massage generic_permission() to treat directories on a separate path

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2011-06-20 19:55:42 -04:00
parent eecdd358b4
commit d594e7ec4d
1 changed files with 13 additions and 4 deletions

View File

@ -235,12 +235,21 @@ int generic_permission(struct inode *inode, int mask)
if (ret != -EACCES)
return ret;
if (S_ISDIR(inode->i_mode)) {
/* DACs are overridable for directories */
if (ns_capable(inode_userns(inode), CAP_DAC_OVERRIDE))
return 0;
if (!(mask & MAY_WRITE))
if (ns_capable(inode_userns(inode), CAP_DAC_READ_SEARCH))
return 0;
return -EACCES;
}
/*
* Read/write DACs are always overridable.
* Executable DACs are overridable for all directories and
* for non-directories that have least one exec bit set.
* Executable DACs are overridable when there is
* at least one exec bit set.
*/
if (!(mask & MAY_EXEC) || execute_ok(inode))
if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
if (ns_capable(inode_userns(inode), CAP_DAC_OVERRIDE))
return 0;
@ -248,7 +257,7 @@ int generic_permission(struct inode *inode, int mask)
* Searching includes executable on directories, else just read.
*/
mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
if (mask == MAY_READ || (S_ISDIR(inode->i_mode) && !(mask & MAY_WRITE)))
if (mask == MAY_READ)
if (ns_capable(inode_userns(inode), CAP_DAC_READ_SEARCH))
return 0;