From 8bb79224b87aab92071e94d46e70bd160d89bf34 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 16 Jul 2008 09:51:03 -0400 Subject: [PATCH] [PATCH] permission checks for chdir need special treatment only on the last step ... so we ought to pass MAY_CHDIR to vfs_permission() instead of having it triggered on every step of preceding pathname resolution. LOOKUP_CHDIR is killed by that. Signed-off-by: Al Viro --- fs/namei.c | 2 -- fs/open.c | 5 ++--- include/linux/namei.h | 1 - 3 files changed, 2 insertions(+), 6 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index ae0e56fdb74..6c76e1ee9c4 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -268,8 +268,6 @@ int permission(struct inode *inode, int mask, struct nameidata *nd) if (nd) { if (nd->flags & LOOKUP_ACCESS) extra |= MAY_ACCESS; - if (nd->flags & LOOKUP_CHDIR) - extra |= MAY_CHDIR; if (nd->flags & LOOKUP_OPEN) extra |= MAY_OPEN; } diff --git a/fs/open.c b/fs/open.c index b2e4c93aed0..8e02d42bfe4 100644 --- a/fs/open.c +++ b/fs/open.c @@ -501,12 +501,11 @@ asmlinkage long sys_chdir(const char __user * filename) struct nameidata nd; int error; - error = __user_walk(filename, - LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd); + error = __user_walk(filename, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &nd); if (error) goto out; - error = vfs_permission(&nd, MAY_EXEC); + error = vfs_permission(&nd, MAY_EXEC | MAY_CHDIR); if (error) goto dput_and_out; diff --git a/include/linux/namei.h b/include/linux/namei.h index 24d88e98a62..3cf62d26d49 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -55,7 +55,6 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; #define LOOKUP_OPEN (0x0100) #define LOOKUP_CREATE (0x0200) #define LOOKUP_ACCESS (0x0400) -#define LOOKUP_CHDIR (0x0800) extern int __user_walk(const char __user *, unsigned, struct nameidata *); extern int __user_walk_fd(int dfd, const char __user *, unsigned, struct nameidata *); -- 2.20.1