diff options
| author | YueHaibing <yuehaibing@huawei.com> | 2023-07-15 17:25:43 +0800 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2023-07-17 09:46:26 +0200 |
| commit | 55c3b96074f3f9b0aee19bf93cd71af7516582bb (patch) | |
| tree | e9a1cecd0f980f79e85d0754ed3925268f780209 /net | |
| parent | ee8b94c8510ce64afe0b87ef548d23e00915fb10 (diff) | |
can: bcm: Fix UAF in bcm_proc_show()
BUG: KASAN: slab-use-after-free in bcm_proc_show+0x969/0xa80
Read of size 8 at addr ffff888155846230 by task cat/7862
CPU: 1 PID: 7862 Comm: cat Not tainted 6.5.0-rc1-00153-gc8746099c197 #230
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0xd5/0x150
print_report+0xc1/0x5e0
kasan_report+0xba/0xf0
bcm_proc_show+0x969/0xa80
seq_read_iter+0x4f6/0x1260
seq_read+0x165/0x210
proc_reg_read+0x227/0x300
vfs_read+0x1d5/0x8d0
ksys_read+0x11e/0x240
do_syscall_64+0x35/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Allocated by task 7846:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
__kasan_kmalloc+0x9e/0xa0
bcm_sendmsg+0x264b/0x44e0
sock_sendmsg+0xda/0x180
____sys_sendmsg+0x735/0x920
___sys_sendmsg+0x11d/0x1b0
__sys_sendmsg+0xfa/0x1d0
do_syscall_64+0x35/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Freed by task 7846:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_save_free_info+0x27/0x40
____kasan_slab_free+0x161/0x1c0
slab_free_freelist_hook+0x119/0x220
__kmem_cache_free+0xb4/0x2e0
rcu_core+0x809/0x1bd0
bcm_op is freed before procfs entry be removed in bcm_release(),
this lead to bcm_proc_show() may read the freed bcm_op.
Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20230715092543.15548-1-yuehaibing@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'net')
| -rw-r--r-- | net/can/bcm.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c index 9ba35685b043..9168114fc87f 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -1526,6 +1526,12 @@ static int bcm_release(struct socket *sock) lock_sock(sk); +#if IS_ENABLED(CONFIG_PROC_FS) + /* remove procfs entry */ + if (net->can.bcmproc_dir && bo->bcm_proc_read) + remove_proc_entry(bo->procname, net->can.bcmproc_dir); +#endif /* CONFIG_PROC_FS */ + list_for_each_entry_safe(op, next, &bo->tx_ops, list) bcm_remove_op(op); @@ -1561,12 +1567,6 @@ static int bcm_release(struct socket *sock) list_for_each_entry_safe(op, next, &bo->rx_ops, list) bcm_remove_op(op); -#if IS_ENABLED(CONFIG_PROC_FS) - /* remove procfs entry */ - if (net->can.bcmproc_dir && bo->bcm_proc_read) - remove_proc_entry(bo->procname, net->can.bcmproc_dir); -#endif /* CONFIG_PROC_FS */ - /* remove device reference */ if (bo->bound) { bo->bound = 0; |