mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-24 20:54:10 +08:00
bf4b2fee99
I have vehemently opposed adding a "permissive" mode to Smack for the simple reasons that it would be subject to massive abuse and that developers refuse to turn it off come product release. I still believe that this is true, and still refuse to add a general "permissive mode". So don't ask again. Bumjin Im suggested an approach that addresses most of the concerns, and I have implemented it here. I still believe that we'd be better off without this sort of thing, but it looks like this minimizes the abuse potential. Firstly, you have to configure Smack Bringup Mode. That allows for "release" software to be ammune from abuse. Second, only one label gets to be "permissive" at a time. You can use it for debugging, but that's about it. A label written to smackfs/unconfined is treated specially. If either the subject or object label of an access check matches the "unconfined" label, and the access would not have been allowed otherwise an audit record and a console message are generated. The audit record "request" string is marked with either "(US)" or "(UO)", to indicate that the request was granted because of an unconfined label. The fact that an inode was accessed by an unconfined label is remembered, and subsequent accesses to that "impure" object are noted in the log. The impurity is not stored in the filesystem, so a file mislabled as a side effect of using an unconfined label may still cause concern after a reboot. So, it's there, it's dangerous, but so many application developers seem incapable of living without it I have given in. I've tried to make it as safe as I can, but in the end it's still a chain saw. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> |
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| smack_access.c | ||
| smack_lsm.c | ||
| smack_netfilter.c | ||
| smack.h | ||
| smackfs.c | ||