TencentOS-kernel/security
Sabyrzhan Tasbolatov f6272b7262 smackfs: restrict bytes count in smackfs write functions
commit 7ef4c19d245f3dc233fd4be5acea436edd1d83d8 upstream.

syzbot found WARNINGs in several smackfs write operations where
bytes count is passed to memdup_user_nul which exceeds
GFP MAX_ORDER. Check count size if bigger than PAGE_SIZE.

Per smackfs doc, smk_write_net4addr accepts any label or -CIPSO,
smk_write_net6addr accepts any label or -DELETE. I couldn't find
any general rule for other label lengths except SMK_LABELLEN,
SMK_LONGLABEL, SMK_CIPSOMAX which are documented.

Let's constrain, in general, smackfs label lengths for PAGE_SIZE.
Although fuzzer crashes write to smackfs/netlabel on 0x400000 length.

Here is a quick way to reproduce the WARNING:
python -c "print('A' * 0x400000)" > /sys/fs/smackfs/netlabel

Reported-by: syzbot+a71a442385a0b2815497@syzkaller.appspotmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:52:44 +08:00
..
apparmor apparmor: ensure that dfa state tables have entries 2021-03-16 16:32:02 +08:00
integrity certs: Fix blacklist flag type confusion 2021-04-12 12:52:25 +08:00
keys KEYS: trusted: Fix migratable=1 failing 2021-04-12 12:52:35 +08:00
loadpin Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lockdown lockdown: Allow unprivileged users to see lockdown status 2021-03-16 16:29:19 +08:00
safesetid Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
selinux selinux: fix inode_doinit_with_dentry() LABEL_INVALID error handling 2021-03-16 16:42:41 +08:00
smack smackfs: restrict bytes count in smackfs write functions 2021-04-12 12:52:44 +08:00
tomoyo Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
yama Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig.hardening Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Makefile Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
commoncap.c capabilities: Don't allow writing ambiguous v3 file capabilities 2021-04-12 12:52:22 +08:00
device_cgroup.c device_cgroup: Fix RCU list debugging warning 2021-03-16 16:37:29 +08:00
inode.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lsm_audit.c dump_common_audit_data(): fix racy accesses to ->d_name 2021-04-12 12:51:25 +08:00
min_addr.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
security.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00