diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 701cb3e5ec3b..62301ddbbe5e 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -310,6 +310,7 @@ static struct dentry *aafs_create_dir(const char *name, struct dentry *parent) * @name: name of dentry to create * @parent: parent directory for this dentry * @target: if symlink, symlink target string + * @private: private data * @iops: struct of inode_operations that should be used * * If @target parameter is %NULL, then the @iops parameter needs to be @@ -318,17 +319,17 @@ static struct dentry *aafs_create_dir(const char *name, struct dentry *parent) static struct dentry *aafs_create_symlink(const char *name, struct dentry *parent, const char *target, + void *private, const struct inode_operations *iops) { struct dentry *dent; char *link = NULL; if (target) { - link = kstrdup(target, GFP_KERNEL); if (!link) return ERR_PTR(-ENOMEM); } - dent = aafs_create(name, S_IFLNK | 0444, parent, NULL, link, NULL, + dent = aafs_create(name, S_IFLNK | 0444, parent, private, link, NULL, iops); if (IS_ERR(dent)) kfree(link); @@ -1479,26 +1480,95 @@ static int profile_depth(struct aa_profile *profile) return depth; } -static int gen_symlink_name(char *buffer, size_t bsize, int depth, - const char *dirname, const char *fname) +static char *gen_symlink_name(int depth, const char *dirname, const char *fname) { + char *buffer, *s; int error; + int size = depth * 6 + strlen(dirname) + strlen(fname) + 11; + + s = buffer = kmalloc(size, GFP_KERNEL); + if (!buffer) + return ERR_PTR(-ENOMEM); for (; depth > 0; depth--) { - if (bsize < 7) - return -ENAMETOOLONG; - strcpy(buffer, "../../"); - buffer += 6; - bsize -= 6; + strcpy(s, "../../"); + s += 6; + size -= 6; } - error = snprintf(buffer, bsize, "raw_data/%s/%s", dirname, fname); - if (error >= bsize || error < 0) - return -ENAMETOOLONG; + error = snprintf(s, size, "raw_data/%s/%s", dirname, fname); + if (error >= size || error < 0) + return ERR_PTR(-ENAMETOOLONG); - return 0; + return buffer; } +static void rawdata_link_cb(void *arg) +{ + kfree(arg); +} + +static const char *rawdata_get_link_base(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done, + const char *name) +{ + struct aa_proxy *proxy = inode->i_private; + struct aa_label *label; + struct aa_profile *profile; + char *target; + int depth; + + if (!dentry) + return ERR_PTR(-ECHILD); + + label = aa_get_label_rcu(&proxy->label); + profile = labels_profile(label); + depth = profile_depth(profile); + target = gen_symlink_name(depth, profile->rawdata->name, name); + aa_put_label(label); + + if (IS_ERR(target)) + return target; + + set_delayed_call(done, rawdata_link_cb, target); + + return target; +} + +static const char *rawdata_get_link_sha1(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "sha1"); +} + +static const char *rawdata_get_link_abi(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "abi"); +} + +static const char *rawdata_get_link_data(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "raw_data"); +} + +static const struct inode_operations rawdata_link_sha1_iops = { + .get_link = rawdata_get_link_sha1, +}; + +static const struct inode_operations rawdata_link_abi_iops = { + .get_link = rawdata_get_link_abi, +}; +static const struct inode_operations rawdata_link_data_iops = { + .get_link = rawdata_get_link_data, +}; + + /* * Requires: @profile->ns->lock held */ @@ -1569,34 +1639,28 @@ int __aafs_profile_mkdir(struct aa_profile *profile, struct dentry *parent) } if (profile->rawdata) { - char target[64]; - int depth = profile_depth(profile); - - error = gen_symlink_name(target, sizeof(target), depth, - profile->rawdata->name, "sha1"); - if (error < 0) - goto fail2; - dent = aafs_create_symlink("raw_sha1", dir, target, NULL); + dent = aafs_create_symlink("raw_sha1", dir, NULL, + profile->label.proxy, + &rawdata_link_sha1_iops); if (IS_ERR(dent)) goto fail; + aa_get_proxy(profile->label.proxy); profile->dents[AAFS_PROF_RAW_HASH] = dent; - error = gen_symlink_name(target, sizeof(target), depth, - profile->rawdata->name, "abi"); - if (error < 0) - goto fail2; - dent = aafs_create_symlink("raw_abi", dir, target, NULL); + dent = aafs_create_symlink("raw_abi", dir, NULL, + profile->label.proxy, + &rawdata_link_abi_iops); if (IS_ERR(dent)) goto fail; + aa_get_proxy(profile->label.proxy); profile->dents[AAFS_PROF_RAW_ABI] = dent; - error = gen_symlink_name(target, sizeof(target), depth, - profile->rawdata->name, "raw_data"); - if (error < 0) - goto fail2; - dent = aafs_create_symlink("raw_data", dir, target, NULL); + dent = aafs_create_symlink("raw_data", dir, NULL, + profile->label.proxy, + &rawdata_link_data_iops); if (IS_ERR(dent)) goto fail; + aa_get_proxy(profile->label.proxy); profile->dents[AAFS_PROF_RAW_DATA] = dent; }