X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fattr.c;h=0815e93bb487e0651619d942b6bd78d7fe6a2e89;hb=328efbab0f8ae1617448917906a12e5f568553b6;hp=f4360192a9387614b090e4ee6b467c6ee9ae082d;hpb=da9592edebceeba1b9301beafe80ec8b9c2db0ce;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/attr.c b/fs/attr.c index f436019..0815e93 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -12,13 +12,12 @@ #include #include #include -#include #include /* Taken over from the old code... */ /* POSIX UID/GID verification for setting inode attributes. */ -int inode_change_ok(struct inode *inode, struct iattr *attr) +int inode_change_ok(const struct inode *inode, struct iattr *attr) { int retval = -EPERM; unsigned int ia_valid = attr->ia_valid; @@ -60,9 +59,51 @@ fine: error: return retval; } - EXPORT_SYMBOL(inode_change_ok); +/** + * inode_newsize_ok - may this inode be truncated to a given size + * @inode: the inode to be truncated + * @offset: the new size to assign to the inode + * @Returns: 0 on success, -ve errno on failure + * + * inode_newsize_ok will check filesystem limits and ulimits to check that the + * new inode size is within limits. inode_newsize_ok will also send SIGXFSZ + * when necessary. Caller must not proceed with inode size change if failure is + * returned. @inode must be a file (not directory), with appropriate + * permissions to allow truncate (inode_newsize_ok does NOT check these + * conditions). + * + * inode_newsize_ok must be called with i_mutex held. + */ +int inode_newsize_ok(const struct inode *inode, loff_t offset) +{ + if (inode->i_size < offset) { + unsigned long limit; + + limit = rlimit(RLIMIT_FSIZE); + if (limit != RLIM_INFINITY && offset > limit) + goto out_sig; + if (offset > inode->i_sb->s_maxbytes) + goto out_big; + } else { + /* + * truncation of in-use swapfiles is disallowed - it would + * cause subsequent swapout to scribble on the now-freed + * blocks. + */ + if (IS_SWAPFILE(inode)) + return -ETXTBSY; + } + + return 0; +out_sig: + send_sig(SIGXFSZ, current, 0); +out_big: + return -EFBIG; +} +EXPORT_SYMBOL(inode_newsize_ok); + int inode_setattr(struct inode * inode, struct iattr * attr) { unsigned int ia_valid = attr->ia_valid; @@ -170,13 +211,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr) error = inode->i_op->setattr(dentry, attr); } else { error = inode_change_ok(inode, attr); - if (!error) { - if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || - (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) - error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0; - if (!error) - error = inode_setattr(inode, attr); - } + if (!error) + error = inode_setattr(inode, attr); } if (ia_valid & ATTR_SIZE)