diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-06-18 14:08:44 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-06-27 11:11:44 +0100 |
| commit | 5fe1b23a2f87f43aeeac51e08819cbc6fd808cbc (patch) | |
| tree | b7ea5bd3390afab9f19ccd770713f954111a9c14 | |
| parent | f4d80b16ecc4229f7e6345158ef34c36be323f0e (diff) | |
net: atm: fix /proc/net/atm/lec handling
[ Upstream commit d03b79f459c7935cff830d98373474f440bd03ae ]
/proc/net/atm/lec must ensure safety against dev_lec[] changes.
It appears it had dev_put() calls without prior dev_hold(),
leading to imbalance and UAF.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Francois Romieu <romieu@fr.zoreil.com> # Minor atm contributor
Link: https://patch.msgid.link/20250618140844.1686882-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/atm/lec.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/atm/lec.c b/net/atm/lec.c index 09c042e1e469..42e8047c6510 100644 --- a/net/atm/lec.c +++ b/net/atm/lec.c @@ -909,7 +909,6 @@ static void *lec_itf_walk(struct lec_state *state, loff_t *l) v = (dev && netdev_priv(dev)) ? lec_priv_walk(state, l, netdev_priv(dev)) : NULL; if (!v && dev) { - dev_put(dev); /* Partial state reset for the next time we get called */ dev = NULL; } @@ -933,6 +932,7 @@ static void *lec_seq_start(struct seq_file *seq, loff_t *pos) { struct lec_state *state = seq->private; + mutex_lock(&lec_mutex); state->itf = 0; state->dev = NULL; state->locked = NULL; @@ -950,8 +950,9 @@ static void lec_seq_stop(struct seq_file *seq, void *v) if (state->dev) { spin_unlock_irqrestore(&state->locked->lec_arp_lock, state->flags); - dev_put(state->dev); + state->dev = NULL; } + mutex_unlock(&lec_mutex); } static void *lec_seq_next(struct seq_file *seq, void *v, loff_t *pos) |