kernel.git/security/smack/smackfs.c, branch linux-6.10.y

smackfs: Use rcu_assign_pointer() to ensure safe assignment in smk_set_cipso

2024-10-04T14:32:57Z

[ Upstream commit 2749749afa071f8a0e405605de9da615e771a7ce ] In the `smk_set_cipso` function, the `skp->smk_netlabel.attr.mls.cat` field is directly assigned to a new value without using the appropriate RCU pointer assignment functions. According to RCU usage rules, this is illegal and can lead to unpredictable behavior, including data inconsistencies and impossible-to-diagnose memory corruption issues. This possible bug was identified using a static analysis tool developed by myself, specifically designed to detect RCU-related issues. To address this, the assignment is now done using rcu_assign_pointer(), which ensures that the pointer assignment is done safely, with the necessary memory barriers and synchronization. This change prevents potential RCU dereference issues by ensuring that the `cat` field is safely updated while still adhering to RCU's requirements. Fixes: 0817534ff9ea ("smackfs: Fix use-after-free in netlbl_catmap_walk()") Signed-off-by: Jiawei Ye Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin

smackfs: Prevent underflow in smk_set_cipso()

2023-08-07T21:09:23Z

There is a upper bound to "catlen" but no lower bound to prevent negatives. I don't see that this necessarily causes a problem but we may as well be safe. Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel") Signed-off-by: Dan Carpenter Signed-off-by: Casey Schaufler

security: smack: smackfs: fix typo (lables->labels)

2023-08-07T21:09:23Z

Fix a spelling error in smakcfs. Signed-off-by: Tóth János Signed-off-by: Casey Schaufler

smackfs: Added check catlen

2023-02-21T19:22:02Z

If the catlen is 0, the memory for the netlbl_lsm_catmap structure must be allocated anyway, otherwise the check of such rules is not completed correctly. Signed-off-by: Denis Arefev Signed-off-by: Casey Schaufler

Merge tag 'pull-18-rc1-work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-06-05T02:00:05Z

Pull mount handling updates from Al Viro: "Cleanups (and one fix) around struct mount handling. The fix is usermode_driver.c one - once you've done kern_mount(), you must kern_unmount(); simple mntput() will end up with a leak. Several failure exits in there messed up that way... In practice you won't hit those particular failure exits without fault injection, though" * tag 'pull-18-rc1-work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: move mount-related externs from fs.h to mount.h blob_to_mnt(): kern_unmount() is needed to undo kern_mount() m->mnt_root->d_inode->i_sb is a weird way to spell m->mnt_sb... linux/mount.h: trim includes uninline may_mount() and don't opencode it in fspick(2)/fsopen(2)

smack: Remove redundant assignments

2022-05-23T18:12:08Z

Get rid of redundant assignments which end up in values not being read either because they are overwritten or the function ends. Reported by clang-tidy [deadcode.DeadStores] Signed-off-by: Michal Orzel Signed-off-by: Casey Schaufler

move mount-related externs from fs.h to mount.h

2022-05-20T03:25:48Z

Signed-off-by: Al Viro

smackfs: use netlbl_cfg_cipsov4_del() for deleting cipso_v4_doi

2021-10-22T15:46:53Z

syzbot is reporting UAF at cipso_v4_doi_search() [1], for smk_cipso_doi() is calling kfree() without removing from the cipso_v4_doi_list list after netlbl_cfg_cipsov4_map_add() returned an error. We need to use netlbl_cfg_cipsov4_del() in order to remove from the list and wait for RCU grace period before kfree(). Link: https://syzkaller.appspot.com/bug?extid=93dba5b91f0fed312cbd [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Fixes: 6c2e8ac0953fccdd ("netlabel: Update kernel configuration API") Signed-off-by: Casey Schaufler

smackfs: use __GFP_NOFAIL for smk_cipso_doi()

2021-10-22T15:46:44Z

syzbot is reporting kernel panic at smk_cipso_doi() due to memory allocation fault injection [1]. The reason for need to use panic() was not explained. But since no fix was proposed for 18 months, for now let's use __GFP_NOFAIL for utilizing syzbot resource on other bugs. Link: https://syzkaller.appspot.com/bug?extid=89731ccb6fec15ce1c22 [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Signed-off-by: Casey Schaufler

smackfs: Fix use-after-free in netlbl_catmap_walk()

2021-09-15T23:42:25Z

Syzkaller reported use-after-free bug as described in [1]. The bug is triggered when smk_set_cipso() tries to free stale category bitmaps while there are concurrent reader(s) using the same bitmaps. Wait for RCU grace period to finish before freeing the category bitmaps in smk_set_cipso(). This makes sure that there are no more readers using the stale bitmaps and freeing them should be safe. [1] https://lore.kernel.org/netdev/000000000000a814c505ca657a4e@google.com/ Reported-by: syzbot+3f91de0b813cc3d19a80@syzkaller.appspotmail.com Signed-off-by: Pawan Gupta Signed-off-by: Casey Schaufler