01b39dcc95
Currently, there is a small window where ovl_obtain_alias() can race with ovl_instantiate() and create two different overlay inodes with the same underlying real non-dir non-hardlink inode. The race requires an adversary to guess the file handle of the yet to be created upper inode and decode the guessed file handle after ovl_creat_real(), but before ovl_instantiate(). This race does not affect overlay directory inodes, because those are decoded via ovl_lookup_real() and not with ovl_obtain_alias(). This patch fixes the race, by using inode_insert5() to add a newly created inode to cache. If the newly created inode apears to already exist in cache (hashed by the same real upper inode), we instantiate the dentry with the old inode and drop the new inode, instead of silently not hashing the new inode. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| copy_up.c | ||
| dir.c | ||
| export.c | ||
| inode.c | ||
| namei.c | ||
| overlayfs.h | ||
| ovl_entry.h | ||
| readdir.c | ||
| super.c | ||
| util.c | ||