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author | Eric W. Biederman <ebiederm@xmission.com> | 2014-12-02 19:56:30 (GMT) |
---|---|---|
committer | Eric W. Biederman <ebiederm@xmission.com> | 2014-12-12 00:07:07 (GMT) |
commit | db86da7cb76f797a1a8b445166a15cb922c6ff85 (patch) | |
tree | 555f131be82199d97ed63118d8f00d3a768f5f96 | |
parent | 36476beac4f8ca9dc7722790b2e8ef0e8e51034e (diff) | |
download | linux-db86da7cb76f797a1a8b445166a15cb922c6ff85.tar.xz |
userns: Unbreak the unprivileged remount tests
A security fix in caused the way the unprivileged remount tests were
using user namespaces to break. Tweak the way user namespaces are
being used so the test works again.
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
-rw-r--r-- | tools/testing/selftests/mount/unprivileged-remount-test.c | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/tools/testing/selftests/mount/unprivileged-remount-test.c b/tools/testing/selftests/mount/unprivileged-remount-test.c index 9669d37..5177850 100644 --- a/tools/testing/selftests/mount/unprivileged-remount-test.c +++ b/tools/testing/selftests/mount/unprivileged-remount-test.c @@ -53,17 +53,14 @@ static void die(char *fmt, ...) exit(EXIT_FAILURE); } -static void write_file(char *filename, char *fmt, ...) +static void vmaybe_write_file(bool enoent_ok, char *filename, char *fmt, va_list ap) { char buf[4096]; int fd; ssize_t written; int buf_len; - va_list ap; - va_start(ap, fmt); buf_len = vsnprintf(buf, sizeof(buf), fmt, ap); - va_end(ap); if (buf_len < 0) { die("vsnprintf failed: %s\n", strerror(errno)); @@ -74,6 +71,8 @@ static void write_file(char *filename, char *fmt, ...) fd = open(filename, O_WRONLY); if (fd < 0) { + if ((errno == ENOENT) && enoent_ok) + return; die("open of %s failed: %s\n", filename, strerror(errno)); } @@ -92,6 +91,26 @@ static void write_file(char *filename, char *fmt, ...) } } +static void maybe_write_file(char *filename, char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + vmaybe_write_file(true, filename, fmt, ap); + va_end(ap); + +} + +static void write_file(char *filename, char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + vmaybe_write_file(false, filename, fmt, ap); + va_end(ap); + +} + static int read_mnt_flags(const char *path) { int ret; @@ -144,13 +163,10 @@ static void create_and_enter_userns(void) strerror(errno)); } + maybe_write_file("/proc/self/setgroups", "deny"); write_file("/proc/self/uid_map", "0 %d 1", uid); write_file("/proc/self/gid_map", "0 %d 1", gid); - if (setgroups(0, NULL) != 0) { - die("setgroups failed: %s\n", - strerror(errno)); - } if (setgid(0) != 0) { die ("setgid(0) failed %s\n", strerror(errno)); |