From cc314eef0128a807e50fa03baf2d0abc0647952c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 19 Aug 2005 18:02:56 -0700 Subject: Fix nasty ncpfs symlink handling bug. This bug could cause oopses and page state corruption, because ncpfs used the generic page-cache symlink handlign functions. But those functions only work if the page cache is guaranteed to be "stable", ie a page that was installed when the symlink walk was started has to still be installed in the page cache at the end of the walk. We could have fixed ncpfs to not use the generic helper routines, but it is in many ways much cleaner to instead improve on the symlink walking helper routines so that they don't require that absolute stability. We do this by allowing "follow_link()" to return a error-pointer as a cookie, which is fed back to the cleanup "put_link()" routine. This also simplifies NFS symlink handling. Signed-off-by: Linus Torvalds --- fs/sysfs/symlink.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/sysfs') diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index fae57c83a72..de402fa915f 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -151,17 +151,17 @@ static int sysfs_getlink(struct dentry *dentry, char * path) } -static int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) +static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) { int error = -ENOMEM; unsigned long page = get_zeroed_page(GFP_KERNEL); if (page) error = sysfs_getlink(dentry, (char *) page); nd_set_link(nd, error ? ERR_PTR(error) : (char *)page); - return 0; + return NULL; } -static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd) +static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) { char *page = nd_get_link(nd); if (!IS_ERR(page)) -- cgit v1.2.3-70-g09d2