From: Miklos Szeredi For execute permission on a regular files we need to check if file has any execute bits at all, regardless of capabilites. This check is normally performed by generic_permission() but was also added to the case when the filesystem defines its own ->permission() method. In the latter case the filesystem should be responsible for performing this check. So create a helper function exec_permission() that checks returns -EACCESS if MAY_EXEC is present, the inode is a regular file and no execute bits are present in inode->i_mode. Call this function from filesystems which don't call generic_permission() from their ->permission() methods and which aren't already performing this check. Also remove the check from dentry_permission(). The new code should be equivalent to the old. Signed-off-by: Miklos Szeredi --- fs/cifs/cifsfs.c | 2 +- fs/coda/dir.c | 4 ++++ fs/coda/pioctl.c | 2 +- fs/hfs/inode.c | 2 +- fs/namei.c | 38 +++++++++++++++++++++++--------------- fs/nfs/dir.c | 3 +++ fs/proc/proc_sysctl.c | 3 +++ fs/smbfs/file.c | 6 +++--- include/linux/fs.h | 1 + 9 files changed, 40 insertions(+), 21 deletions(-) Index: linux-2.6/fs/cifs/cifsfs.c =================================================================== --- linux-2.6.orig/fs/cifs/cifsfs.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/cifs/cifsfs.c 2008-05-21 13:41:36.000000000 +0200 @@ -276,7 +276,7 @@ static int cifs_permission(struct dentry cifs_sb = CIFS_SB(inode->i_sb); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM) - return 0; + return exec_permission(inode, mask); else /* file mode might have been restricted at mount time on the client (above and beyond ACL on servers) for servers which do not support setting and viewing mode bits, Index: linux-2.6/fs/coda/dir.c =================================================================== --- linux-2.6.orig/fs/coda/dir.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/coda/dir.c 2008-05-21 13:41:36.000000000 +0200 @@ -145,6 +145,10 @@ int coda_permission(struct dentry *dentr if (!mask) return 0; + error = exec_permission(inode, mask); + if (error) + return error; + lock_kernel(); if (coda_cache_check(inode, mask)) Index: linux-2.6/fs/coda/pioctl.c =================================================================== --- linux-2.6.orig/fs/coda/pioctl.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/coda/pioctl.c 2008-05-21 13:41:36.000000000 +0200 @@ -43,7 +43,7 @@ const struct file_operations coda_ioctl_ /* the coda pioctl inode ops */ static int coda_ioctl_permission(struct dentry *dentry, int mask, int flags) { - return 0; + return exec_permission(dentry->d_inode, mask); } static int coda_pioctl(struct inode * inode, struct file * filp, Index: linux-2.6/fs/hfs/inode.c =================================================================== --- linux-2.6.orig/fs/hfs/inode.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/hfs/inode.c 2008-05-21 13:41:36.000000000 +0200 @@ -516,7 +516,7 @@ static int hfs_permission(struct dentry struct inode *inode = dentry->d_inode; if (S_ISREG(inode->i_mode) && mask & MAY_EXEC) - return 0; + return exec_permission(inode, mask); return generic_permission(inode, mask, NULL); } Index: linux-2.6/fs/nfs/dir.c =================================================================== --- linux-2.6.orig/fs/nfs/dir.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/nfs/dir.c 2008-05-21 13:41:36.000000000 +0200 @@ -1975,6 +1975,9 @@ force_lookup: res = PTR_ERR(cred); unlock_kernel(); out: + if (res == 0) + res = exec_permission(inode, mask); + dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n", inode->i_sb->s_id, inode->i_ino, mask, res); return res; Index: linux-2.6/fs/proc/proc_sysctl.c =================================================================== --- linux-2.6.orig/fs/proc/proc_sysctl.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/proc/proc_sysctl.c 2008-05-21 13:41:36.000000000 +0200 @@ -390,6 +390,9 @@ static int proc_sys_permission(struct de error = sysctl_perm(head->root, table, mask); out: sysctl_head_finish(head); + if (!error) + error = exec_permission(inode, mask); + return error; } Index: linux-2.6/fs/smbfs/file.c =================================================================== --- linux-2.6.orig/fs/smbfs/file.c 2008-05-21 13:41:30.000000000 +0200 +++ linux-2.6/fs/smbfs/file.c 2008-05-21 13:41:36.000000000 +0200 @@ -411,15 +411,15 @@ static int smb_file_permission(struct dentry *dentry, int mask, int flags) { int mode = dentry->d_inode->i_mode; - int error = 0; VERBOSE("mode=%x, mask=%x\n", mode, mask); /* Look at user permissions */ mode >>= 6; if ((mode & 7 & mask) != mask) - error = -EACCES; - return error; + return -EACCES; + + return exec_permission(dentry->d_inode, mask); } const struct file_operations smb_file_operations = Index: linux-2.6/fs/namei.c =================================================================== --- linux-2.6.orig/fs/namei.c 2008-05-21 13:41:34.000000000 +0200 +++ linux-2.6/fs/namei.c 2008-05-21 13:41:36.000000000 +0200 @@ -226,6 +226,26 @@ int generic_permission(struct inode *ino return -EACCES; } +/** + * exec_permission - check for general execute permission on file + * @inode: inode to check access rights for + * @mask: right to check for + * + * Exec permission on a regular file is denied if none of the execute + * bits are set. + * + * This needs to be called by filesystems which define a + * ->permission() method, and don't call generic_permission(). + */ +int exec_permission(struct inode *inode, int mask) +{ + if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) && + !(inode->i_mode & S_IXUGO)) + return -EACCES; + + return 0; +} + int dentry_permission(struct dentry *dentry, int mask, int flags) { struct inode *inode = dentry->d_inode; @@ -250,23 +270,11 @@ int dentry_permission(struct dentry *den /* Ordinary permission routines do not understand MAY_APPEND. */ submask = mask & ~MAY_APPEND; - if (inode->i_op && inode->i_op->permission) { + if (inode->i_op && inode->i_op->permission) retval = inode->i_op->permission(dentry, submask, flags); - if (!retval) { - /* - * Exec permission on a regular file is denied if none - * of the execute bits are set. - * - * This check should be done by the ->permission() - * method. - */ - if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) && - !(inode->i_mode & S_IXUGO)) - return -EACCES; - } - } else { + else retval = generic_permission(inode, submask, NULL); - } + if (retval) return retval; Index: linux-2.6/include/linux/fs.h =================================================================== --- linux-2.6.orig/include/linux/fs.h 2008-05-21 13:41:34.000000000 +0200 +++ linux-2.6/include/linux/fs.h 2008-05-21 13:41:36.000000000 +0200 @@ -1761,6 +1761,7 @@ extern int path_setattr(struct path *, s extern int dentry_permission(struct dentry *, int, int); extern int generic_permission(struct inode *, int, int (*check_acl)(struct inode *, int)); +extern int exec_permission(struct inode *, int); extern int get_write_access(struct inode *); extern int deny_write_access(struct file *); -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/