From 31f75bfecd9cef7d485b1cda3c6c38cc0b4a5c6c Mon Sep 17 00:00:00 2001 From: John Johansen Date: Mon, 16 Jan 2017 00:43:07 -0800 Subject: [PATCH] apparmor: make computing policy hashes conditional on kernel parameter Allow turning off the computation of the policy hashes via the apparmor.hash_policy kernel parameter. Signed-off-by: John Johansen --- security/apparmor/lsm.c | 46 +++++++++++++++++++-------------------- security/apparmor/policy_unpack.c | 15 ++++++++----- 2 files changed, 32 insertions(+), 29 deletions(-) diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 264aa19..6a5cf54 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -166,42 +166,42 @@ static int common_perm(const char *op, const struct path *path, u32 mask, } /** - * common_perm_dir_dentry - common permission wrapper when path is dir, dentry + * common_perm_cond - common permission wrapper around inode cond * @op: operation being checked - * @dir: directory of the dentry (NOT NULL) - * @dentry: dentry to check (NOT NULL) + * @path: location to check (NOT NULL) * @mask: requested permissions mask - * @cond: conditional info for the permission request (NOT NULL) * * Returns: %0 else error code if error or permission denied */ -static int common_perm_dir_dentry(const char *op, const struct path *dir, - struct dentry *dentry, u32 mask, - struct path_cond *cond) +static int common_perm_cond(const char *op, const struct path *path, u32 mask) { - struct path path = { .mnt = dir->mnt, .dentry = dentry }; + struct path_cond cond = { d_backing_inode(path->dentry)->i_uid, + d_backing_inode(path->dentry)->i_mode + }; - return common_perm(op, &path, mask, cond); + if (!path_mediated_fs(path->dentry)) + return 0; + + return common_perm(op, path, mask, &cond); } /** - * common_perm_path - common permission wrapper when mnt, dentry + * common_perm_dir_dentry - common permission wrapper when path is dir, dentry * @op: operation being checked - * @path: location to check (NOT NULL) + * @dir: directory of the dentry (NOT NULL) + * @dentry: dentry to check (NOT NULL) * @mask: requested permissions mask + * @cond: conditional info for the permission request (NOT NULL) * * Returns: %0 else error code if error or permission denied */ -static inline int common_perm_path(const char *op, const struct path *path, - u32 mask) +static int common_perm_dir_dentry(const char *op, const struct path *dir, + struct dentry *dentry, u32 mask, + struct path_cond *cond) { - struct path_cond cond = { d_backing_inode(path->dentry)->i_uid, - d_backing_inode(path->dentry)->i_mode - }; - if (!path_mediated_fs(path->dentry)) - return 0; + struct path path = { .mnt = dir->mnt, .dentry = dentry }; - return common_perm(op, path, mask, &cond); + return common_perm(op, &path, mask, cond); } /** @@ -274,7 +274,7 @@ static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry, static int apparmor_path_truncate(const struct path *path) { - return common_perm_path(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE); + return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE); } static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry, @@ -333,17 +333,17 @@ static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_d static int apparmor_path_chmod(const struct path *path, umode_t mode) { - return common_perm_path(OP_CHMOD, path, AA_MAY_CHMOD); + return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD); } static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid) { - return common_perm_path(OP_CHOWN, path, AA_MAY_CHOWN); + return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN); } static int apparmor_inode_getattr(const struct path *path) { - return common_perm_path(OP_GETATTR, path, AA_MAY_META_READ); + return common_perm_cond(OP_GETATTR, path, AA_MAY_META_READ); } static int apparmor_file_open(struct file *file, const struct cred *cred) diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 441efc9..59c891a 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -825,7 +825,8 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, if (error) goto fail_profile; - error = aa_calc_profile_hash(profile, e.version, start, + if (aa_g_hash_policy) + error = aa_calc_profile_hash(profile, e.version, start, e.pos - start); if (error) goto fail_profile; @@ -841,11 +842,13 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, list_add_tail(&ent->list, lh); } udata->abi = e.version & K_ABI_MASK; - udata->hash = aa_calc_hash(udata->data, udata->size); - if (IS_ERR(udata->hash)) { - error = PTR_ERR(udata->hash); - udata->hash = NULL; - goto fail; + if (aa_g_hash_policy) { + udata->hash = aa_calc_hash(udata->data, udata->size); + if (IS_ERR(udata->hash)) { + error = PTR_ERR(udata->hash); + udata->hash = NULL; + goto fail; + } } return 0; -- 2.7.4