diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2025-05-28 10:55:21 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2025-06-05 14:37:58 +0200 |
| commit | 8337204c58899fe422db765b481711eb2d95eb0b (patch) | |
| tree | ba54af5faeaf7a698f584e25e2b2d9b6875a70cc | |
| parent | 0ecb4232fc65e659ca7020f8bb2e0fc347acfb7d (diff) | |
futex: Handle invalid node numbers supplied by user
syzbot used a negative node number which was not rejected early and led
to invalid memory access in node_possible().
Reject negative node numbers except for FUTEX_NO_NODE.
[bigeasy: Keep the FUTEX_NO_NODE check]
Closes: https://lore.kernel.org/all/6835bfe3.a70a0220.253bc2.00b5.GAE@google.com/
Fixes: cec199c5e39bd ("futex: Implement FUTEX2_NUMA")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: syzbot+9afaf6749e3a7aa1bdf3@syzkaller.appspotmail.com
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250528085521.1938355-4-bigeasy@linutronix.de
| -rw-r--r-- | kernel/futex/core.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/futex/core.c b/kernel/futex/core.c index 565f9717c6ca..b652d2f60c40 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -583,8 +583,8 @@ int get_futex_key(u32 __user *uaddr, unsigned int flags, union futex_key *key, if (futex_get_value(&node, naddr)) return -EFAULT; - if (node != FUTEX_NO_NODE && - (node >= MAX_NUMNODES || !node_possible(node))) + if ((node != FUTEX_NO_NODE) && + ((unsigned int)node >= MAX_NUMNODES || !node_possible(node))) return -EINVAL; } |