From d8db5b1ca9d4c57e49893d0f78e6d5ce81450cc8 Mon Sep 17 00:00:00 2001 From: Xiaolei Li Date: Fri, 23 Jun 2017 10:37:23 +0800 Subject: [PATCH] ubifs: Massage assert in ubifs_xattr_set() wrt. init_xattrs The inode is not locked in init_xattrs when creating a new inode. Without this patch, there will occurs assert when booting or creating a new file, if the kernel config CONFIG_SECURITY_SMACK is enabled. Log likes: UBIFS assert failed in ubifs_xattr_set at 298 (pid 1156) CPU: 1 PID: 1156 Comm: ldconfig Tainted: G S 4.12.0-rc1-207440-g1e70b02 #2 Hardware name: MediaTek MT2712 evaluation board (DT) Call trace: [] dump_backtrace+0x0/0x238 [] show_stack+0x14/0x20 [] dump_stack+0x9c/0xc0 [] ubifs_xattr_set+0x374/0x5e0 [] init_xattrs+0x5c/0xb8 [] security_inode_init_security+0x110/0x190 [] ubifs_init_security+0x30/0x68 [] ubifs_mkdir+0x100/0x200 [] vfs_mkdir+0x11c/0x1b8 [] SyS_mkdirat+0x74/0xd0 [] __sys_trace_return+0x0/0x4 Signed-off-by: Xiaolei Li Signed-off-by: Richard Weinberger --- fs/ubifs/crypto.c | 7 ++++++- fs/ubifs/ubifs.h | 2 +- fs/ubifs/xattr.c | 17 ++++++++--------- 3 files changed, 15 insertions(+), 11 deletions(-) diff --git a/fs/ubifs/crypto.c b/fs/ubifs/crypto.c index 382ed42..114ba45 100644 --- a/fs/ubifs/crypto.c +++ b/fs/ubifs/crypto.c @@ -9,8 +9,13 @@ static int ubifs_crypt_get_context(struct inode *inode, void *ctx, size_t len) static int ubifs_crypt_set_context(struct inode *inode, const void *ctx, size_t len, void *fs_data) { + /* + * Creating an encryption context is done unlocked since we + * operate on a new inode which is not visible to other users + * at this point. So, no need to check whether inode is locked. + */ return ubifs_xattr_set(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT, - ctx, len, 0); + ctx, len, 0, false); } static bool ubifs_crypt_empty_dir(struct inode *inode) diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index d933eda..cd43651 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -1755,7 +1755,7 @@ int ubifs_check_dir_empty(struct inode *dir); extern const struct xattr_handler *ubifs_xattr_handlers[]; ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size); int ubifs_xattr_set(struct inode *host, const char *name, const void *value, - size_t size, int flags); + size_t size, int flags, bool check_lock); ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf, size_t size); void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum); diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c index 98f1125..c13eae8 100644 --- a/fs/ubifs/xattr.c +++ b/fs/ubifs/xattr.c @@ -280,7 +280,7 @@ static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum) } int ubifs_xattr_set(struct inode *host, const char *name, const void *value, - size_t size, int flags) + size_t size, int flags, bool check_lock) { struct inode *inode; struct ubifs_info *c = host->i_sb->s_fs_info; @@ -289,12 +289,7 @@ int ubifs_xattr_set(struct inode *host, const char *name, const void *value, union ubifs_key key; int err; - /* - * Creating an encryption context is done unlocked since we - * operate on a new inode which is not visible to other users - * at this point. - */ - if (strcmp(name, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) != 0) + if (check_lock) ubifs_assert(inode_is_locked(host)); if (size > UBIFS_MAX_INO_DATA) @@ -598,8 +593,12 @@ static int init_xattrs(struct inode *inode, const struct xattr *xattr_array, } strcpy(name, XATTR_SECURITY_PREFIX); strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); + /* + * creating a new inode without holding the inode rwsem, + * no need to check whether inode is locked. + */ err = ubifs_xattr_set(inode, name, xattr->value, - xattr->value_len, 0); + xattr->value_len, 0, false); kfree(name); if (err < 0) break; @@ -646,7 +645,7 @@ static int xattr_set(const struct xattr_handler *handler, name = xattr_full_name(handler, name); if (value) - return ubifs_xattr_set(inode, name, value, size, flags); + return ubifs_xattr_set(inode, name, value, size, flags, true); else return ubifs_xattr_remove(inode, name); } -- 2.7.4