diff options
Diffstat (limited to 'fs/jfs/xattr.c')
| -rw-r--r-- | fs/jfs/xattr.c | 402 |
1 files changed, 161 insertions, 241 deletions
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index 23aa5066b5a..46325d5c34f 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -4,22 +4,24 @@ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or + * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. - * + * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See * the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software + * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include <linux/capability.h> #include <linux/fs.h> #include <linux/xattr.h> #include <linux/posix_acl_xattr.h> +#include <linux/slab.h> #include <linux/quotaops.h> #include <linux/security.h> #include "jfs_incore.h" @@ -56,15 +58,15 @@ * * 0 4 4 + EA_SIZE(ea1) * +------------+-------------------+--------------------+----- - * | Overall EA | First FEA Element | Second FEA Element | ..... + * | Overall EA | First FEA Element | Second FEA Element | ..... * | List Size | | | * +------------+-------------------+--------------------+----- * * On-disk: * - * FEALISTs are stored on disk using blocks allocated by dbAlloc() and - * written directly. An EA list may be in-lined in the inode if there is - * sufficient room available. + * FEALISTs are stored on disk using blocks allocated by dbAlloc() and + * written directly. An EA list may be in-lined in the inode if there is + * sufficient room available. */ struct ea_buffer { @@ -83,62 +85,26 @@ struct ea_buffer { #define EA_NEW 0x0004 #define EA_MALLOC 0x0008 -/* Namespaces */ -#define XATTR_SYSTEM_PREFIX "system." -#define XATTR_SYSTEM_PREFIX_LEN (sizeof (XATTR_SYSTEM_PREFIX) - 1) - -#define XATTR_USER_PREFIX "user." -#define XATTR_USER_PREFIX_LEN (sizeof (XATTR_USER_PREFIX) - 1) - -#define XATTR_OS2_PREFIX "os2." -#define XATTR_OS2_PREFIX_LEN (sizeof (XATTR_OS2_PREFIX) - 1) -/* XATTR_SECURITY_PREFIX is defined in include/linux/xattr.h */ -#define XATTR_SECURITY_PREFIX_LEN (sizeof (XATTR_SECURITY_PREFIX) - 1) +static int is_known_namespace(const char *name) +{ + if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) && + strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) && + strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) && + strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) + return false; -#define XATTR_TRUSTED_PREFIX "trusted." -#define XATTR_TRUSTED_PREFIX_LEN (sizeof (XATTR_TRUSTED_PREFIX) - 1) + return true; +} /* * These three routines are used to recognize on-disk extended attributes * that are in a recognized namespace. If the attribute is not recognized, * "os2." is prepended to the name */ -static inline int is_os2_xattr(struct jfs_ea *ea) +static int is_os2_xattr(struct jfs_ea *ea) { - /* - * Check for "system." - */ - if ((ea->namelen >= XATTR_SYSTEM_PREFIX_LEN) && - !strncmp(ea->name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) - return FALSE; - /* - * Check for "user." - */ - if ((ea->namelen >= XATTR_USER_PREFIX_LEN) && - !strncmp(ea->name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) - return FALSE; - /* - * Check for "security." - */ - if ((ea->namelen >= XATTR_SECURITY_PREFIX_LEN) && - !strncmp(ea->name, XATTR_SECURITY_PREFIX, - XATTR_SECURITY_PREFIX_LEN)) - return FALSE; - /* - * Check for "trusted." - */ - if ((ea->namelen >= XATTR_TRUSTED_PREFIX_LEN) && - !strncmp(ea->name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) - return FALSE; - /* - * Add any other valid namespace prefixes here - */ - - /* - * We assume it's OS/2's flat namespace - */ - return TRUE; + return !is_known_namespace(ea->name); } static inline int name_size(struct jfs_ea *ea) @@ -169,9 +135,9 @@ static void ea_release(struct inode *inode, struct ea_buffer *ea_buf); /* * NAME: ea_write_inline - * + * * FUNCTION: Attempt to write an EA inline if area is available - * + * * PRE CONDITIONS: * Already verified that the specified EA is small enough to fit inline * @@ -230,10 +196,10 @@ static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist, /* * NAME: ea_write - * + * * FUNCTION: Write an EA for an inode - * - * PRE CONDITIONS: EA has been verified + * + * PRE CONDITIONS: EA has been verified * * PARAMETERS: * ip - Inode pointer @@ -274,14 +240,14 @@ static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size, nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits; /* Allocate new blocks to quota. */ - if (DQUOT_ALLOC_BLOCK(ip, nblocks)) { - return -EDQUOT; - } + rc = dquot_alloc_block(ip, nblocks); + if (rc) + return rc; rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno); if (rc) { /*Rollback quota allocation. */ - DQUOT_FREE_BLOCK(ip, nblocks); + dquot_free_block(ip, nblocks); return rc; } @@ -346,7 +312,7 @@ static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size, failed: /* Rollback quota allocation. */ - DQUOT_FREE_BLOCK(ip, nblocks); + dquot_free_block(ip, nblocks); dbFree(ip, blkno, nblocks); return rc; @@ -354,9 +320,9 @@ static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size, /* * NAME: ea_read_inline - * + * * FUNCTION: Read an inlined EA into user's buffer - * + * * PARAMETERS: * ip - Inode pointer * ealist - Pointer to buffer to fill in with EA @@ -386,9 +352,9 @@ static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist) /* * NAME: ea_read - * + * * FUNCTION: copy EA data into user's buffer - * + * * PARAMETERS: * ip - Inode pointer * ealist - Pointer to buffer to fill in with EA @@ -416,11 +382,11 @@ static int ea_read(struct inode *ip, struct jfs_ea_list *ealist) nbytes = sizeDXD(&ji->ea); if (!nbytes) { - jfs_error(sb, "ea_read: nbytes is 0"); + jfs_error(sb, "nbytes is 0\n"); return -EIO; } - /* + /* * Figure out how many blocks were allocated when this EA list was * originally written to disk. */ @@ -457,14 +423,14 @@ static int ea_read(struct inode *ip, struct jfs_ea_list *ealist) /* * NAME: ea_get - * + * * FUNCTION: Returns buffer containing existing extended attributes. * The size of the buffer will be the larger of the existing * attributes size, or min_size. * * The buffer, which may be inlined in the inode or in the - * page cache must be release by calling ea_release or ea_put - * + * page cache must be release by calling ea_release or ea_put + * * PARAMETERS: * inode - Inode pointer * ea_buf - Structure to be populated with ealist and its metadata @@ -516,7 +482,7 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) current_blocks = 0; } else { if (!(ji->ea.flag & DXD_EXTENT)) { - jfs_error(sb, "ea_get: invalid ea.flag)"); + jfs_error(sb, "invalid ea.flag\n"); return -EIO; } current_blocks = (ea_size + sb->s_blocksize - 1) >> @@ -552,7 +518,8 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) if (blocks_needed > current_blocks) { /* Allocate new blocks to quota. */ - if (DQUOT_ALLOC_BLOCK(inode, blocks_needed)) + rc = dquot_alloc_block(inode, blocks_needed); + if (rc) return -EDQUOT; quota_allocation = blocks_needed; @@ -604,7 +571,8 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) size_check: if (EALIST_SIZE(ea_buf->xattr) != ea_size) { printk(KERN_ERR "ea_get: invalid extended attribute\n"); - dump_mem("xattr", ea_buf->xattr, ea_size); + print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, + ea_buf->xattr, ea_size, 1); ea_release(inode, ea_buf); rc = -EIO; goto clean_up; @@ -615,7 +583,7 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) clean_up: /* Rollback quota allocation */ if (quota_allocation) - DQUOT_FREE_BLOCK(inode, quota_allocation); + dquot_free_block(inode, quota_allocation); return (rc); } @@ -690,7 +658,7 @@ static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf, /* If old blocks exist, they must be removed from quota allocation. */ if (old_blocks) - DQUOT_FREE_BLOCK(inode, old_blocks); + dquot_free_block(inode, old_blocks); inode->i_ctime = CURRENT_TIME; @@ -698,111 +666,32 @@ static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf, } /* - * can_set_system_xattr - * - * This code is specific to the system.* namespace. It contains policy - * which doesn't belong in the main xattr codepath. + * Most of the permission checking is done by xattr_permission in the vfs. + * We also need to verify that this is a namespace that we recognize. */ -static int can_set_system_xattr(struct inode *inode, const char *name, - const void *value, size_t value_len) -{ -#ifdef CONFIG_JFS_POSIX_ACL - struct posix_acl *acl; - int rc; - - if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) - return -EPERM; - - /* - * POSIX_ACL_XATTR_ACCESS is tied to i_mode - */ - if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0) { - acl = posix_acl_from_xattr(value, value_len); - if (IS_ERR(acl)) { - rc = PTR_ERR(acl); - printk(KERN_ERR "posix_acl_from_xattr returned %d\n", - rc); - return rc; - } - if (acl) { - mode_t mode = inode->i_mode; - rc = posix_acl_equiv_mode(acl, &mode); - posix_acl_release(acl); - if (rc < 0) { - printk(KERN_ERR - "posix_acl_equiv_mode returned %d\n", - rc); - return rc; - } - inode->i_mode = mode; - mark_inode_dirty(inode); - } - /* - * We're changing the ACL. Get rid of the cached one - */ - acl =JFS_IP(inode)->i_acl; - if (acl != JFS_ACL_NOT_CACHED) - posix_acl_release(acl); - JFS_IP(inode)->i_acl = JFS_ACL_NOT_CACHED; - - return 0; - } else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0) { - acl = posix_acl_from_xattr(value, value_len); - if (IS_ERR(acl)) { - rc = PTR_ERR(acl); - printk(KERN_ERR "posix_acl_from_xattr returned %d\n", - rc); - return rc; - } - posix_acl_release(acl); - - /* - * We're changing the default ACL. Get rid of the cached one - */ - acl =JFS_IP(inode)->i_default_acl; - if (acl && (acl != JFS_ACL_NOT_CACHED)) - posix_acl_release(acl); - JFS_IP(inode)->i_default_acl = JFS_ACL_NOT_CACHED; - - return 0; - } -#endif /* CONFIG_JFS_POSIX_ACL */ - return -EOPNOTSUPP; -} - static int can_set_xattr(struct inode *inode, const char *name, const void *value, size_t value_len) { - if (IS_RDONLY(inode)) - return -EROFS; - - if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) - return -EPERM; - - if(strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) == 0) + if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) { /* - * "system.*" + * This makes sure that we aren't trying to set an + * attribute in a different namespace by prefixing it + * with "os2." */ - return can_set_system_xattr(inode, name, value, value_len); - - if(strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) - return (capable(CAP_SYS_ADMIN) ? 0 : -EPERM); + if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN)) + return -EOPNOTSUPP; + return 0; + } -#ifdef CONFIG_JFS_SECURITY - if (strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) - == 0) - return 0; /* Leave it to the security module */ -#endif - - if((strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) != 0) && - (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) != 0)) + /* + * Don't allow setting an attribute in an unknown namespace. + */ + if (strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) && + strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) && + strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) return -EOPNOTSUPP; - if (!S_ISREG(inode->i_mode) && - (!S_ISDIR(inode->i_mode) || inode->i_mode &S_ISVTX)) - return -EPERM; - - return permission(inode, MAY_WRITE, NULL); + return 0; } int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, @@ -902,6 +791,19 @@ int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, /* Completely new ea list */ xattr_size = sizeof (struct jfs_ea_list); + /* + * The size of EA value is limitted by on-disk format up to + * __le16, there would be an overflow if the size is equal + * to XATTR_SIZE_MAX (65536). In order to avoid this issue, + * we can pre-checkup the value size against USHRT_MAX, and + * return -E2BIG in this case, which is consistent with the + * VFS setxattr interface. + */ + if (value_len >= USHRT_MAX) { + rc = -E2BIG; + goto release; + } + ea = (struct jfs_ea *) ((char *) ealist + xattr_size); ea->flag = 0; ea->namelen = namelen; @@ -916,7 +818,7 @@ int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, /* DEBUG - If we did this right, these number match */ if (xattr_size != new_size) { printk(KERN_ERR - "jfs_xsetattr: xattr_size = %d, new_size = %d\n", + "__jfs_setxattr: xattr_size = %d, new_size = %d\n", xattr_size, new_size); rc = -EINVAL; @@ -952,6 +854,14 @@ int jfs_setxattr(struct dentry *dentry, const char *name, const void *value, int rc; tid_t tid; + /* + * If this is a request for a synthetic attribute in the system.* + * namespace use the generic infrastructure to resolve a handler + * for it via sb->s_xattr. + */ + if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) + return generic_setxattr(dentry, name, value, value_len, flags); + if ((rc = can_set_xattr(inode, name, value, value_len))) return rc; @@ -961,33 +871,17 @@ int jfs_setxattr(struct dentry *dentry, const char *name, const void *value, } tid = txBegin(inode->i_sb, 0); - down(&ji->commit_sem); + mutex_lock(&ji->commit_mutex); rc = __jfs_setxattr(tid, dentry->d_inode, name, value, value_len, flags); if (!rc) rc = txCommit(tid, 1, &inode, 0); txEnd(tid); - up(&ji->commit_sem); + mutex_unlock(&ji->commit_mutex); return rc; } -static int can_get_xattr(struct inode *inode, const char *name) -{ -#ifdef CONFIG_JFS_SECURITY - if(strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) - return 0; -#endif - - if(strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) - return (capable(CAP_SYS_ADMIN) ? 0 : -EPERM); - - if(strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) == 0) - return 0; - - return permission(inode, MAY_READ, NULL); -} - ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data, size_t buf_size) { @@ -997,23 +891,8 @@ ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data, int xattr_size; ssize_t size; int namelen = strlen(name); - char *os2name = NULL; - int rc; char *value; - if ((rc = can_get_xattr(inode, name))) - return rc; - - if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) { - os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1, - GFP_KERNEL); - if (!os2name) - return -ENOMEM; - strcpy(os2name, name + XATTR_OS2_PREFIX_LEN); - name = os2name; - namelen -= XATTR_OS2_PREFIX_LEN; - } - down_read(&JFS_IP(inode)->xattr_sem); xattr_size = ea_get(inode, &ea_buf, 0); @@ -1051,8 +930,6 @@ ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data, out: up_read(&JFS_IP(inode)->xattr_sem); - kfree(os2name); - return size; } @@ -1061,6 +938,27 @@ ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data, { int err; + /* + * If this is a request for a synthetic attribute in the system.* + * namespace use the generic infrastructure to resolve a handler + * for it via sb->s_xattr. + */ + if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) + return generic_getxattr(dentry, name, data, buf_size); + + if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) { + /* + * skip past "os2." prefix + */ + name += XATTR_OS2_PREFIX_LEN; + /* + * Don't allow retrieving properly prefixed attributes + * by prepending them with "os2." + */ + if (is_known_namespace(name)) + return -EOPNOTSUPP; + } + err = __jfs_getxattr(dentry->d_inode, name, data, buf_size); return err; @@ -1101,7 +999,7 @@ ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size) /* compute required size of list */ for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { - if (can_list(ea)) + if (can_list(ea)) size += name_size(ea) + 1; } @@ -1116,7 +1014,7 @@ ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size) /* Copy attribute names to buffer */ buffer = data; for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { - if (can_list(ea)) { + if (can_list(ea)) { int namelen = copy_name(buffer, ea); buffer += namelen + 1; } @@ -1136,51 +1034,73 @@ int jfs_removexattr(struct dentry *dentry, const char *name) int rc; tid_t tid; + /* + * If this is a request for a synthetic attribute in the system.* + * namespace use the generic infrastructure to resolve a handler + * for it via sb->s_xattr. + */ + if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) + return generic_removexattr(dentry, name); + if ((rc = can_set_xattr(inode, name, NULL, 0))) return rc; tid = txBegin(inode->i_sb, 0); - down(&ji->commit_sem); + mutex_lock(&ji->commit_mutex); rc = __jfs_setxattr(tid, dentry->d_inode, name, NULL, 0, XATTR_REPLACE); if (!rc) rc = txCommit(tid, 1, &inode, 0); txEnd(tid); - up(&ji->commit_sem); + mutex_unlock(&ji->commit_mutex); return rc; } +/* + * List of handlers for synthetic system.* attributes. All real ondisk + * attributes are handled directly. + */ +const struct xattr_handler *jfs_xattr_handlers[] = { +#ifdef CONFIG_JFS_POSIX_ACL + &posix_acl_access_xattr_handler, + &posix_acl_default_xattr_handler, +#endif + NULL, +}; + + #ifdef CONFIG_JFS_SECURITY -int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir) +static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array, + void *fs_info) { - int rc; - size_t len; - void *value; - char *suffix; + const struct xattr *xattr; + tid_t *tid = fs_info; char *name; - - rc = security_inode_init_security(inode, dir, &suffix, &value, &len); - if (rc) { - if (rc == -EOPNOTSUPP) - return 0; - return rc; - } - name = kmalloc(XATTR_SECURITY_PREFIX_LEN + 1 + strlen(suffix), - GFP_NOFS); - if (!name) { - rc = -ENOMEM; - goto kmalloc_failed; + int err = 0; + + for (xattr = xattr_array; xattr->name != NULL; xattr++) { + name = kmalloc(XATTR_SECURITY_PREFIX_LEN + + strlen(xattr->name) + 1, GFP_NOFS); + if (!name) { + err = -ENOMEM; + break; + } + strcpy(name, XATTR_SECURITY_PREFIX); + strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); + + err = __jfs_setxattr(*tid, inode, name, + xattr->value, xattr->value_len, 0); + kfree(name); + if (err < 0) + break; } - strcpy(name, XATTR_SECURITY_PREFIX); - strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix); - - rc = __jfs_setxattr(tid, inode, name, value, len, 0); - - kfree(name); -kmalloc_failed: - kfree(suffix); - kfree(value); + return err; +} - return rc; +int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir, + const struct qstr *qstr) +{ + return security_inode_init_security(inode, dir, qstr, + &jfs_initxattrs, &tid); } #endif |