pam: fix CVE-2024-22365 pam_namespace misses

Upstream-Status: Backport from https://github.com/linux-pam/linux-pam/commit/031bb5a5d0d950253b68138b498dc93be69a64cb

(From OE-Core rev: 9af2e012ee4483541559788dfb9510e0223daefe)

Signed-off-by: Hitendra Prajapati <hprajapati@mvista.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

2 files changed, 63 insertions, 0 deletions

diff --git a/meta/recipes-extended/pam/libpam/CVE-2024-22365.patch b/meta/recipes-extended/pam/libpam/CVE-2024-22365.patch
new file mode 100644
index 0000000000..e9e3a078e0
--- /dev/null
+++ b/meta/recipes-extended/pam/libpam/CVE-2024-22365.patch
@@ -0,0 +1,62 @@
+From 031bb5a5d0d950253b68138b498dc93be69a64cb Mon Sep 17 00:00:00 2001
+From: Matthias Gerstner <matthias.gerstner@suse.de>
+Date: Wed, 27 Dec 2023 14:01:59 +0100
+Subject: [PATCH] pam_namespace: protect_dir(): use O_DIRECTORY to prevent
+ local DoS situations
+
+Without O_DIRECTORY the path crawling logic is subject to e.g. FIFOs
+being placed in user controlled directories, causing the PAM module to
+block indefinitely during `openat()`.
+
+Pass O_DIRECTORY to cause the `openat()` to fail if the path does not
+refer to a directory.
+
+With this the check whether the final path element is a directory
+becomes unnecessary, drop it.
+
+Upstream-Status: Backport [https://github.com/linux-pam/linux-pam/commit/031bb5a5d0d950253b68138b498dc93be69a64cb]
+CVE: CVE-2024-22365
+Signed-off-by: Hitendra Prajapati <hprajapati@mvista.com>
+---
+ modules/pam_namespace/pam_namespace.c      | 18 +-----------------
+ 1 file changed, 1 insertion(+), 17 deletions(-)
+
+diff --git a/modules/pam_namespace/pam_namespace.c b/modules/pam_namespace/pam_namespace.c
+index 4d4188d..d6b1d3c 100644
+--- a/modules/pam_namespace/pam_namespace.c
++++ b/modules/pam_namespace/pam_namespace.c
+@@ -1103,7 +1103,7 @@ static int protect_dir(const char *path, mode_t mode, int do_mkdir,
+        int dfd = AT_FDCWD;
+        int dfd_next;
+        int save_errno;
+-       int flags = O_RDONLY;
++       int flags = O_RDONLY | O_DIRECTORY;
+        int rv = -1;
+        struct stat st;
+ 
+@@ -1157,22 +1157,6 @@ static int protect_dir(const char *path, mode_t mode, int do_mkdir,
+                rv = openat(dfd, dir, flags);
+        }
+ 
+-       if (rv != -1) {
+-               if (fstat(rv, &st) != 0) {
+-                       save_errno = errno;
+-                       close(rv);
+-                       rv = -1;
+-                       errno = save_errno;
+-                       goto error;
+-               }
+-               if (!S_ISDIR(st.st_mode)) {
+-                       close(rv);
+-                       errno = ENOTDIR;
+-                       rv = -1;
+-                       goto error;
+-               }
+-       }
+-
+        if (flags & O_NOFOLLOW) {
+                /* we are inside user-owned dir - protect */
+                if (protect_mount(rv, p, idata) == -1) {
+-- 
+2.25.1
+
diff --git a/meta/recipes-extended/pam/libpam_1.5.2.bb b/meta/recipes-extended/pam/libpam_1.5.2.bb
index 0799102f8e..20745aa837 100644
--- a/meta/recipes-extended/pam/libpam_1.5.2.bb
+++ b/meta/recipes-extended/pam/libpam_1.5.2.bb
@@ -26,6 +26,7 @@ SRC_URI = "https://github.com/linux-pam/linux-pam/releases/download/v${PV}/Linux
            file://pam-volatiles.conf \
            file://CVE-2022-28321-0002.patch \
            file://0001-pam_motd-do-not-rely-on-all-filesystems-providing-a-.patch \
+           file://CVE-2024-22365.patch \
            "
 
 SRC_URI[sha256sum] = "e4ec7131a91da44512574268f493c6d8ca105c87091691b8e9b56ca685d4f94d"