent structure # update to current version of agent structure
@ -403,7 +404,7 @@ The module is most useful for su and sudo service stacks.
%if %{pam_ssh_agent} %if %{pam_ssh_agent}
pushd pam_ssh_agent_auth-%{pam_ssh_agent_ver} pushd pam_ssh_agent_auth-%{pam_ssh_agent_ver}
%patch300 -p2 -b .psaa-build %patch300 -p2 -b .psaa-build
%patch301 -p1 -b .psaa-seteuid %patch301 -p2 -b .psaa-seteuid
%patch302 -p2 -b .psaa-visibility %patch302 -p2 -b .psaa-visibility
%patch306 -p2 -b .psaa-compat %patch306 -p2 -b .psaa-compat
%patch305 -p2 -b .psaa-agent %patch305 -p2 -b .psaa-agent

View File

@ -0,0 +1,37 @@
diff -up openssh-7.4p1/pam_ssh_agent_auth-0.10.3/iterate_ssh_agent_keys.c.psaa-seteuid openssh-7.4p1/pam_ssh_agent_auth-0.10.3/iterate_ssh_agent_keys.c
--- openssh-7.4p1/pam_ssh_agent_auth-0.10.3/iterate_ssh_agent_keys.c.psaa-seteuid 2017-02-07 15:41:53.172334151 +0100
+++ openssh-7.4p1/pam_ssh_agent_auth-0.10.3/iterate_ssh_agent_keys.c 2017-02-07 15:41:53.174334149 +0100
@@ -238,17 +238,26 @@ ssh_get_authentication_socket_for_uid(ui
}
errno = 0;
- seteuid(uid); /* To ensure a race condition is not used to circumvent the stat
- above, we will temporarily drop UID to the caller */
- if (connect(sock, (struct sockaddr *)&sunaddr, sizeof sunaddr) < 0) {
+ /* To ensure a race condition is not used to circumvent the stat
+ above, we will temporarily drop UID to the caller */
+ if (seteuid(uid) == -1) {
close(sock);
- if(errno == EACCES)
- fatal("MAJOR SECURITY WARNING: uid %lu made a deliberate and malicious attempt to open an agent socket owned by another user", (unsigned long) uid);
+ error("seteuid(%lu) failed with error: %s",
+ (unsigned long) uid, strerror(errno));
return -1;
}
+ if (connect(sock, (struct sockaddr *)&sunaddr, sizeof sunaddr) < 0) {
+ close(sock);
+ sock = -1;
+ if(errno == EACCES)
+ fatal("MAJOR SECURITY WARNING: uid %lu made a deliberate and malicious attempt to open an agent socket owned by another user", (unsigned long) uid);
+ }
- seteuid(0); /* we now continue the regularly scheduled programming */
-
+ /* we now continue the regularly scheduled programming */
+ if (0 != seteuid(0)) {
+ fatal("setuid(0) failed with error: %s", strerror(errno));
+ return -1;
+ }
return sock;
}

View File

@ -1,27 +0,0 @@
diff -up pam_ssh_agent_auth-0.9.2/iterate_ssh_agent_keys.c.seteuid pam_ssh_agent_auth-0.9.2/iterate_ssh_agent_keys.c
--- pam_ssh_agent_auth-0.9.2/iterate_ssh_agent_keys.c.seteuid 2010-09-08 08:54:29.000000000 +0200
+++ pam_ssh_agent_auth-0.9.2/iterate_ssh_agent_keys.c 2010-11-22 08:38:05.000000000 +0100
@@ -131,13 +131,18 @@ ssh_get_authentication_socket_for_uid(ui
}
errno = 0;
- seteuid(uid); /* To ensure a race condition is not used to circumvent the stat
- above, we will temporarily drop UID to the caller */
+ /* To ensure a race condition is not used to circumvent the stat
+ above, we will temporarily drop UID to the caller */
+ if (seteuid(uid) == -1) {
+ close(sock);
+ error("seteuid(%lu) failed", (unsigned long) uid);
+ return -1;
+ }
if (connect(sock, (struct sockaddr *)&sunaddr, sizeof sunaddr) < 0) {
close(sock);
- if(errno == EACCES)
- fatal("MAJOR SECURITY WARNING: uid %lu made a deliberate and malicious attempt to open an agent socket owned by another user", (unsigned long) uid);
- return -1;
+ sock = -1;
+ if(errno == EACCES)
+ fatal("MAJOR SECURITY WARNING: uid %lu made a deliberate and malicious attempt to open an agent socket owned by another user", (unsigned long) uid);
}
seteuid(0); /* we now continue the regularly scheduled programming */