This is a note to let you know that I've just added the patch titled ksmbd: fix race condition with fp to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ksmbd-fix-race-condition-with-fp.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From linkinjeon@xxxxxxxxx Mon Dec 18 16:42:27 2023 From: Namjae Jeon <linkinjeon@xxxxxxxxxx> Date: Tue, 19 Dec 2023 00:34:32 +0900 Subject: ksmbd: fix race condition with fp To: gregkh@xxxxxxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx Cc: smfrench@xxxxxxxxx, Namjae Jeon <linkinjeon@xxxxxxxxxx>, luosili <rootlab@xxxxxxxxxx>, Steve French <stfrench@xxxxxxxxxxxxx> Message-ID: <20231218153454.8090-133-linkinjeon@xxxxxxxxxx> From: Namjae Jeon <linkinjeon@xxxxxxxxxx> [ Upstream commit 5a7ee91d1154f35418367a6eaae74046fd06ed89 ] fp can used in each command. If smb2_close command is coming at the same time, UAF issue can happen by race condition. Time + Thread A | Thread B1 B2 .... B5 smb2_open | smb2_close | __open_id | insert fp to file_table | | | atomic_dec_and_test(&fp->refcount) | if fp->refcount == 0, free fp by kfree. // UAF! | use fp | + This patch add f_state not to use freed fp is used and not to free fp in use. Reported-by: luosili <rootlab@xxxxxxxxxx> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ksmbd/smb2pdu.c | 4 +++- fs/ksmbd/vfs_cache.c | 23 ++++++++++++++++++++--- fs/ksmbd/vfs_cache.h | 9 +++++++++ 3 files changed, 32 insertions(+), 4 deletions(-) --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -3367,8 +3367,10 @@ err_out: } ksmbd_revert_fsids(work); err_out1: - if (!rc) + if (!rc) { + ksmbd_update_fstate(&work->sess->file_table, fp, FP_INITED); rc = ksmbd_iov_pin_rsp(work, (void *)rsp, iov_len); + } if (rc) { if (rc == -EINVAL) rsp->hdr.Status = STATUS_INVALID_PARAMETER; --- a/fs/ksmbd/vfs_cache.c +++ b/fs/ksmbd/vfs_cache.c @@ -332,6 +332,9 @@ static void __ksmbd_close_fd(struct ksmb static struct ksmbd_file *ksmbd_fp_get(struct ksmbd_file *fp) { + if (fp->f_state != FP_INITED) + return NULL; + if (!atomic_inc_not_zero(&fp->refcount)) return NULL; return fp; @@ -381,15 +384,20 @@ int ksmbd_close_fd(struct ksmbd_work *wo return 0; ft = &work->sess->file_table; - read_lock(&ft->lock); + write_lock(&ft->lock); fp = idr_find(ft->idr, id); if (fp) { set_close_state_blocked_works(fp); - if (!atomic_dec_and_test(&fp->refcount)) + if (fp->f_state != FP_INITED) fp = NULL; + else { + fp->f_state = FP_CLOSED; + if (!atomic_dec_and_test(&fp->refcount)) + fp = NULL; + } } - read_unlock(&ft->lock); + write_unlock(&ft->lock); if (!fp) return -EINVAL; @@ -569,6 +577,7 @@ struct ksmbd_file *ksmbd_open_fd(struct fp->tcon = work->tcon; fp->volatile_id = KSMBD_NO_FID; fp->persistent_id = KSMBD_NO_FID; + fp->f_state = FP_NEW; fp->f_ci = ksmbd_inode_get(fp); if (!fp->f_ci) { @@ -590,6 +599,14 @@ err_out: return ERR_PTR(ret); } +void ksmbd_update_fstate(struct ksmbd_file_table *ft, struct ksmbd_file *fp, + unsigned int state) +{ + write_lock(&ft->lock); + fp->f_state = state; + write_unlock(&ft->lock); +} + static int __close_file_table_ids(struct ksmbd_file_table *ft, struct ksmbd_tree_connect *tcon, --- a/fs/ksmbd/vfs_cache.h +++ b/fs/ksmbd/vfs_cache.h @@ -60,6 +60,12 @@ struct ksmbd_inode { __le32 m_fattr; }; +enum { + FP_NEW = 0, + FP_INITED, + FP_CLOSED +}; + struct ksmbd_file { struct file *filp; u64 persistent_id; @@ -98,6 +104,7 @@ struct ksmbd_file { /* if ls is happening on directory, below is valid*/ struct ksmbd_readdir_data readdir_data; int dot_dotdot[2]; + unsigned int f_state; }; static inline void set_ctx_actor(struct dir_context *ctx, @@ -142,6 +149,8 @@ int ksmbd_close_inode_fds(struct ksmbd_w int ksmbd_init_global_file_table(void); void ksmbd_free_global_file_table(void); void ksmbd_set_fd_limit(unsigned long limit); +void ksmbd_update_fstate(struct ksmbd_file_table *ft, struct ksmbd_file *fp, + unsigned int state); /* * INODE hash Patches currently in stable-queue which might be from linkinjeon@xxxxxxxxx are queue-5.15/ksmbd-fix-uaf-issue-from-opinfo-conn.patch queue-5.15/ksmbd-fix-race-condition-from-parallel-smb2-lock-requests.patch queue-5.15/ksmbd-validate-session-id-and-tree-id-in-compound-request.patch queue-5.15/ksmbd-reorganize-ksmbd_iov_pin_rsp.patch queue-5.15/ksmbd-convert-to-use-sysfs_emit-sysfs_emit_at-apis.patch queue-5.15/ksmbd-validate-length-in-smb2_write.patch queue-5.15/ksmbd-add-support-for-key-exchange.patch queue-5.15/ksmbd-request-update-to-stale-share-config.patch queue-5.15/ksmbd-remove-generic_fillattr-use-in-smb2_open.patch queue-5.15/ksmbd-fix-uninitialized-pointer-read-in-smb2_create_link.patch queue-5.15/ksmbd-set-smb2_session_flag_encrypt_data-when-enforcing-data-encryption-for-this-share.patch queue-5.15/ksmbd-constify-struct-path.patch queue-5.15/ksmbd-casefold-utf-8-share-names-and-fix-ascii-lowercase-conversion.patch queue-5.15/ksmbd-validate-smb-request-protocol-id.patch queue-5.15/ksmbd-avoid-out-of-bounds-access-in-decode_preauth_ctxt.patch queue-5.15/ksmbd-release-interim-response-after-sending-status-pending-response.patch queue-5.15/ksmbd-fix-racy-issue-under-cocurrent-smb2-tree-disconnect.patch queue-5.15/ksmbd-fix-out-of-bounds-read-in-smb2_sess_setup.patch queue-5.15/ksmbd-decrease-the-number-of-smb3-smbdirect-server-sges.patch queue-5.15/ksmbd-make-utf-8-file-name-comparison-work-in-__caseless_lookup.patch queue-5.15/ksmbd-use-f_setlk-when-unlocking-a-file.patch queue-5.15/fs-introduce-lock_rename_child-helper.patch queue-5.15/ksmbd-use-kzalloc-instead-of-__gfp_zero.patch queue-5.15/ksmbd-set-ntlmssp_negotiate_seal-flag-to-challenge-blob.patch queue-5.15/ksmbd-call-ib_drain_qp-when-disconnected.patch queue-5.15/ksmbd-fix-posix_acls-and-acls-dereferencing-possible-err_ptr.patch queue-5.15/ksmbd-destroy-expired-sessions.patch queue-5.15/ksmbd-fix-resource-leak-in-smb2_lock.patch queue-5.15/ksmbd-check-iov-vector-index-in-ksmbd_conn_write.patch queue-5.15/ksmbd-hide-socket-error-message-when-ipv6-config-is-disable.patch queue-5.15/ksmbd-use-netif_is_bridge_port.patch queue-5.15/ksmbd-smbd-simplify-tracking-pending-packets.patch queue-5.15/ksmbd-implements-sess-rpc_handle_list-as-xarray.patch queue-5.15/ksmbd-remove-duplicate-flag-set-in-smb2_write.patch queue-5.15/ksmbd-separately-allocate-ci-per-dentry.patch queue-5.15/ksmbd-fix-racy-issue-from-session-setup-and-logoff.patch queue-5.15/ksmbd-fix-race-condition-between-session-lookup-and-expire.patch queue-5.15/ksmbd-fix-wrong-smbd-max-read-write-size-check.patch queue-5.15/ksmbd-replace-usage-of-found-with-dedicated-list-iterator-variable.patch queue-5.15/ksmbd-add-support-for-surrogate-pair-conversion.patch queue-5.15/ksmbd-reduce-server-smbdirect-max-send-receive-segment-sizes.patch queue-5.15/ksmbd-fix-force-create-mode-and-force-directory-mode.patch queue-5.15/ksmbd-remove-unneeded-mark_inode_dirty-in-set_info_sec.patch queue-5.15/ksmbd-fix-potential-double-free-on-smb2_read_pipe-error-path.patch queue-5.15/ksmbd-remove-unused-ksmbd_tree_conn_share-function.patch queue-5.15/ksmbd-block-asynchronous-requests-when-making-a-delay-on-session-setup.patch queue-5.15/ksmbd-call-putname-after-using-the-last-component.patch queue-5.15/ksmbd-don-t-open-code-file_path.patch queue-5.15/ksmbd-fix-passing-freed-memory-aux_payload_buf.patch queue-5.15/ksmbd-fill-sids-in-smb_find_file_posix_info-response.patch queue-5.15/ksmbd-don-t-open-code-pd.patch queue-5.15/ksmbd-shorten-experimental-warning-on-loading-the-module.patch queue-5.15/ksmbd-remove-filename-in-ksmbd_file.patch queue-5.15/ksmbd-move-oplock-handling-after-unlock-parent-dir.patch queue-5.15/ksmbd-fix-race-condition-between-tree-conn-lookup-and-disconnect.patch queue-5.15/ksmbd-smbd-introduce-read-write-credits-for-rdma-read-write.patch queue-5.15/ksmbd-fix-slab-out-of-bounds-in-init_smb2_rsp_hdr.patch queue-5.15/ksmbd-fix-recursive-locking-in-vfs-helpers.patch queue-5.15/ksmbd-fix-some-kernel-doc-comments.patch queue-5.15/ksmbd-use-struct_size-helper-in-ksmbd_negotiate_smb_dialect.patch queue-5.15/ksmbd-smbd-relax-the-count-of-sges-required.patch queue-5.15/ksmbd-fix-wrong-error-response-status-by-using-set_smb2_rsp_status.patch queue-5.15/ksmbd-fix-spelling-mistake-excceed-exceeded.patch queue-5.15/ksmbd-fix-null-pointer-dereferences-in-ksmbd_update_fstate.patch queue-5.15/ksmbd-fix-encryption-failure-issue-for-session-logoff-response.patch queue-5.15/ksmbd-prevent-memory-leak-on-error-return.patch queue-5.15/ksmbd-fix-racy-issue-from-using-d_parent-and-d_name.patch queue-5.15/ksmbd-change-security-id-to-the-one-samba-used-for-posix-extension.patch queue-5.15/ksmbd-handle-malformed-smb1-message.patch queue-5.15/ksmbd-don-t-update-op_state-as-oplock_state_none-on-error.patch queue-5.15/ksmbd-smbd-fix-connection-dropped-issue.patch queue-5.15/ksmbd-fix-racy-issue-from-smb2-close-and-logoff-with-multichannel.patch queue-5.15/ksmbd-change-the-return-value-of-ksmbd_vfs_query_maximal_access-to-void.patch queue-5.15/ksmbd-fix-slub-overflow-in-ksmbd_decode_ntlmssp_auth_blob.patch queue-5.15/ksmbd-replace-one-element-array-with-flexible-array-member.patch queue-5.15/ksmbd-fix-uninitialized-pointer-read-in-ksmbd_vfs_rename.patch queue-5.15/ksmbd-replace-one-element-arrays-with-flexible-array-members.patch queue-5.15/ksmbd-fix-unsigned-expression-compared-with-zero.patch queue-5.15/ksmbd-implements-sess-ksmbd_chann_list-as-xarray.patch queue-5.15/ksmbd-set-file-permission-mode-to-match-samba-server-posix-extension-behavior.patch queue-5.15/ksmbd-fix-wrong-interim-response-on-compound.patch queue-5.15/ksmbd-return-invalid-parameter-error-response-if-smb2-request-is-invalid.patch queue-5.15/ksmbd-smbd-validate-buffer-descriptor-structures.patch queue-5.15/ksmbd-fix-missing-rdma-capable-flag-for-ipoib-device-in-ksmbd_rdma_capable_netdev.patch queue-5.15/ksmbd-send-proper-error-response-in-smb2_tree_connect.patch queue-5.15/ksmbd-set-negotiatecontextcount-once-instead-of-every-inc.patch queue-5.15/ksmbd-fix-typo-syncronous-synchronous.patch queue-5.15/ksmbd-validate-share-name-from-share-config-response.patch queue-5.15/ksmbd-fix-possible-deadlock-in-smb2_open.patch queue-5.15/ksmbd-fix-multiple-out-of-bounds-read-during-context-decoding.patch queue-5.15/ksmbd-add-missing-calling-smb2_set_err_rsp-on-error.patch queue-5.15/ksmbd-remove-unused-ksmbd_share_configs_cleanup-function.patch queue-5.15/ksmbd-fix-out-of-bound-read-in-parse_lease_state.patch queue-5.15/ksmbd-remove-duplicated-codes.patch queue-5.15/ksmbd-remove-a-redundant-zeroing-of-memory.patch queue-5.15/ksmbd-change-leasekey-data-type-to-u8-array.patch queue-5.15/ksmbd-add-support-for-read-compound.patch queue-5.15/ksmbd-fix-kernel-doc-comment-of-ksmbd_vfs_setxattr.patch queue-5.15/ksmbd-remove-unused-compression-negotiate-ctx-packing.patch queue-5.15/ksmbd-switch-to-use-kmemdup_nul-helper.patch queue-5.15/ksmbd-fix-race-condition-from-parallel-smb2-logoff-requests.patch queue-5.15/ksmbd-fix-out-of-bound-read-in-deassemble_neg_contexts.patch queue-5.15/ksmbd-remove-unnecessary-generic_fillattr-in-smb2_open.patch queue-5.15/ksmbd-avoid-duplicate-negotiate-ctx-offset-increments.patch queue-5.15/ksmbd-remove-experimental-warning.patch queue-5.15/ksmbd-return-a-literal-instead-of-err-in-ksmbd_vfs_kern_path_locked.patch queue-5.15/ksmbd-smbd-change-prototypes-of-rdma-read-write-related-functions.patch queue-5.15/ksmbd-fix-out-of-bounds-in-init_smb2_rsp_hdr.patch queue-5.15/ksmbd-fix-possible-memory-leak-in-smb2_lock.patch queue-5.15/ksmbd-remove-unused-field-in-ksmbd_user-struct.patch queue-5.15/ksmbd-fix-one-kernel-doc-comment.patch queue-5.15/ksmbd-no-need-to-wait-for-binded-connection-termination-at-logoff.patch queue-5.15/ksmbd-fix-race-condition-with-fp.patch queue-5.15/ksmbd-fix-wrong-signingkey-creation-when-encryption-is-aes256.patch queue-5.15/ksmbd-update-kconfig-to-note-kerberos-support-and-fix-indentation.patch queue-5.15/ksmbd-move-setting-smb2_flags_async_command-and-asyncid.patch queue-5.15/smb3-fix-ksmbd-bigendian-bug-in-oplock-break-and-move-its-struct-to-smbfs_common.patch queue-5.15/ksmbd-store-fids-as-opaque-u64-integers.patch queue-5.15/ksmbd-delete-asynchronous-work-from-list.patch queue-5.15/ksmbd-use-kvzalloc-instead-of-kvmalloc.patch queue-5.15/ksmbd-smbd-change-the-return-value-of-get_sg_list.patch queue-5.15/ksmbd-add-missing-compound-request-handing-in-some-commands.patch queue-5.15/ksmbd-remove-unused-is_char_allowed-function.patch queue-5.15/ksmbd-use-oid-registry-functions-to-decode-oids.patch queue-5.15/ksmbd-fix-kernel-doc-comment-of-ksmbd_vfs_kern_path_locked.patch queue-5.15/ksmbd-use-wait_event-instead-of-schedule_timeout.patch queue-5.15/ksmbd-check-if-a-mount-point-is-crossed-during-path-lookup.patch queue-5.15/ksmbd-replace-the-ternary-conditional-operator-with-min.patch