| Message ID | 20220820004547.2135627-1-jeffxu@google.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | selftests/landlock: skip overlayfs test when kernel not support it | expand |
On 20/08/2022 02:45, jeffxu@google.com wrote: > From: Jeff Xu <jeffxu@google.com> > > Overlayfs can be disabled in kernel config, causing related tests to fail. > Add check for overlayfs’s supportability at runtime, so we can call SKIP() > when needed. > > Signed-off-by: Jeff Xu <jeffxu@chromium.org> > --- > tools/testing/selftests/landlock/fs_test.c | 56 ++++++++++++++++++++-- > 1 file changed, 53 insertions(+), 3 deletions(-) > > diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c > index 21a2ce8fa739..f604165dbd21 100644 > --- a/tools/testing/selftests/landlock/fs_test.c > +++ b/tools/testing/selftests/landlock/fs_test.c > @@ -11,6 +11,7 @@ > #include <fcntl.h> > #include <linux/landlock.h> > #include <sched.h> > +#include <stdio.h> > #include <string.h> > #include <sys/capability.h> > #include <sys/mount.h> > @@ -3398,12 +3399,53 @@ static const char (*merge_sub_files[])[] = { > * └── work > */ > > +static char *fgrep(FILE *inf, const char *str) Please move these two helpers just before prepare_layout(). I plan to use them for other filesystems. > +{ > + char line[256]; I guess we can safely set this array size to 32 for now. > + int slen = strlen(str); > + > + while (!feof(inf)) { > + if (!fgets(line, 256, inf)) Please use sizeof(line) > + break; > + if (strncmp(line, str, slen)) > + continue; > + > + return strdup(line); No need to duplicate the string, just return a boolean. > + } > + > + return NULL; > +} > + > +static bool check_overlayfs_support(void) Can be renamed to supports_overlayfs(). > +{ > + FILE *inf = fopen("/proc/filesystems", "r"); Just move the fopen() call at the end of variable declaration and add a const. > + char *res; > + bool ret = false; > + > + if (!inf) > + return false; Let's assume that a failed attempt to open /proc/filesystems means the filesystem is supported (default behavior). This can help detect such missing file (which should not happen). You can add a comment to explain the rational. > + > + res = fgrep(inf, "nodev\toverlay\n"); > + > + if (res) { > + ret = true; > + free(res); > + } > + > + fclose(inf); > + > + return ret; > +} > + > /* clang-format off */ > FIXTURE(layout2_overlay) {}; > /* clang-format on */ > > FIXTURE_SETUP(layout2_overlay) > { > + int rc; Let's stick to "ret". > + bool support; s/support/is_supported/ > + > prepare_layout(_metadata); > > create_directory(_metadata, LOWER_BASE); > @@ -3431,9 +3473,17 @@ FIXTURE_SETUP(layout2_overlay) > create_directory(_metadata, MERGE_DATA); > set_cap(_metadata, CAP_SYS_ADMIN); > set_cap(_metadata, CAP_DAC_OVERRIDE); > - ASSERT_EQ(0, mount("overlay", MERGE_DATA, "overlay", 0, > - "lowerdir=" LOWER_DATA ",upperdir=" UPPER_DATA > - ",workdir=" UPPER_WORK)); > + > + rc = mount("overlay", MERGE_DATA, "overlay", 0, > + "lowerdir=" LOWER_DATA ",upperdir=" UPPER_DATA > + ",workdir=" UPPER_WORK); Please format with clang-format-14, otherwise I'll do it myself. > + if (rc < 0) { Please check errno with ASSERT_EQ() to differentiate from a skippable mount and an unexpected error. The next TH_LOG() would then not be needed. > + TH_LOG("mount overlay failed: errorno=%s", strerror(errno)); > + support = check_overlayfs_support(); > + ASSERT_FALSE(support); ASSERT_FALSE(supports_overlayfs()); > + SKIP(return, "overlayfs is not supported"); > + } > + Please keep these clear_cap() calls just after the mount call. > clear_cap(_metadata, CAP_DAC_OVERRIDE); > clear_cap(_metadata, CAP_SYS_ADMIN); > }
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c index 21a2ce8fa739..f604165dbd21 100644 --- a/tools/testing/selftests/landlock/fs_test.c +++ b/tools/testing/selftests/landlock/fs_test.c @@ -11,6 +11,7 @@ #include <fcntl.h> #include <linux/landlock.h> #include <sched.h> +#include <stdio.h> #include <string.h> #include <sys/capability.h> #include <sys/mount.h> @@ -3398,12 +3399,53 @@ static const char (*merge_sub_files[])[] = { * └── work */ +static char *fgrep(FILE *inf, const char *str) +{ + char line[256]; + int slen = strlen(str); + + while (!feof(inf)) { + if (!fgets(line, 256, inf)) + break; + if (strncmp(line, str, slen)) + continue; + + return strdup(line); + } + + return NULL; +} + +static bool check_overlayfs_support(void) +{ + FILE *inf = fopen("/proc/filesystems", "r"); + char *res; + bool ret = false; + + if (!inf) + return false; + + res = fgrep(inf, "nodev\toverlay\n"); + + if (res) { + ret = true; + free(res); + } + + fclose(inf); + + return ret; +} + /* clang-format off */ FIXTURE(layout2_overlay) {}; /* clang-format on */ FIXTURE_SETUP(layout2_overlay) { + int rc; + bool support; + prepare_layout(_metadata); create_directory(_metadata, LOWER_BASE); @@ -3431,9 +3473,17 @@ FIXTURE_SETUP(layout2_overlay) create_directory(_metadata, MERGE_DATA); set_cap(_metadata, CAP_SYS_ADMIN); set_cap(_metadata, CAP_DAC_OVERRIDE); - ASSERT_EQ(0, mount("overlay", MERGE_DATA, "overlay", 0, - "lowerdir=" LOWER_DATA ",upperdir=" UPPER_DATA - ",workdir=" UPPER_WORK)); + + rc = mount("overlay", MERGE_DATA, "overlay", 0, + "lowerdir=" LOWER_DATA ",upperdir=" UPPER_DATA + ",workdir=" UPPER_WORK); + if (rc < 0) { + TH_LOG("mount overlay failed: errorno=%s", strerror(errno)); + support = check_overlayfs_support(); + ASSERT_FALSE(support); + SKIP(return, "overlayfs is not supported"); + } + clear_cap(_metadata, CAP_DAC_OVERRIDE); clear_cap(_metadata, CAP_SYS_ADMIN); }