From b501611a6f78558eafcf09b228abd866d4ea5d9f Mon Sep 17 00:00:00 2001 From: Eric Van Hensbergen Date: Fri, 9 Sep 2005 13:04:27 -0700 Subject: [PATCH] [PATCH] v9fs: readlink extended mode check LANL reported some issues with random crashes during mount of legacy protocol servers (9P2000 versus 9P2000.u) -- crash was always happening in readlink (which should never happen in legacy mode). Added some sanity conditionals to the get_inode code which should prevent the errors LANL was seeing. Code tested benign through regression. Signed-off-by: Eric Van Hensbergen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/9p/vfs_inode.c | 35 ++++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 36fff087167f..0c13fc600049 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -44,6 +44,7 @@ #include "fid.h" static struct inode_operations v9fs_dir_inode_operations; +static struct inode_operations v9fs_dir_inode_operations_ext; static struct inode_operations v9fs_file_inode_operations; static struct inode_operations v9fs_symlink_inode_operations; @@ -232,6 +233,7 @@ v9fs_mistat2unix(struct v9fs_stat *mistat, struct stat *buf, struct inode *v9fs_get_inode(struct super_block *sb, int mode) { struct inode *inode = NULL; + struct v9fs_session_info *v9ses = sb->s_fs_info; dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode); @@ -250,6 +252,10 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) case S_IFBLK: case S_IFCHR: case S_IFSOCK: + if(!v9ses->extended) { + dprintk(DEBUG_ERROR, "special files without extended mode\n"); + return ERR_PTR(-EINVAL); + } init_special_inode(inode, inode->i_mode, inode->i_rdev); break; @@ -257,14 +263,21 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) inode->i_op = &v9fs_file_inode_operations; inode->i_fop = &v9fs_file_operations; break; + case S_IFLNK: + if(!v9ses->extended) { + dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n"); + return ERR_PTR(-EINVAL); + } + inode->i_op = &v9fs_symlink_inode_operations; + break; case S_IFDIR: inode->i_nlink++; - inode->i_op = &v9fs_dir_inode_operations; + if(v9ses->extended) + inode->i_op = &v9fs_dir_inode_operations_ext; + else + inode->i_op = &v9fs_dir_inode_operations; inode->i_fop = &v9fs_dir_operations; break; - case S_IFLNK: - inode->i_op = &v9fs_symlink_inode_operations; - break; default: dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n", mode, mode & S_IFMT); @@ -1284,7 +1297,7 @@ v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev) return retval; } -static struct inode_operations v9fs_dir_inode_operations = { +static struct inode_operations v9fs_dir_inode_operations_ext = { .create = v9fs_vfs_create, .lookup = v9fs_vfs_lookup, .symlink = v9fs_vfs_symlink, @@ -1299,6 +1312,18 @@ static struct inode_operations v9fs_dir_inode_operations = { .setattr = v9fs_vfs_setattr, }; +static struct inode_operations v9fs_dir_inode_operations = { + .create = v9fs_vfs_create, + .lookup = v9fs_vfs_lookup, + .unlink = v9fs_vfs_unlink, + .mkdir = v9fs_vfs_mkdir, + .rmdir = v9fs_vfs_rmdir, + .mknod = v9fs_vfs_mknod, + .rename = v9fs_vfs_rename, + .getattr = v9fs_vfs_getattr, + .setattr = v9fs_vfs_setattr, +}; + static struct inode_operations v9fs_file_inode_operations = { .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr,