From 33852a1f2bb014e4047a844556c0d76a2f790c37 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 19 Jun 2008 14:20:11 -0400 Subject: NFS: Reduce the NFS mount code stack usage. This appears to fix the Oops reported in http://bugzilla.kernel.org/show_bug.cgi?id=10826 Signed-off-by: Trond Myklebust --- fs/nfs/super.c | 68 ++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 40 insertions(+), 28 deletions(-) diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 2a4a024a4e7..dac663dc561 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -1216,8 +1216,6 @@ static int nfs_validate_mount_data(void *options, { struct nfs_mount_data *data = (struct nfs_mount_data *)options; - memset(args, 0, sizeof(*args)); - if (data == NULL) goto out_no_data; @@ -1585,24 +1583,29 @@ static int nfs_get_sb(struct file_system_type *fs_type, { struct nfs_server *server = NULL; struct super_block *s; - struct nfs_fh mntfh; - struct nfs_parsed_mount_data data; + struct nfs_parsed_mount_data *data; + struct nfs_fh *mntfh; struct dentry *mntroot; int (*compare_super)(struct super_block *, void *) = nfs_compare_super; struct nfs_sb_mountdata sb_mntdata = { .mntflags = flags, }; - int error; + int error = -ENOMEM; - security_init_mnt_opts(&data.lsm_opts); + data = kzalloc(sizeof(*data), GFP_KERNEL); + mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL); + if (data == NULL || mntfh == NULL) + goto out_free_fh; + + security_init_mnt_opts(&data->lsm_opts); /* Validate the mount data */ - error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name); + error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name); if (error < 0) goto out; /* Get a volume representation */ - server = nfs_create_server(&data, &mntfh); + server = nfs_create_server(data, mntfh); if (IS_ERR(server)) { error = PTR_ERR(server); goto out; @@ -1630,16 +1633,16 @@ static int nfs_get_sb(struct file_system_type *fs_type, if (!s->s_root) { /* initial superblock/root creation */ - nfs_fill_super(s, &data); + nfs_fill_super(s, data); } - mntroot = nfs_get_root(s, &mntfh); + mntroot = nfs_get_root(s, mntfh); if (IS_ERR(mntroot)) { error = PTR_ERR(mntroot); goto error_splat_super; } - error = security_sb_set_mnt_opts(s, &data.lsm_opts); + error = security_sb_set_mnt_opts(s, &data->lsm_opts); if (error) goto error_splat_root; @@ -1649,9 +1652,12 @@ static int nfs_get_sb(struct file_system_type *fs_type, error = 0; out: - kfree(data.nfs_server.hostname); - kfree(data.mount_server.hostname); - security_free_mnt_opts(&data.lsm_opts); + kfree(data->nfs_server.hostname); + kfree(data->mount_server.hostname); + security_free_mnt_opts(&data->lsm_opts); +out_free_fh: + kfree(mntfh); + kfree(data); return error; out_err_nosb: @@ -1800,8 +1806,6 @@ static int nfs4_validate_mount_data(void *options, struct nfs4_mount_data *data = (struct nfs4_mount_data *)options; char *c; - memset(args, 0, sizeof(*args)); - if (data == NULL) goto out_no_data; @@ -1959,26 +1963,31 @@ out_no_client_address: static int nfs4_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt) { - struct nfs_parsed_mount_data data; + struct nfs_parsed_mount_data *data; struct super_block *s; struct nfs_server *server; - struct nfs_fh mntfh; + struct nfs_fh *mntfh; struct dentry *mntroot; int (*compare_super)(struct super_block *, void *) = nfs_compare_super; struct nfs_sb_mountdata sb_mntdata = { .mntflags = flags, }; - int error; + int error = -ENOMEM; - security_init_mnt_opts(&data.lsm_opts); + data = kzalloc(sizeof(*data), GFP_KERNEL); + mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL); + if (data == NULL || mntfh == NULL) + goto out_free_fh; + + security_init_mnt_opts(&data->lsm_opts); /* Validate the mount data */ - error = nfs4_validate_mount_data(raw_data, &data, dev_name); + error = nfs4_validate_mount_data(raw_data, data, dev_name); if (error < 0) goto out; /* Get a volume representation */ - server = nfs4_create_server(&data, &mntfh); + server = nfs4_create_server(data, mntfh); if (IS_ERR(server)) { error = PTR_ERR(server); goto out; @@ -2009,13 +2018,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type, nfs4_fill_super(s); } - mntroot = nfs4_get_root(s, &mntfh); + mntroot = nfs4_get_root(s, mntfh); if (IS_ERR(mntroot)) { error = PTR_ERR(mntroot); goto error_splat_super; } - error = security_sb_set_mnt_opts(s, &data.lsm_opts); + error = security_sb_set_mnt_opts(s, &data->lsm_opts); if (error) goto error_splat_root; @@ -2025,10 +2034,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type, error = 0; out: - kfree(data.client_address); - kfree(data.nfs_server.export_path); - kfree(data.nfs_server.hostname); - security_free_mnt_opts(&data.lsm_opts); + kfree(data->client_address); + kfree(data->nfs_server.export_path); + kfree(data->nfs_server.hostname); + security_free_mnt_opts(&data->lsm_opts); +out_free_fh: + kfree(mntfh); + kfree(data); return error; out_free: -- cgit v1.2.3 From b7e2445737ff69cef892b6fd9cd71cae2c9e9515 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 19 Jun 2008 15:21:11 -0400 Subject: NFS: Fix filehandle size comparisons in the mount code Fix a sign issue in xdr_decode_fhstatus3() Fix incorrect comparison in nfs_validate_mount_data() Signed-off-by: Trond Myklebust --- fs/nfs/mount_clnt.c | 5 +++-- fs/nfs/super.c | 8 ++++---- 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c index 49c7cd0502c..779d2eb649c 100644 --- a/fs/nfs/mount_clnt.c +++ b/fs/nfs/mount_clnt.c @@ -130,10 +130,11 @@ static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p, struct mnt_fhstatus *res) { struct nfs_fh *fh = res->fh; + unsigned size; if ((res->status = ntohl(*p++)) == 0) { - int size = ntohl(*p++); - if (size <= NFS3_FHSIZE) { + size = ntohl(*p++); + if (size <= NFS3_FHSIZE && size != 0) { fh->size = size; memcpy(fh->data, p, size); } else diff --git a/fs/nfs/super.c b/fs/nfs/super.c index dac663dc561..614efeed543 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -1249,13 +1249,13 @@ static int nfs_validate_mount_data(void *options, case 5: memset(data->context, 0, sizeof(data->context)); case 6: - if (data->flags & NFS_MOUNT_VER3) + if (data->flags & NFS_MOUNT_VER3) { + if (data->root.size > NFS3_FHSIZE || data->root.size == 0) + goto out_invalid_fh; mntfh->size = data->root.size; - else + } else mntfh->size = NFS2_FHSIZE; - if (mntfh->size > sizeof(mntfh->data)) - goto out_invalid_fh; memcpy(mntfh->data, data->root.data, mntfh->size); if (mntfh->size < sizeof(mntfh->data)) -- cgit v1.2.3 From 03fa9e84e5dc10aeacb0e4eb2f708cd9fc36a5b8 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 5 Jun 2008 16:02:35 -0400 Subject: NFS: nfs_updatepage(): don't mark page as dirty if an error occurred Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 6d8ace3e325..f333848fd3b 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -739,12 +739,13 @@ int nfs_updatepage(struct file *file, struct page *page, } status = nfs_writepage_setup(ctx, page, offset, count); - __set_page_dirty_nobuffers(page); + if (status < 0) + nfs_set_pageerror(page); + else + __set_page_dirty_nobuffers(page); dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", status, (long long)i_size_read(inode)); - if (status < 0) - nfs_set_pageerror(page); return status; } -- cgit v1.2.3