7.1-stable patches

added patches:
	bpf-reject-bpf_map_type_inode_storage-creation-if-bpf-lsm-is-uninitialized.patch

diff --git a/queue-7.1/bpf-reject-bpf_map_type_inode_storage-creation-if-bpf-lsm-is-uninitialized.patch b/queue-7.1/bpf-reject-bpf_map_type_inode_storage-creation-if-bpf-lsm-is-uninitialized.patch
new file mode 100644 (file)
index 0000000..1b28454
--- /dev/null
+++ b/queue-7.1/bpf-reject-bpf_map_type_inode_storage-creation-if-bpf-lsm-is-uninitialized.patch
@@ -0,0 +1,111 @@
+From a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 Mon Sep 17 00:00:00 2001
+From: Matt Bobrowski <mattbobrowski@google.com>
+Date: Sun, 28 Jun 2026 20:11:03 +0000
+Subject: bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized
+
+From: Matt Bobrowski <mattbobrowski@google.com>
+
+commit a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 upstream.
+
+When CONFIG_BPF_LSM=y is set, BPF inode storage maps
+(BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However,
+if the BPF LSM is not explicitly enabled at boot time (e.g. omitted
+from the "lsm=" boot parameter), lsm_prepare() is never executed for
+the BPF LSM.
+
+Consequently, the BPF inode security blob offset
+(bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at
+its default compiled size of 8 bytes instead of being updated to a
+valid offset past the reserved struct rcu_head (typically 16 bytes
+or more).
+
+When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE
+map, bpf_inode() evaluates inode->i_security + 8. This erroneously
+aliases the struct rcu_head.func callback pointer at the beginning
+of the inode->i_security blob. During subsequent map element cleanup
+or inode destruction, writing NULL to owner_storage clears the queued
+RCU callback pointer. When rcu_do_batch() later executes the queued
+callback, it attempts an instruction fetch at address 0x0, triggering
+an immediate kernel panic.
+
+Fix this by introducing a global bpf_lsm_initialized boolean flag
+marked with __ro_after_init. Set this flag to true inside bpf_lsm_init()
+when the LSM framework successfully registers the BPF LSM. Gate map
+allocation in inode_storage_map_alloc() on this flag, returning
+-EOPNOTSUPP if the BPF LSM is in turn uninitialized.
+
+This fail-fast approach prevents userspace from allocating inode
+storage maps when the supporting BPF LSM infrastructure is absent,
+avoiding zombie map states.
+
+Fixes: 8ea636848aca ("bpf: Implement bpf_local_storage for inodes")
+Reported-by: oxsignal <awo@kakao.com>
+Signed-off-by: Matt Bobrowski <mattbobrowski@google.com>
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
+Reviewed-by: Amery Hung <ameryhung@gmail.com>
+Link: https://lore.kernel.org/bpf/20260628201103.3624525-1-mattbobrowski@google.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/bpf_lsm.h        |    4 ++++
+ kernel/bpf/bpf_inode_storage.c |    9 +++++++++
+ security/bpf/hooks.c           |    3 +++
+ 3 files changed, 16 insertions(+)
+
+--- a/include/linux/bpf_lsm.h
++++ b/include/linux/bpf_lsm.h
+@@ -14,6 +14,8 @@
+ 
+ #ifdef CONFIG_BPF_LSM
+ 
++extern bool bpf_lsm_initialized __ro_after_init;
++
+ #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
+       RET bpf_lsm_##NAME(__VA_ARGS__);
+ #include <linux/lsm_hook_defs.h>
+@@ -55,6 +57,8 @@ bool bpf_lsm_has_d_inode_locked(const st
+ 
+ #else /* !CONFIG_BPF_LSM */
+ 
++#define bpf_lsm_initialized false
++
+ static inline bool bpf_lsm_is_sleepable_hook(u32 btf_id)
+ {
+       return false;
+--- a/kernel/bpf/bpf_inode_storage.c
++++ b/kernel/bpf/bpf_inode_storage.c
+@@ -178,6 +178,15 @@ static int notsupp_get_next_key(struct b
+ 
+ static struct bpf_map *inode_storage_map_alloc(union bpf_attr *attr)
+ {
++      /*
++       * Do not allow allocation of BPF_MAP_TYPE_INODE_STORAGE if the BPF LSM
++       * was not initialized by the LSM framework at boot. Without proper
++       * initialization, the BPF inode security blob offset remains unprepared,
++       * causing bpf_inode() to calculate an invalid memory offset and corrupt
++       * inode->i_security.
++       */
++      if (!bpf_lsm_initialized)
++              return ERR_PTR(-EOPNOTSUPP);
+       return bpf_local_storage_map_alloc(attr, &inode_cache);
+ }
+ 
+--- a/security/bpf/hooks.c
++++ b/security/bpf/hooks.c
+@@ -7,6 +7,8 @@
+ #include <linux/bpf_lsm.h>
+ #include <uapi/linux/lsm.h>
+ 
++bool bpf_lsm_initialized __ro_after_init;
++
+ static struct security_hook_list bpf_lsm_hooks[] __ro_after_init = {
+       #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
+       LSM_HOOK_INIT(NAME, bpf_lsm_##NAME),
+@@ -24,6 +26,7 @@ static int __init bpf_lsm_init(void)
+ {
+       security_add_hooks(bpf_lsm_hooks, ARRAY_SIZE(bpf_lsm_hooks),
+                          &bpf_lsmid);
++      bpf_lsm_initialized = true;
+       pr_info("LSM support for eBPF active\n");
+       return 0;
+ }

diff --git a/queue-7.1/series b/queue-7.1/series
index 6a15df52fa28631d636218c418342129a0948215..3f686228f6e5b8b17b0154861be52a5b6269733c 100644 (file)
--- a/queue-7.1/series
+++ b/queue-7.1/series
@@ -427,3 +427,4 @@ mm-do-file-ownership-checks-with-the-proper-mount-idmap.patch
 selftests-mm-pagemap_ioctl-use-the-correct-page-size-for-transact_test.patch
 selftests-mm-fix-ksft_process_madv.sh-test-category.patch
 nouveau-vmm-fix-another-spt-lpt-race.patch
+bpf-reject-bpf_map_type_inode_storage-creation-if-bpf-lsm-is-uninitialized.patch