From bce8d1120707c06088928b2ee52a58703d74ac29 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 13 Oct 2014 19:42:53 -0700 Subject: f2fs: avoid deadlock on init_inode_metadata Previously, init_inode_metadata does not hold any parent directory's inode page. So, f2fs_init_acl can grab its parent inode page without any problem. But, when we use inline_dentry, that page is grabbed during f2fs_add_link, so that we can fall into deadlock condition like below. INFO: task mknod:11006 blocked for more than 120 seconds. Tainted: G OE 3.17.0-rc1+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. mknod D ffff88003fc94580 0 11006 11004 0x00000000 ffff880007717b10 0000000000000002 ffff88003c323220 ffff880007717fd8 0000000000014580 0000000000014580 ffff88003daecb30 ffff88003c323220 ffff88003fc94e80 ffff88003ffbb4e8 ffff880007717ba0 0000000000000002 Call Trace: [] ? bit_wait+0x50/0x50 [] io_schedule+0x9d/0x130 [] bit_wait_io+0x2c/0x50 [] __wait_on_bit_lock+0x4b/0xb0 [] __lock_page+0x67/0x70 [] ? autoremove_wake_function+0x40/0x40 [] pagecache_get_page+0x14c/0x1e0 [] get_node_page+0x59/0x130 [f2fs] [] read_all_xattrs+0x24d/0x430 [f2fs] [] f2fs_getxattr+0x52/0xe0 [f2fs] [] f2fs_get_acl+0x41/0x2d0 [f2fs] [] get_acl+0x47/0x70 [] posix_acl_create+0x5a/0x150 [] f2fs_init_acl+0x29/0xcb [f2fs] [] init_inode_metadata+0x5d/0x340 [f2fs] [] f2fs_add_inline_entry+0x12a/0x2e0 [f2fs] [] __f2fs_add_link+0x45/0x4a0 [f2fs] [] ? f2fs_new_inode+0x146/0x220 [f2fs] [] f2fs_mknod+0x86/0xf0 [f2fs] [] vfs_mknod+0xe1/0x160 [] SyS_mknod+0x1f6/0x200 [] tracesys+0xe1/0xe6 Signed-off-by: Jaegeuk Kim --- fs/f2fs/acl.c | 144 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 138 insertions(+), 6 deletions(-) (limited to 'fs/f2fs/acl.c') diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c index 83b9b5a8d112..620745556828 100644 --- a/fs/f2fs/acl.c +++ b/fs/f2fs/acl.c @@ -162,7 +162,8 @@ fail: return ERR_PTR(-EINVAL); } -struct posix_acl *f2fs_get_acl(struct inode *inode, int type) +static struct posix_acl *__f2fs_get_acl(struct inode *inode, int type, + struct page *dpage) { int name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; void *value = NULL; @@ -172,12 +173,13 @@ struct posix_acl *f2fs_get_acl(struct inode *inode, int type) if (type == ACL_TYPE_ACCESS) name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS; - retval = f2fs_getxattr(inode, name_index, "", NULL, 0); + retval = f2fs_getxattr(inode, name_index, "", NULL, 0, dpage); if (retval > 0) { value = kmalloc(retval, GFP_F2FS_ZERO); if (!value) return ERR_PTR(-ENOMEM); - retval = f2fs_getxattr(inode, name_index, "", value, retval); + retval = f2fs_getxattr(inode, name_index, "", value, + retval, dpage); } if (retval > 0) @@ -194,6 +196,11 @@ struct posix_acl *f2fs_get_acl(struct inode *inode, int type) return acl; } +struct posix_acl *f2fs_get_acl(struct inode *inode, int type) +{ + return __f2fs_get_acl(inode, type, NULL); +} + static int __f2fs_set_acl(struct inode *inode, int type, struct posix_acl *acl, struct page *ipage) { @@ -249,12 +256,137 @@ int f2fs_set_acl(struct inode *inode, struct posix_acl *acl, int type) return __f2fs_set_acl(inode, type, acl, NULL); } -int f2fs_init_acl(struct inode *inode, struct inode *dir, struct page *ipage) +/* + * Most part of f2fs_acl_clone, f2fs_acl_create_masq, f2fs_acl_create + * are copied from posix_acl.c + */ +static struct posix_acl *f2fs_acl_clone(const struct posix_acl *acl, + gfp_t flags) +{ + struct posix_acl *clone = NULL; + + if (acl) { + int size = sizeof(struct posix_acl) + acl->a_count * + sizeof(struct posix_acl_entry); + clone = kmemdup(acl, size, flags); + if (clone) + atomic_set(&clone->a_refcount, 1); + } + return clone; +} + +static int f2fs_acl_create_masq(struct posix_acl *acl, umode_t *mode_p) +{ + struct posix_acl_entry *pa, *pe; + struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL; + umode_t mode = *mode_p; + int not_equiv = 0; + + /* assert(atomic_read(acl->a_refcount) == 1); */ + + FOREACH_ACL_ENTRY(pa, acl, pe) { + switch(pa->e_tag) { + case ACL_USER_OBJ: + pa->e_perm &= (mode >> 6) | ~S_IRWXO; + mode &= (pa->e_perm << 6) | ~S_IRWXU; + break; + + case ACL_USER: + case ACL_GROUP: + not_equiv = 1; + break; + + case ACL_GROUP_OBJ: + group_obj = pa; + break; + + case ACL_OTHER: + pa->e_perm &= mode | ~S_IRWXO; + mode &= pa->e_perm | ~S_IRWXO; + break; + + case ACL_MASK: + mask_obj = pa; + not_equiv = 1; + break; + + default: + return -EIO; + } + } + + if (mask_obj) { + mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO; + mode &= (mask_obj->e_perm << 3) | ~S_IRWXG; + } else { + if (!group_obj) + return -EIO; + group_obj->e_perm &= (mode >> 3) | ~S_IRWXO; + mode &= (group_obj->e_perm << 3) | ~S_IRWXG; + } + + *mode_p = (*mode_p & ~S_IRWXUGO) | mode; + return not_equiv; +} + +static int f2fs_acl_create(struct inode *dir, umode_t *mode, + struct posix_acl **default_acl, struct posix_acl **acl, + struct page *dpage) +{ + struct posix_acl *p; + int ret; + + if (S_ISLNK(*mode) || !IS_POSIXACL(dir)) + goto no_acl; + + p = __f2fs_get_acl(dir, ACL_TYPE_DEFAULT, dpage); + if (IS_ERR(p)) { + if (p == ERR_PTR(-EOPNOTSUPP)) + goto apply_umask; + return PTR_ERR(p); + } + + if (!p) + goto apply_umask; + + *acl = f2fs_acl_clone(p, GFP_NOFS); + if (!*acl) + return -ENOMEM; + + ret = f2fs_acl_create_masq(*acl, mode); + if (ret < 0) { + posix_acl_release(*acl); + return -ENOMEM; + } + + if (ret == 0) { + posix_acl_release(*acl); + *acl = NULL; + } + + if (!S_ISDIR(*mode)) { + posix_acl_release(p); + *default_acl = NULL; + } else { + *default_acl = p; + } + return 0; + +apply_umask: + *mode &= ~current_umask(); +no_acl: + *default_acl = NULL; + *acl = NULL; + return 0; +} + +int f2fs_init_acl(struct inode *inode, struct inode *dir, struct page *ipage, + struct page *dpage) { - struct posix_acl *default_acl, *acl; + struct posix_acl *default_acl = NULL, *acl = NULL; int error = 0; - error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); + error = f2fs_acl_create(dir, &inode->i_mode, &default_acl, &acl, dpage); if (error) return error; -- cgit v1.2.3