9c5e45df21
If a keyring contains more than 16 keyrings (the capacity of a single node in the associative array) then those keyrings are split over multiple nodes arranged as a tree. If search_nested_keyrings() is called to search the keyring then it will attempt to manually walk over just the 0 branch of the associative array tree where all the keyring links are stored. This works provided the key is found before the algorithm steps from one node containing keyrings to a child node or if there are sufficiently few keyring links that the keyrings are all in one node. However, if the algorithm does need to step from a node to a child node, it doesn't change the node pointer unless a shortcut also gets transited. This means that the algorithm will keep scanning the same node over and over again without terminating and without returning. To fix this, move the internal-pointer-to-node translation from inside the shortcut transit handler so that it applies it to node arrival as well. This can be tested by: r=`keyctl newring sandbox @s` for ((i=0; i<=16; i++)); do keyctl newring ring$i $r; done for ((i=0; i<=16; i++)); do keyctl add user a$i a %:ring$i; done for ((i=0; i<=16; i++)); do keyctl search $r user a$i; done for ((i=17; i<=20; i++)); do keyctl search $r user a$i; done The searches should all complete successfully (or with an error for 17-20), but instead one or more of them will hang. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Stephen Gallagher <sgallagh@redhat.com> |
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| .. | ||
| apparmor | ||
| integrity | ||
| keys | ||
| selinux | ||
| smack | ||
| tomoyo | ||
| yama | ||
| capability.c | ||
| commoncap.c | ||
| device_cgroup.c | ||
| inode.c | ||
| Kconfig | ||
| lsm_audit.c | ||
| Makefile | ||
| min_addr.c | ||
| security.c | ||