Merging upstream version 252.23.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 24 insertions, 1 deletions

diff --git a/src/shared/seccomp-util.c b/src/shared/seccomp-util.c
index 77cacb3..1c6bdc5 100644
--- a/src/shared/seccomp-util.c
+++ b/src/shared/seccomp-util.c
@@ -468,6 +468,7 @@ const SyscallFilterSet syscall_filter_sets[_SYSCALL_FILTER_SET_MAX] = {
                 "fchdir\0"
                 "fchmod\0"
                 "fchmodat\0"
+                "fchmodat2\0"
                 "fcntl\0"
                 "fcntl64\0"
                 "fgetxattr\0"
@@ -2031,7 +2032,7 @@ int seccomp_protect_hostname(void) {
 static int seccomp_restrict_sxid(scmp_filter_ctx seccomp, mode_t m) {
         /* Checks the mode_t parameter of the following system calls:
          *
-         *       → chmod() + fchmod() + fchmodat()
+         *       → chmod() + fchmod() + fchmodat() + fchmodat2()
          *       → open() + creat() + openat()
          *       → mkdir() + mkdirat()
          *       → mknod() + mknodat()
@@ -2074,6 +2075,28 @@ static int seccomp_restrict_sxid(scmp_filter_ctx seccomp, mode_t m) {
         else
                 any = true;
 
+#if defined(__SNR_fchmodat2)
+        r = seccomp_rule_add_exact(
+                        seccomp,
+                        SCMP_ACT_ERRNO(EPERM),
+                        SCMP_SYS(fchmodat2),
+                        1,
+                        SCMP_A2(SCMP_CMP_MASKED_EQ, m, m));
+#else
+        /* It looks like this libseccomp does not know about fchmodat2().
+         * Pretend the fchmodat2() system call is not supported at all,
+         * regardless of the kernel version. */
+        r = seccomp_rule_add_exact(
+                        seccomp,
+                        SCMP_ACT_ERRNO(ENOSYS),
+                        __NR_fchmodat2,
+                        0);
+#endif
+        if (r < 0)
+                log_debug_errno(r, "Failed to add filter for fchmodat2: %m");
+        else
+                any = true;
+
         r = seccomp_rule_add_exact(
                         seccomp,
                         SCMP_ACT_ERRNO(EPERM),