This patch addresses a flaw in LSM, where there is no mediation of readv() and writev() in for 32-bit compatible apps using a 64-bit kernel. This bug was discovered and fixed initially in the native readv/writev code [1], but was not fixed in the compat code. Thanks to Al for spotting this one. [1] http://lwn.net/Articles/154282/
Unified · Split
| @@ -1217,6 +1217,10 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, · 1216 unmodified lines | |||
| 1217 | if (ret < 0) | 1217 | if (ret < 0) |
| 1218 | goto out; | 1218 | goto out; |
| 1219 | 1219 | ||
| 1220 | ret = security_file_permission(file, type == READ ? MAY_READ:MAY_WRITE); | ||
| 1221 | if (ret) | ||
| 1222 | goto out; | ||
| 1223 | |||
| 1220 | fnv = NULL; | 1224 | fnv = NULL; |
| 1221 | if (type == READ) { | 1225 | if (type == READ) { |
| 1222 | fn = file->f_op->read; | 1226 | fn = file->f_op->read; |