Message ID | bbc81ddb35efd09b89e2f8f6af72866bcc9c1550.1655869357.git.duoming@zju.edu.cn (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | Fix UAF and null-ptr-deref bugs in rose protocol | expand |
Context | Check | Description |
---|---|---|
netdev/tree_selection | success | Clearly marked for net |
netdev/fixes_present | success | Fixes tag present in non-next series |
netdev/subject_prefix | success | Link |
netdev/cover_letter | success | Series has a cover letter |
netdev/patch_count | success | Link |
netdev/header_inline | success | No static functions without inline keyword in header files |
netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
netdev/cc_maintainers | success | CCed 7 of 7 maintainers |
netdev/build_clang | success | Errors and warnings before: 0 this patch: 0 |
netdev/module_param | success | Was 0 now: 0 |
netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
netdev/check_selftest | success | No net selftest shell script |
netdev/verify_fixes | success | Fixes tag looks correct |
netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 93 lines checked |
netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
netdev/source_inline | success | Was 0 now: 0 |
On Wed, 2022-06-22 at 12:01 +0800, Duoming Zhou wrote: > There are UAF bugs in rose_heartbeat_expiry(), rose_timer_expiry() > and rose_idletimer_expiry(). The root cause is that del_timer() > could not stop the timer handler that is running and the refcount > of sock is not managed properly. > > One of the UAF bugs is shown below: > > (thread 1) | (thread 2) > | rose_bind > | rose_connect > | rose_start_heartbeat > rose_release | (wait a time) > case ROSE_STATE_0 | > rose_destroy_socket | rose_heartbeat_expiry > rose_stop_heartbeat | > sock_put(sk) | ... > sock_put(sk) // FREE | > | bh_lock_sock(sk) // USE > > The sock is deallocated by sock_put() in rose_release() and > then used by bh_lock_sock() in rose_heartbeat_expiry(). > > Although rose_destroy_socket() calls rose_stop_heartbeat(), > it could not stop the timer that is running. > > The KASAN report triggered by POC is shown below: > > BUG: KASAN: use-after-free in _raw_spin_lock+0x5a/0x110 > Write of size 4 at addr ffff88800ae59098 by task swapper/3/0 > ... > Call Trace: > <IRQ> > dump_stack_lvl+0xbf/0xee > print_address_description+0x7b/0x440 > print_report+0x101/0x230 > ? irq_work_single+0xbb/0x140 > ? _raw_spin_lock+0x5a/0x110 > kasan_report+0xed/0x120 > ? _raw_spin_lock+0x5a/0x110 > kasan_check_range+0x2bd/0x2e0 > _raw_spin_lock+0x5a/0x110 > rose_heartbeat_expiry+0x39/0x370 > ? rose_start_heartbeat+0xb0/0xb0 > call_timer_fn+0x2d/0x1c0 > ? rose_start_heartbeat+0xb0/0xb0 > expire_timers+0x1f3/0x320 > __run_timers+0x3ff/0x4d0 > run_timer_softirq+0x41/0x80 > __do_softirq+0x233/0x544 > irq_exit_rcu+0x41/0xa0 > sysvec_apic_timer_interrupt+0x8c/0xb0 > </IRQ> > <TASK> > asm_sysvec_apic_timer_interrupt+0x1b/0x20 > RIP: 0010:default_idle+0xb/0x10 > RSP: 0018:ffffc9000012fea0 EFLAGS: 00000202 > RAX: 000000000000bcae RBX: ffff888006660f00 RCX: 000000000000bcae > RDX: 0000000000000001 RSI: ffffffff843a11c0 RDI: ffffffff843a1180 > RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffed100da36d46 > R10: dfffe9100da36d47 R11: ffffffff83cf0950 R12: 0000000000000000 > R13: 1ffff11000ccc1e0 R14: ffffffff8542af28 R15: dffffc0000000000 > ... > Allocated by task 146: > __kasan_kmalloc+0xc4/0xf0 > sk_prot_alloc+0xdd/0x1a0 > sk_alloc+0x2d/0x4e0 > rose_create+0x7b/0x330 > __sock_create+0x2dd/0x640 > __sys_socket+0xc7/0x270 > __x64_sys_socket+0x71/0x80 > do_syscall_64+0x43/0x90 > entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > Freed by task 152: > kasan_set_track+0x4c/0x70 > kasan_set_free_info+0x1f/0x40 > ____kasan_slab_free+0x124/0x190 > kfree+0xd3/0x270 > __sk_destruct+0x314/0x460 > rose_release+0x2fa/0x3b0 > sock_close+0xcb/0x230 > __fput+0x2d9/0x650 > task_work_run+0xd6/0x160 > exit_to_user_mode_loop+0xc7/0xd0 > exit_to_user_mode_prepare+0x4e/0x80 > syscall_exit_to_user_mode+0x20/0x40 > do_syscall_64+0x4f/0x90 > entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > This patch adds refcount of sock when we use functions > such as rose_start_heartbeat() and so on to start timer, > and decreases the refcount of sock when timer is finished > or deleted by functions such as rose_stop_heartbeat() > and so on. As a result, the UAF bugs could be mitigated. > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> > Tested-by: Duoming Zhou <duoming@zju.edu.cn> > --- > net/rose/rose_timer.c | 22 +++++++++++++--------- > 1 file changed, 13 insertions(+), 9 deletions(-) > > diff --git a/net/rose/rose_timer.c b/net/rose/rose_timer.c > index b3138fc2e55..18d1912520b 100644 > --- a/net/rose/rose_timer.c > +++ b/net/rose/rose_timer.c > @@ -36,7 +36,7 @@ void rose_start_heartbeat(struct sock *sk) > sk->sk_timer.function = rose_heartbeat_expiry; > sk->sk_timer.expires = jiffies + 5 * HZ; > > - add_timer(&sk->sk_timer); > + sk_reset_timer(sk, &sk->sk_timer, sk->sk_timer.expires); > } > > void rose_start_t1timer(struct sock *sk) > @@ -48,7 +48,7 @@ void rose_start_t1timer(struct sock *sk) > rose->timer.function = rose_timer_expiry; > rose->timer.expires = jiffies + rose->t1; > > - add_timer(&rose->timer); > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > } > > void rose_start_t2timer(struct sock *sk) > @@ -60,7 +60,7 @@ void rose_start_t2timer(struct sock *sk) > rose->timer.function = rose_timer_expiry; > rose->timer.expires = jiffies + rose->t2; > > - add_timer(&rose->timer); > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > } > > void rose_start_t3timer(struct sock *sk) > @@ -72,7 +72,7 @@ void rose_start_t3timer(struct sock *sk) > rose->timer.function = rose_timer_expiry; > rose->timer.expires = jiffies + rose->t3; > > - add_timer(&rose->timer); > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > } > > void rose_start_hbtimer(struct sock *sk) > @@ -84,7 +84,7 @@ void rose_start_hbtimer(struct sock *sk) > rose->timer.function = rose_timer_expiry; > rose->timer.expires = jiffies + rose->hb; > > - add_timer(&rose->timer); > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > } > > void rose_start_idletimer(struct sock *sk) > @@ -97,23 +97,23 @@ void rose_start_idletimer(struct sock *sk) > rose->idletimer.function = rose_idletimer_expiry; > rose->idletimer.expires = jiffies + rose->idle; > > - add_timer(&rose->idletimer); > + sk_reset_timer(sk, &rose->idletimer, rose->idletimer.expires); A few lines above there is still a 'del_timer(&rose->idletimer);' call which must be converted to sk_stop_timer(), otherwise there will be a possible sk reference leak. There are other del_timer(&rose->timer) that need conversion. Thanks Paolo
Hello, On Thu, 23 Jun 2022 11:13:41 +0200 Paolo Abeni wrote: > > There are UAF bugs in rose_heartbeat_expiry(), rose_timer_expiry() > > and rose_idletimer_expiry(). The root cause is that del_timer() > > could not stop the timer handler that is running and the refcount > > of sock is not managed properly. > > > > One of the UAF bugs is shown below: > > > > (thread 1) | (thread 2) > > | rose_bind > > | rose_connect > > | rose_start_heartbeat > > rose_release | (wait a time) > > case ROSE_STATE_0 | > > rose_destroy_socket | rose_heartbeat_expiry > > rose_stop_heartbeat | > > sock_put(sk) | ... > > sock_put(sk) // FREE | > > | bh_lock_sock(sk) // USE > > > > The sock is deallocated by sock_put() in rose_release() and > > then used by bh_lock_sock() in rose_heartbeat_expiry(). > > > > Although rose_destroy_socket() calls rose_stop_heartbeat(), > > it could not stop the timer that is running. > > > > The KASAN report triggered by POC is shown below: > > > > BUG: KASAN: use-after-free in _raw_spin_lock+0x5a/0x110 > > Write of size 4 at addr ffff88800ae59098 by task swapper/3/0 > > ... > > Call Trace: > > <IRQ> > > dump_stack_lvl+0xbf/0xee > > print_address_description+0x7b/0x440 > > print_report+0x101/0x230 > > ? irq_work_single+0xbb/0x140 > > ? _raw_spin_lock+0x5a/0x110 > > kasan_report+0xed/0x120 > > ? _raw_spin_lock+0x5a/0x110 > > kasan_check_range+0x2bd/0x2e0 > > _raw_spin_lock+0x5a/0x110 > > rose_heartbeat_expiry+0x39/0x370 > > ? rose_start_heartbeat+0xb0/0xb0 > > call_timer_fn+0x2d/0x1c0 > > ? rose_start_heartbeat+0xb0/0xb0 > > expire_timers+0x1f3/0x320 > > __run_timers+0x3ff/0x4d0 > > run_timer_softirq+0x41/0x80 > > __do_softirq+0x233/0x544 > > irq_exit_rcu+0x41/0xa0 > > sysvec_apic_timer_interrupt+0x8c/0xb0 > > </IRQ> > > <TASK> > > asm_sysvec_apic_timer_interrupt+0x1b/0x20 > > RIP: 0010:default_idle+0xb/0x10 > > RSP: 0018:ffffc9000012fea0 EFLAGS: 00000202 > > RAX: 000000000000bcae RBX: ffff888006660f00 RCX: 000000000000bcae > > RDX: 0000000000000001 RSI: ffffffff843a11c0 RDI: ffffffff843a1180 > > RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffed100da36d46 > > R10: dfffe9100da36d47 R11: ffffffff83cf0950 R12: 0000000000000000 > > R13: 1ffff11000ccc1e0 R14: ffffffff8542af28 R15: dffffc0000000000 > > ... > > Allocated by task 146: > > __kasan_kmalloc+0xc4/0xf0 > > sk_prot_alloc+0xdd/0x1a0 > > sk_alloc+0x2d/0x4e0 > > rose_create+0x7b/0x330 > > __sock_create+0x2dd/0x640 > > __sys_socket+0xc7/0x270 > > __x64_sys_socket+0x71/0x80 > > do_syscall_64+0x43/0x90 > > entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > > > Freed by task 152: > > kasan_set_track+0x4c/0x70 > > kasan_set_free_info+0x1f/0x40 > > ____kasan_slab_free+0x124/0x190 > > kfree+0xd3/0x270 > > __sk_destruct+0x314/0x460 > > rose_release+0x2fa/0x3b0 > > sock_close+0xcb/0x230 > > __fput+0x2d9/0x650 > > task_work_run+0xd6/0x160 > > exit_to_user_mode_loop+0xc7/0xd0 > > exit_to_user_mode_prepare+0x4e/0x80 > > syscall_exit_to_user_mode+0x20/0x40 > > do_syscall_64+0x4f/0x90 > > entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > > > This patch adds refcount of sock when we use functions > > such as rose_start_heartbeat() and so on to start timer, > > and decreases the refcount of sock when timer is finished > > or deleted by functions such as rose_stop_heartbeat() > > and so on. As a result, the UAF bugs could be mitigated. > > > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > > Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> > > Tested-by: Duoming Zhou <duoming@zju.edu.cn> > > --- > > net/rose/rose_timer.c | 22 +++++++++++++--------- > > 1 file changed, 13 insertions(+), 9 deletions(-) > > > > diff --git a/net/rose/rose_timer.c b/net/rose/rose_timer.c > > index b3138fc2e55..18d1912520b 100644 > > --- a/net/rose/rose_timer.c > > +++ b/net/rose/rose_timer.c > > @@ -36,7 +36,7 @@ void rose_start_heartbeat(struct sock *sk) > > sk->sk_timer.function = rose_heartbeat_expiry; > > sk->sk_timer.expires = jiffies + 5 * HZ; > > > > - add_timer(&sk->sk_timer); > > + sk_reset_timer(sk, &sk->sk_timer, sk->sk_timer.expires); > > } > > > > void rose_start_t1timer(struct sock *sk) > > @@ -48,7 +48,7 @@ void rose_start_t1timer(struct sock *sk) > > rose->timer.function = rose_timer_expiry; > > rose->timer.expires = jiffies + rose->t1; > > > > - add_timer(&rose->timer); > > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > > } > > > > void rose_start_t2timer(struct sock *sk) > > @@ -60,7 +60,7 @@ void rose_start_t2timer(struct sock *sk) > > rose->timer.function = rose_timer_expiry; > > rose->timer.expires = jiffies + rose->t2; > > > > - add_timer(&rose->timer); > > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > > } > > > > void rose_start_t3timer(struct sock *sk) > > @@ -72,7 +72,7 @@ void rose_start_t3timer(struct sock *sk) > > rose->timer.function = rose_timer_expiry; > > rose->timer.expires = jiffies + rose->t3; > > > > - add_timer(&rose->timer); > > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > > } > > > > void rose_start_hbtimer(struct sock *sk) > > @@ -84,7 +84,7 @@ void rose_start_hbtimer(struct sock *sk) > > rose->timer.function = rose_timer_expiry; > > rose->timer.expires = jiffies + rose->hb; > > > > - add_timer(&rose->timer); > > + sk_reset_timer(sk, &rose->timer, rose->timer.expires); > > } > > > > void rose_start_idletimer(struct sock *sk) > > @@ -97,23 +97,23 @@ void rose_start_idletimer(struct sock *sk) > > rose->idletimer.function = rose_idletimer_expiry; > > rose->idletimer.expires = jiffies + rose->idle; > > > > - add_timer(&rose->idletimer); > > + sk_reset_timer(sk, &rose->idletimer, rose->idletimer.expires); > > A few lines above there is still a 'del_timer(&rose->idletimer);' call > which must be converted to sk_stop_timer(), otherwise there will be a > possible sk reference leak. > > There are other del_timer(&rose->timer) that need conversion. Thank you for your time and suggestions! I will convert 'del_timer(&rose->idletimer);' and so on to sk_stop_timer(). Best regards, Duoming Zhou
diff --git a/net/rose/rose_timer.c b/net/rose/rose_timer.c index b3138fc2e55..18d1912520b 100644 --- a/net/rose/rose_timer.c +++ b/net/rose/rose_timer.c @@ -36,7 +36,7 @@ void rose_start_heartbeat(struct sock *sk) sk->sk_timer.function = rose_heartbeat_expiry; sk->sk_timer.expires = jiffies + 5 * HZ; - add_timer(&sk->sk_timer); + sk_reset_timer(sk, &sk->sk_timer, sk->sk_timer.expires); } void rose_start_t1timer(struct sock *sk) @@ -48,7 +48,7 @@ void rose_start_t1timer(struct sock *sk) rose->timer.function = rose_timer_expiry; rose->timer.expires = jiffies + rose->t1; - add_timer(&rose->timer); + sk_reset_timer(sk, &rose->timer, rose->timer.expires); } void rose_start_t2timer(struct sock *sk) @@ -60,7 +60,7 @@ void rose_start_t2timer(struct sock *sk) rose->timer.function = rose_timer_expiry; rose->timer.expires = jiffies + rose->t2; - add_timer(&rose->timer); + sk_reset_timer(sk, &rose->timer, rose->timer.expires); } void rose_start_t3timer(struct sock *sk) @@ -72,7 +72,7 @@ void rose_start_t3timer(struct sock *sk) rose->timer.function = rose_timer_expiry; rose->timer.expires = jiffies + rose->t3; - add_timer(&rose->timer); + sk_reset_timer(sk, &rose->timer, rose->timer.expires); } void rose_start_hbtimer(struct sock *sk) @@ -84,7 +84,7 @@ void rose_start_hbtimer(struct sock *sk) rose->timer.function = rose_timer_expiry; rose->timer.expires = jiffies + rose->hb; - add_timer(&rose->timer); + sk_reset_timer(sk, &rose->timer, rose->timer.expires); } void rose_start_idletimer(struct sock *sk) @@ -97,23 +97,23 @@ void rose_start_idletimer(struct sock *sk) rose->idletimer.function = rose_idletimer_expiry; rose->idletimer.expires = jiffies + rose->idle; - add_timer(&rose->idletimer); + sk_reset_timer(sk, &rose->idletimer, rose->idletimer.expires); } } void rose_stop_heartbeat(struct sock *sk) { - del_timer(&sk->sk_timer); + sk_stop_timer(sk, &sk->sk_timer); } void rose_stop_timer(struct sock *sk) { - del_timer(&rose_sk(sk)->timer); + sk_stop_timer(sk, &rose_sk(sk)->timer); } void rose_stop_idletimer(struct sock *sk) { - del_timer(&rose_sk(sk)->idletimer); + sk_stop_timer(sk, &rose_sk(sk)->idletimer); } static void rose_heartbeat_expiry(struct timer_list *t) @@ -130,6 +130,7 @@ static void rose_heartbeat_expiry(struct timer_list *t) (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { bh_unlock_sock(sk); rose_destroy_socket(sk); + sock_put(sk); return; } break; @@ -152,6 +153,7 @@ static void rose_heartbeat_expiry(struct timer_list *t) rose_start_heartbeat(sk); bh_unlock_sock(sk); + sock_put(sk); } static void rose_timer_expiry(struct timer_list *t) @@ -181,6 +183,7 @@ static void rose_timer_expiry(struct timer_list *t) break; } bh_unlock_sock(sk); + sock_put(sk); } static void rose_idletimer_expiry(struct timer_list *t) @@ -205,4 +208,5 @@ static void rose_idletimer_expiry(struct timer_list *t) sock_set_flag(sk, SOCK_DEAD); } bh_unlock_sock(sk); + sock_put(sk); }