From 3c87ef2961dedb10d1f674c6a530e00dbab8ec1b Mon Sep 17 00:00:00 2001 From: Jan Stancek Date: Tue, 17 Jul 2018 10:26:39 +0200 Subject: [PATCH] open|creat: skip S_ISGID check on files created by non-group members 0fa3ecd87848 ("Fix up non-directory creation in SGID directories") fixes problem described in CVE-2018-13405. This commit is getting backported to older streams as well. This patch removes S_ISGID check for files created by non-group members in LTP tests creat08 and open10. Once 0fa3ecd87848 will be in non-rc kernel, we could add a new test for this CVE that would be limited to 4.18+ kernels. Signed-off-by: Jan Stancek Acked-by: Cyril Hrubis Reviewed-by: Naresh Kamboju Upstream-Status: Backport [ git://github.com/linux-test-project/ltp.git 3c87ef2961dedb10d1f674c6a530e00dbab8ec1b "open|creat: skip S_ISGID check on files created by non-group members" ] Signed-off-by: He Zhe --- testcases/kernel/syscalls/creat/creat08.c | 13 ++++++------- testcases/kernel/syscalls/open/open10.c | 12 +++++------- 2 files changed, 11 insertions(+), 14 deletions(-) diff --git a/testcases/kernel/syscalls/creat/creat08.c b/testcases/kernel/syscalls/creat/creat08.c index 50f2b3993..d22558ac3 100644 --- a/testcases/kernel/syscalls/creat/creat08.c +++ b/testcases/kernel/syscalls/creat/creat08.c @@ -361,13 +361,12 @@ int main(int ac, char **av) local_flag = FAILED; } - /* Verify modes */ - if (!(buf.st_mode & S_ISGID)) { - tst_resm(TFAIL, - "%s: Incorrect modes, setgid bit should be set", - setgid_B); - local_flag = FAILED; - } + /* + * Skip S_ISGID check + * 0fa3ecd87848 ("Fix up non-directory creation in SGID directories") + * clears S_ISGID for files created by non-group members + */ + close(fd); if (local_flag == PASSED) { diff --git a/testcases/kernel/syscalls/open/open10.c b/testcases/kernel/syscalls/open/open10.c index 613f2288f..14feec9e1 100644 --- a/testcases/kernel/syscalls/open/open10.c +++ b/testcases/kernel/syscalls/open/open10.c @@ -345,13 +345,11 @@ int main(int ac, char *av[]) local_flag = FAILED; } - /* Verify modes */ - if (!(buf.st_mode & S_ISGID)) { - tst_resm(TFAIL, - "%s: Incorrect modes, setgid bit not set", - setgid_B); - local_flag = FAILED; - } + /* + * Skip S_ISGID check + * 0fa3ecd87848 ("Fix up non-directory creation in SGID directories") + * clears S_ISGID for files created by non-group members + */ if (local_flag == PASSED) { tst_resm(TPASS, "Test passed in block2."); -- 2.11.0