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* WARNING in cma_exit_net
@ 2019-04-01 17:36 syzbot
  2019-04-01 17:45 ` Jason Gunthorpe
  0 siblings, 1 reply; 5+ messages in thread
From: syzbot @ 2019-04-01 17:36 UTC (permalink / raw)
  To: danielj, danitg, dledford, jgg, leon, linux-kernel, linux-rdma,
	parav, swise, syzkaller-bugs

Hello,

syzbot found the following crash on:

HEAD commit:    e3ecb83e Add linux-next specific files for 20190401
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=13bc36cd200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=db6c9f2bfeb91a99
dashboard link: https://syzkaller.appspot.com/bug?extid=2e3e485d5697ea610460
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+2e3e485d5697ea610460@syzkaller.appspotmail.com

WARNING: CPU: 1 PID: 7 at drivers/infiniband/core/cma.c:4674  
cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.1.0-rc2-next-20190401 #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x172/0x1f0 lib/dump_stack.c:113
  panic+0x2cb/0x65c kernel/panic.c:214
  __warn.cold+0x20/0x45 kernel/panic.c:571
  report_bug+0x263/0x2b0 lib/bug.c:186
  fixup_bug arch/x86/kernel/traps.c:179 [inline]
  fixup_bug arch/x86/kernel/traps.c:174 [inline]
  do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
  do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
  invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
Code: 00 48 c7 c7 c0 4e ea 87 c6 05 89 86 4a 04 01 e8 ba cc 46 fc e9 c8 fd  
ff ff e8 25 6c 5f fc 0f 0b e9 d7 fe ff ff e8 19 6c 5f fc <0f> 0b e8 12 6c  
5f fc 48 8d 65 e8 5b 41 5c 41 5d 5d c3 e8 02 6c 5f
RSP: 0000:ffff8880aa267bf0 EFLAGS: 00010293
RAX: ffff8880aa2581c0 RBX: ffff8880a538d500 RCX: 1ffff1101544b146
RDX: 0000000000000000 RSI: ffffffff85111537 RDI: ffff8880a538d618
RBP: ffff8880aa267c08 R08: ffff8880aa2581c0 R09: 0000000000000004
R10: ffffed1015d25bcf R11: ffff8880ae92de7b R12: 0000000000000001
R13: ffff8880a90e84c0 R14: ffffffff891e29f8 R15: dffffc0000000000
  ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153
  cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552
  process_one_work+0x98e/0x1790 kernel/workqueue.c:2270
  worker_thread+0x98/0xe40 kernel/workqueue.c:2416
  kthread+0x357/0x430 kernel/kthread.c:254
  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: WARNING in cma_exit_net
  2019-04-01 17:36 WARNING in cma_exit_net syzbot
@ 2019-04-01 17:45 ` Jason Gunthorpe
  2019-04-01 18:29   ` Leon Romanovsky
  0 siblings, 1 reply; 5+ messages in thread
From: Jason Gunthorpe @ 2019-04-01 17:45 UTC (permalink / raw)
  To: syzbot, Matthew Wilcox
  Cc: danielj, danitg, dledford, leon, linux-kernel, linux-rdma, parav,
	swise, syzkaller-bugs

On Mon, Apr 01, 2019 at 10:36:05AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    e3ecb83e Add linux-next specific files for 20190401
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=13bc36cd200000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=db6c9f2bfeb91a99
> dashboard link: https://syzkaller.appspot.com/bug?extid=2e3e485d5697ea610460
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> 
> Unfortunately, I don't have any reproducer for this crash yet.
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+2e3e485d5697ea610460@syzkaller.appspotmail.com
> 
> WARNING: CPU: 1 PID: 7 at drivers/infiniband/core/cma.c:4674
> cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
> Kernel panic - not syncing: panic_on_warn set ...

Matt: This is why the WARN_ON(!xa_empty()) is so valuable. Magically
syzkaller can find something in this code is buggy.

Mellanox is also showing a different testing failure over the weekend
(use after free or something) from your 'cma: Convert portspace IDRs
to XArray'

If you seem something obvious wrong in that patch please speak
up.. Below is what I applied.

Thanks,
Jason

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 68c997be242930..a8b9c66c85252b 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -39,7 +39,7 @@
 #include <linux/mutex.h>
 #include <linux/random.h>
 #include <linux/igmp.h>
-#include <linux/idr.h>
+#include <linux/xarray.h>
 #include <linux/inetdevice.h>
 #include <linux/slab.h>
 #include <linux/module.h>
@@ -191,10 +191,10 @@ static struct workqueue_struct *cma_wq;
 static unsigned int cma_pernet_id;
 
 struct cma_pernet {
-	struct idr tcp_ps;
-	struct idr udp_ps;
-	struct idr ipoib_ps;
-	struct idr ib_ps;
+	struct xarray tcp_ps;
+	struct xarray udp_ps;
+	struct xarray ipoib_ps;
+	struct xarray ib_ps;
 };
 
 static struct cma_pernet *cma_pernet(struct net *net)
@@ -202,7 +202,8 @@ static struct cma_pernet *cma_pernet(struct net *net)
 	return net_generic(net, cma_pernet_id);
 }
 
-static struct idr *cma_pernet_idr(struct net *net, enum rdma_ucm_port_space ps)
+static
+struct xarray *cma_pernet_xa(struct net *net, enum rdma_ucm_port_space ps)
 {
 	struct cma_pernet *pernet = cma_pernet(net);
 
@@ -247,25 +248,25 @@ struct class_port_info_context {
 static int cma_ps_alloc(struct net *net, enum rdma_ucm_port_space ps,
 			struct rdma_bind_list *bind_list, int snum)
 {
-	struct idr *idr = cma_pernet_idr(net, ps);
+	struct xarray *xa = cma_pernet_xa(net, ps);
 
-	return idr_alloc(idr, bind_list, snum, snum + 1, GFP_KERNEL);
+	return xa_insert(xa, snum, bind_list, GFP_KERNEL);
 }
 
 static struct rdma_bind_list *cma_ps_find(struct net *net,
 					  enum rdma_ucm_port_space ps, int snum)
 {
-	struct idr *idr = cma_pernet_idr(net, ps);
+	struct xarray *xa = cma_pernet_xa(net, ps);
 
-	return idr_find(idr, snum);
+	return xa_load(xa, snum);
 }
 
 static void cma_ps_remove(struct net *net, enum rdma_ucm_port_space ps,
 			  int snum)
 {
-	struct idr *idr = cma_pernet_idr(net, ps);
+	struct xarray *xa = cma_pernet_xa(net, ps);
 
-	idr_remove(idr, snum);
+	xa_erase(xa, snum);
 }
 
 enum {
@@ -4655,10 +4656,10 @@ static int cma_init_net(struct net *net)
 {
 	struct cma_pernet *pernet = cma_pernet(net);
 
-	idr_init(&pernet->tcp_ps);
-	idr_init(&pernet->udp_ps);
-	idr_init(&pernet->ipoib_ps);
-	idr_init(&pernet->ib_ps);
+	xa_init(&pernet->tcp_ps);
+	xa_init(&pernet->udp_ps);
+	xa_init(&pernet->ipoib_ps);
+	xa_init(&pernet->ib_ps);
 
 	return 0;
 }
@@ -4667,10 +4668,10 @@ static void cma_exit_net(struct net *net)
 {
 	struct cma_pernet *pernet = cma_pernet(net);
 
-	idr_destroy(&pernet->tcp_ps);
-	idr_destroy(&pernet->udp_ps);
-	idr_destroy(&pernet->ipoib_ps);
-	idr_destroy(&pernet->ib_ps);
+	WARN_ON(!xa_empty(&pernet->tcp_ps));
+	WARN_ON(!xa_empty(&pernet->udp_ps));
+	WARN_ON(!xa_empty(&pernet->ipoib_ps));
+	WARN_ON(!xa_empty(&pernet->ib_ps));
 }
 
 static struct pernet_operations cma_pernet_operations = {


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: WARNING in cma_exit_net
  2019-04-01 17:45 ` Jason Gunthorpe
@ 2019-04-01 18:29   ` Leon Romanovsky
  2019-04-02 23:39     ` Bart Van Assche
  0 siblings, 1 reply; 5+ messages in thread
From: Leon Romanovsky @ 2019-04-01 18:29 UTC (permalink / raw)
  To: Jason Gunthorpe
  Cc: syzbot, Matthew Wilcox, danielj, danitg, dledford, linux-kernel,
	linux-rdma, parav, swise, syzkaller-bugs

[-- Attachment #1: Type: text/plain, Size: 9344 bytes --]

On Mon, Apr 01, 2019 at 02:45:54PM -0300, Jason Gunthorpe wrote:
> On Mon, Apr 01, 2019 at 10:36:05AM -0700, syzbot wrote:
> > Hello,
> >
> > syzbot found the following crash on:
> >
> > HEAD commit:    e3ecb83e Add linux-next specific files for 20190401
> > git tree:       linux-next
> > console output: https://syzkaller.appspot.com/x/log.txt?x=13bc36cd200000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=db6c9f2bfeb91a99
> > dashboard link: https://syzkaller.appspot.com/bug?extid=2e3e485d5697ea610460
> > compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> >
> > Unfortunately, I don't have any reproducer for this crash yet.
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: syzbot+2e3e485d5697ea610460@syzkaller.appspotmail.com
> >
> > WARNING: CPU: 1 PID: 7 at drivers/infiniband/core/cma.c:4674
> > cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
> > Kernel panic - not syncing: panic_on_warn set ...
>
> Matt: This is why the WARN_ON(!xa_empty()) is so valuable. Magically
> syzkaller can find something in this code is buggy.
>
> Mellanox is also showing a different testing failure over the weekend
> (use after free or something) from your 'cma: Convert portspace IDRs
> to XArray'

This is what I see in my environment.

[   72.725596]
==================================================================
[   72.726017] BUG: KASAN: use-after-free in cma_check_port+0x86a/0xa20 [rdma_cm]
[   72.726263] Read of size 8 at addr ffff888069fde998 by task ucmatose/387
[   72.726460]
[   72.726550] CPU: 3 PID: 387 Comm: ucmatose Not tainted 5.1.0-rc2+ #253
[   72.726751] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
[   72.727119] Call Trace:
[   72.727210]  dump_stack+0x7c/0xc0
[   72.727342]  print_address_description+0x6c/0x23c
[   72.727505]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
[   72.727666]  kasan_report.cold.3+0x1c/0x35
[   72.727805]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
[   72.727977]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
[   72.728138]  cma_check_port+0x86a/0xa20 [rdma_cm]
[   72.728306]  rdma_bind_addr+0x11bc/0x1b00 [rdma_cm]
[   72.728465]  ? find_held_lock+0x33/0x1c0
[   72.728597]  ? cma_ndev_work_handler+0x180/0x180 [rdma_cm]
[   72.728756]  ? wait_for_completion+0x3d0/0x3d0
[   72.728928]  ucma_bind+0x120/0x160 [rdma_ucm]
[   72.729089]  ? ucma_resolve_addr+0x1a0/0x1a0 [rdma_ucm]
[   72.729256]  ucma_write+0x1f8/0x2b0 [rdma_ucm]
[   72.729409]  ? ucma_open+0x260/0x260 [rdma_ucm]
[   72.729571]  vfs_write+0x157/0x460
[   72.729688]  ksys_write+0xb8/0x170
[   72.729828]  ? __ia32_sys_read+0xb0/0xb0
[   72.729954]  ? trace_hardirqs_off_caller+0x5b/0x160
[   72.730107]  ? do_syscall_64+0x18/0x3c0
[   72.730243]  do_syscall_64+0x95/0x3c0
[   72.730363]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   72.730508] RIP: 0033:0x7f6f1758fff8
[   72.730624] Code: 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00
00 f3 0f 1e fa 48 8d 05 25 77 0d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f
05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 49 89 d4
 55
 [   72.731146] RSP: 002b:00007fff99f99088 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 [   72.731365] RAX: ffffffffffffffda RBX: 00007fff99f99090 RCX: 00007f6f1758fff8
 [   72.731579] RDX: 0000000000000090 RSI: 00007fff99f99090 RDI: 0000000000000003
 [   72.731814] RBP: 0000564942bd8ec0 R08: 0000564942bd9180 R09: 0000000000000000
 [   72.732043] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
 [   72.732262] R13: 0000000000000001 R14: 0000000000000000 R15: 00005649413cc470
 [   72.732494]
 [   72.732572] Allocated by task 381:
 [   72.732692]  __kasan_kmalloc.constprop.5+0xc1/0xd0
 [   72.732857]  cma_alloc_port+0x4d/0x160 [rdma_cm]
 [   72.733006]  rdma_bind_addr+0x14e7/0x1b00 [rdma_cm]
 [   72.733153]  ucma_bind+0x120/0x160 [rdma_ucm]
 [   72.733299]  ucma_write+0x1f8/0x2b0 [rdma_ucm]
 [   72.733452]  vfs_write+0x157/0x460
 [   72.733569]  ksys_write+0xb8/0x170
 [   72.733675]  do_syscall_64+0x95/0x3c0
 [   72.733800]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [   72.733956]
 [   72.734029] Freed by task 381:
 [   72.734133]  __kasan_slab_free+0x12e/0x180
 [   72.734284]  kfree+0xed/0x290
 [   72.734399]  rdma_destroy_id+0x6b6/0x9e0 [rdma_cm]
 [   72.734559]  ucma_close+0x110/0x300 [rdma_ucm]
 [   72.734701]  __fput+0x25a/0x740
 [   72.734832]  task_work_run+0x10e/0x190
 [   72.734959]  do_exit+0x85e/0x29e0
 [   72.735071]  do_group_exit+0xf0/0x2e0
 [   72.735182]  get_signal+0x2e0/0x17e0
 [   72.735304]  do_signal+0x94/0x1570
 [   72.735424]  exit_to_usermode_loop+0xfa/0x130
 [   72.735612]  do_syscall_64+0x327/0x3c0
 [   72.735756]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [   72.735941]
 [   72.736033] The buggy address belongs to the object at ffff888069fde990
 [   72.736033]  which belongs to the cache kmalloc-32 of size 32
 [   72.736414] The buggy address is located 8 bytes inside of
 [   72.736414]  32-byte region [ffff888069fde990, ffff888069fde9b0)
 [   72.736777] The buggy address belongs to the page:
 [   72.736940] page:ffffea0001a7f780 count:1 mapcount:0 mapping:ffff88806bc03980 index:0x0
 [   72.737171] flags: 0x4000000000000200(slab)
 [   72.737295] raw: 4000000000000200 dead000000000100 dead000000000200 ffff88806bc03980
 [   72.737525] raw: 0000000000000000 0000000000550055 00000001ffffffff 0000000000000000
 [   72.737786] page dumped because: kasan: bad access detected
 [   72.737948]
 [   72.738019] Memory state around the buggy address:
 [   72.738164]  ffff888069fde880: fb fb fc fc fb fb fb fb fc fc fb fb  fb fb fc fc
 [   72.738396]  ffff888069fde900: fb fb fb fb fc fc fb fb fb fb fc fc  fb fb fb fb
 [   72.738627] >ffff888069fde980: fc fc fb fb fb fb fc fc fb fb fb fb  fc fc fb fb
 [   72.738869]                             ^
 [   72.738999]  ffff888069fdea00: fb fb fc fc fb fb fb fb fc fc fb fb  fb fb fc fc
 [   72.739213]  ffff888069fdea80: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
 [   72.739431]
 ==================================================================
 [   72.739667] Disabling lock debugging due to kernel taint




>
> If you seem something obvious wrong in that patch please speak
> up.. Below is what I applied.
>
> Thanks,
> Jason
>
> diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
> index 68c997be242930..a8b9c66c85252b 100644
> --- a/drivers/infiniband/core/cma.c
> +++ b/drivers/infiniband/core/cma.c
> @@ -39,7 +39,7 @@
>  #include <linux/mutex.h>
>  #include <linux/random.h>
>  #include <linux/igmp.h>
> -#include <linux/idr.h>
> +#include <linux/xarray.h>
>  #include <linux/inetdevice.h>
>  #include <linux/slab.h>
>  #include <linux/module.h>
> @@ -191,10 +191,10 @@ static struct workqueue_struct *cma_wq;
>  static unsigned int cma_pernet_id;
>
>  struct cma_pernet {
> -	struct idr tcp_ps;
> -	struct idr udp_ps;
> -	struct idr ipoib_ps;
> -	struct idr ib_ps;
> +	struct xarray tcp_ps;
> +	struct xarray udp_ps;
> +	struct xarray ipoib_ps;
> +	struct xarray ib_ps;
>  };
>
>  static struct cma_pernet *cma_pernet(struct net *net)
> @@ -202,7 +202,8 @@ static struct cma_pernet *cma_pernet(struct net *net)
>  	return net_generic(net, cma_pernet_id);
>  }
>
> -static struct idr *cma_pernet_idr(struct net *net, enum rdma_ucm_port_space ps)
> +static
> +struct xarray *cma_pernet_xa(struct net *net, enum rdma_ucm_port_space ps)
>  {
>  	struct cma_pernet *pernet = cma_pernet(net);
>
> @@ -247,25 +248,25 @@ struct class_port_info_context {
>  static int cma_ps_alloc(struct net *net, enum rdma_ucm_port_space ps,
>  			struct rdma_bind_list *bind_list, int snum)
>  {
> -	struct idr *idr = cma_pernet_idr(net, ps);
> +	struct xarray *xa = cma_pernet_xa(net, ps);
>
> -	return idr_alloc(idr, bind_list, snum, snum + 1, GFP_KERNEL);
> +	return xa_insert(xa, snum, bind_list, GFP_KERNEL);
>  }
>
>  static struct rdma_bind_list *cma_ps_find(struct net *net,
>  					  enum rdma_ucm_port_space ps, int snum)
>  {
> -	struct idr *idr = cma_pernet_idr(net, ps);
> +	struct xarray *xa = cma_pernet_xa(net, ps);
>
> -	return idr_find(idr, snum);
> +	return xa_load(xa, snum);
>  }
>
>  static void cma_ps_remove(struct net *net, enum rdma_ucm_port_space ps,
>  			  int snum)
>  {
> -	struct idr *idr = cma_pernet_idr(net, ps);
> +	struct xarray *xa = cma_pernet_xa(net, ps);
>
> -	idr_remove(idr, snum);
> +	xa_erase(xa, snum);
>  }
>
>  enum {
> @@ -4655,10 +4656,10 @@ static int cma_init_net(struct net *net)
>  {
>  	struct cma_pernet *pernet = cma_pernet(net);
>
> -	idr_init(&pernet->tcp_ps);
> -	idr_init(&pernet->udp_ps);
> -	idr_init(&pernet->ipoib_ps);
> -	idr_init(&pernet->ib_ps);
> +	xa_init(&pernet->tcp_ps);
> +	xa_init(&pernet->udp_ps);
> +	xa_init(&pernet->ipoib_ps);
> +	xa_init(&pernet->ib_ps);
>
>  	return 0;
>  }
> @@ -4667,10 +4668,10 @@ static void cma_exit_net(struct net *net)
>  {
>  	struct cma_pernet *pernet = cma_pernet(net);
>
> -	idr_destroy(&pernet->tcp_ps);
> -	idr_destroy(&pernet->udp_ps);
> -	idr_destroy(&pernet->ipoib_ps);
> -	idr_destroy(&pernet->ib_ps);
> +	WARN_ON(!xa_empty(&pernet->tcp_ps));
> +	WARN_ON(!xa_empty(&pernet->udp_ps));
> +	WARN_ON(!xa_empty(&pernet->ipoib_ps));
> +	WARN_ON(!xa_empty(&pernet->ib_ps));
>  }
>
>  static struct pernet_operations cma_pernet_operations = {
>

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^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: WARNING in cma_exit_net
  2019-04-01 18:29   ` Leon Romanovsky
@ 2019-04-02 23:39     ` Bart Van Assche
  2019-04-03  5:11       ` Leon Romanovsky
  0 siblings, 1 reply; 5+ messages in thread
From: Bart Van Assche @ 2019-04-02 23:39 UTC (permalink / raw)
  To: Leon Romanovsky, Jason Gunthorpe
  Cc: syzbot, Matthew Wilcox, danielj, danitg, dledford, linux-kernel,
	linux-rdma, parav, swise, syzkaller-bugs

On Mon, 2019-04-01 at 21:29 +0300, Leon Romanovsky wrote:
> On Mon, Apr 01, 2019 at 02:45:54PM -0300, Jason Gunthorpe wrote:
> > On Mon, Apr 01, 2019 at 10:36:05AM -0700, syzbot wrote:
> > > Hello,
> > > 
> > > syzbot found the following crash on:
> > > 
> > > HEAD commit:    e3ecb83e Add linux-next specific files for 20190401
> > > git tree:       linux-next
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=13bc36cd200000
> > > kernel config:  https://syzkaller.appspot.com/x/.config?x=db6c9f2bfeb91a99
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=2e3e485d5697ea610460
> > > compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> > > 
> > > Unfortunately, I don't have any reproducer for this crash yet.
> > > 
> > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > Reported-by: syzbot+2e3e485d5697ea610460@syzkaller.appspotmail.com
> > > 
> > > WARNING: CPU: 1 PID: 7 at drivers/infiniband/core/cma.c:4674
> > > cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
> > > Kernel panic - not syncing: panic_on_warn set ...
> > 
> > Matt: This is why the WARN_ON(!xa_empty()) is so valuable. Magically
> > syzkaller can find something in this code is buggy.
> > 
> > Mellanox is also showing a different testing failure over the weekend
> > (use after free or something) from your 'cma: Convert portspace IDRs
> > to XArray'
> 
> This is what I see in my environment.
> 
> [   72.725596]
> ==================================================================
> [   72.726017] BUG: KASAN: use-after-free in cma_check_port+0x86a/0xa20 [rdma_cm]
> [   72.726263] Read of size 8 at addr ffff888069fde998 by task ucmatose/387
> [   72.726460]
> [   72.726550] CPU: 3 PID: 387 Comm: ucmatose Not tainted 5.1.0-rc2+ #253
> [   72.726751] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
> rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
> [   72.727119] Call Trace:
> [   72.727210]  dump_stack+0x7c/0xc0
> [   72.727342]  print_address_description+0x6c/0x23c
> [   72.727505]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
> [   72.727666]  kasan_report.cold.3+0x1c/0x35
> [   72.727805]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
> [   72.727977]  ? cma_check_port+0x86a/0xa20 [rdma_cm]
> [   72.728138]  cma_check_port+0x86a/0xa20 [rdma_cm]
> [   72.728306]  rdma_bind_addr+0x11bc/0x1b00 [rdma_cm]
> [   72.728465]  ? find_held_lock+0x33/0x1c0
> [   72.728597]  ? cma_ndev_work_handler+0x180/0x180 [rdma_cm]
> [   72.728756]  ? wait_for_completion+0x3d0/0x3d0
> [   72.728928]  ucma_bind+0x120/0x160 [rdma_ucm]
> [   72.729089]  ? ucma_resolve_addr+0x1a0/0x1a0 [rdma_ucm]
> [   72.729256]  ucma_write+0x1f8/0x2b0 [rdma_ucm]
> [   72.729409]  ? ucma_open+0x260/0x260 [rdma_ucm]
> [   72.729571]  vfs_write+0x157/0x460
> [   72.729688]  ksys_write+0xb8/0x170
> [   72.729828]  ? __ia32_sys_read+0xb0/0xb0
> [   72.729954]  ? trace_hardirqs_off_caller+0x5b/0x160
> [   72.730107]  ? do_syscall_64+0x18/0x3c0
> [   72.730243]  do_syscall_64+0x95/0x3c0
> [   72.730363]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [   72.730508] RIP: 0033:0x7f6f1758fff8
> [   72.730624] Code: 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00
> 00 f3 0f 1e fa 48 8d 05 25 77 0d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f
> 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 49 89 d4
>  55
>  [   72.731146] RSP: 002b:00007fff99f99088 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
>  [   72.731365] RAX: ffffffffffffffda RBX: 00007fff99f99090 RCX: 00007f6f1758fff8
>  [   72.731579] RDX: 0000000000000090 RSI: 00007fff99f99090 RDI: 0000000000000003
>  [   72.731814] RBP: 0000564942bd8ec0 R08: 0000564942bd9180 R09: 0000000000000000
>  [   72.732043] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
>  [   72.732262] R13: 0000000000000001 R14: 0000000000000000 R15: 00005649413cc470
>  [   72.732494]
>  [   72.732572] Allocated by task 381:
>  [   72.732692]  __kasan_kmalloc.constprop.5+0xc1/0xd0
>  [   72.732857]  cma_alloc_port+0x4d/0x160 [rdma_cm]
>  [   72.733006]  rdma_bind_addr+0x14e7/0x1b00 [rdma_cm]
>  [   72.733153]  ucma_bind+0x120/0x160 [rdma_ucm]
>  [   72.733299]  ucma_write+0x1f8/0x2b0 [rdma_ucm]
>  [   72.733452]  vfs_write+0x157/0x460
>  [   72.733569]  ksys_write+0xb8/0x170
>  [   72.733675]  do_syscall_64+0x95/0x3c0
>  [   72.733800]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>  [   72.733956]
>  [   72.734029] Freed by task 381:
>  [   72.734133]  __kasan_slab_free+0x12e/0x180
>  [   72.734284]  kfree+0xed/0x290
>  [   72.734399]  rdma_destroy_id+0x6b6/0x9e0 [rdma_cm]
>  [   72.734559]  ucma_close+0x110/0x300 [rdma_ucm]
>  [   72.734701]  __fput+0x25a/0x740
>  [   72.734832]  task_work_run+0x10e/0x190
>  [   72.734959]  do_exit+0x85e/0x29e0
>  [   72.735071]  do_group_exit+0xf0/0x2e0
>  [   72.735182]  get_signal+0x2e0/0x17e0
>  [   72.735304]  do_signal+0x94/0x1570
>  [   72.735424]  exit_to_usermode_loop+0xfa/0x130
>  [   72.735612]  do_syscall_64+0x327/0x3c0
>  [   72.735756]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>  [   72.735941]
>  [   72.736033] The buggy address belongs to the object at ffff888069fde990
>  [   72.736033]  which belongs to the cache kmalloc-32 of size 32
>  [   72.736414] The buggy address is located 8 bytes inside of
>  [   72.736414]  32-byte region [ffff888069fde990, ffff888069fde9b0)
>  [   72.736777] The buggy address belongs to the page:
>  [   72.736940] page:ffffea0001a7f780 count:1 mapcount:0 mapping:ffff88806bc03980 index:0x0
>  [   72.737171] flags: 0x4000000000000200(slab)
>  [   72.737295] raw: 4000000000000200 dead000000000100 dead000000000200 ffff88806bc03980
>  [   72.737525] raw: 0000000000000000 0000000000550055 00000001ffffffff 0000000000000000
>  [   72.737786] page dumped because: kasan: bad access detected
>  [   72.737948]
>  [   72.738019] Memory state around the buggy address:
>  [   72.738164]  ffff888069fde880: fb fb fc fc fb fb fb fb fc fc fb fb  fb fb fc fc
>  [   72.738396]  ffff888069fde900: fb fb fb fb fc fc fb fb fb fb fc fc  fb fb fb fb
>  [   72.738627] >ffff888069fde980: fc fc fb fb fb fb fc fc fb fb fb fb  fc fc fb fb
>  [   72.738869]                             ^
>  [   72.738999]  ffff888069fdea00: fb fb fc fc fb fb fb fb fc fc fb fb  fb fb fc fc
>  [   72.739213]  ffff888069fdea80: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
>  [   72.739431]
>  ==================================================================
>  [   72.739667] Disabling lock debugging due to kernel taint

This is what I encountered while running blktests:

nvmet: adding nsid 1 to subsystem nvme-test
==================================================================
BUG: KASAN: use-after-free in cma_check_port+0x28/0x400 [rdma_cm]
Read of size 8 at addr ffff8880ba96f818 by task ln/10510

CPU: 5 PID: 10510 Comm: ln Not tainted 5.1.0-rc3-dbg+ #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
 dump_stack+0x86/0xca
 print_address_description+0x71/0x239
 ? cma_check_port+0x28/0x400 [rdma_cm]
 kasan_report.cold.3+0x1b/0x3e
 ? cma_check_port+0x28/0x400 [rdma_cm]
 __asan_load8+0x54/0x90
 cma_check_port+0x28/0x400 [rdma_cm]
 rdma_bind_addr+0xc13/0xe80 [rdma_cm]
 ? cma_ndev_work_handler+0xf0/0xf0 [rdma_cm]
 ? lockdep_hardirqs_on+0x185/0x260
 ? _raw_spin_unlock_irqrestore+0x57/0x70
 ? trace_hardirqs_on+0x24/0x130
 ? preempt_count_sub+0x18/0xd0
 ? _raw_spin_unlock_irqrestore+0x42/0x70
 nvmet_rdma_add_port+0x143/0x1a0 [nvmet_rdma]
 ? nvmet_rdma_remove_port+0x40/0x40 [nvmet_rdma]
 nvmet_enable_port+0x85/0x180 [nvmet]
 nvmet_port_subsys_allow_link+0x1bc/0x1e0 [nvmet]
 ? do_raw_spin_unlock+0xa8/0x140
 configfs_symlink+0x2b6/0x650
 ? configfs_get_link+0x3e0/0x3e0
 ? inode_permission+0x69/0x200
 vfs_symlink+0x163/0x230
 do_symlinkat+0xeb/0x160
 ? __ia32_sys_unlink+0x40/0x40
 ? do_syscall_64+0x19/0x210
 ? entry_SYSCALL_64_after_hwframe+0x49/0xbe
 __x64_sys_symlinkat+0x43/0x50
 do_syscall_64+0x71/0x210
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f35b984d9e7
Code: 73 01 c3 48 8b 0d a9 84 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 79 84 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffcc3a88af8 EFLAGS: 00000246 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f35b984d9e7
RDX: 000055c1855f82b0 RSI: 00000000ffffff9c RDI: 00007ffcc3a8a7a6
RBP: 00000000ffffff9c R08: 000055c1855f8010 R09: 0000000000000000
R10: fffffffffffff000 R11: 0000000000000246 R12: 000055c1855f82b0
R13: 00007ffcc3a8a7a6 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 10270:
 save_stack+0x43/0xd0
 __kasan_kmalloc.constprop.9+0xc7/0xd0
 kasan_kmalloc+0x9/0x10
 kmem_cache_alloc_trace+0x143/0x350
 cma_alloc_port+0x3d/0xf0 [rdma_cm]
 rdma_bind_addr+0xdf9/0xe80 [rdma_cm]
 nvmet_clear_ctrl+0x43/0x70 [nvmet]
 rxe_opcode+0x15f5/0xfffffffffffef380 [rdma_rxe]
 rxe_wr_opcode_info+0xa4c/0xfffffffffffeb360 [rdma_rxe]
 configfs_symlink+0x2b6/0x650
 vfs_symlink+0x163/0x230
 do_symlinkat+0xeb/0x160
 __x64_sys_symlinkat+0x43/0x50
 do_syscall_64+0x71/0x210
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 10340:
 save_stack+0x43/0xd0
 __kasan_slab_free+0x139/0x190
 kasan_slab_free+0xe/0x10
 kfree+0x103/0x320
 rdma_destroy_id+0x42c/0x460 [rdma_cm]
 nvmet_ctrl_fatal_error+0x31/0x80 [nvmet]
 rxe_opcode+0x175d/0xfffffffffffef380 [rdma_rxe]
 rxe_wr_opcode_info+0x644/0xfffffffffffeb360 [rdma_rxe]
 configfs_unlink+0x216/0x350
 vfs_unlink+0x171/0x260
 do_unlinkat+0x347/0x490
 __x64_sys_unlinkat+0x60/0x90
 do_syscall_64+0x71/0x210
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880ba96f810
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 8 bytes inside of
 32-byte region [ffff8880ba96f810, ffff8880ba96f830)
The buggy address belongs to the page:
page:ffffea0002ea5bc0 count:1 mapcount:0 mapping:ffff88811b003800 index:0x0
flags: 0x1fff000000000200(slab)
raw: 1fff000000000200 ffffea0004319200 0000000900000009 ffff88811b003800
raw: 0000000000000000 0000000000550055 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880ba96f700: fb fb fc fc fb fb fb fb fc fc fb fb fb fb fc fc
 ffff8880ba96f780: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
>ffff8880ba96f800: fc fc fb fb fb fb fc fc fb fb fb fb fc fc fb fb
                            ^
 ffff8880ba96f880: fb fb fc fc fb fb fb fb fc fc fb fb fb fb fc fc
 ffff8880ba96f900: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
==================================================================
Disabling lock debugging due to kernel taint
nvmet_rdma: enabling port 1 (192.168.122.49:7777)


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: WARNING in cma_exit_net
  2019-04-02 23:39     ` Bart Van Assche
@ 2019-04-03  5:11       ` Leon Romanovsky
  0 siblings, 0 replies; 5+ messages in thread
From: Leon Romanovsky @ 2019-04-03  5:11 UTC (permalink / raw)
  To: Bart Van Assche
  Cc: Jason Gunthorpe, syzbot, Matthew Wilcox, danielj, danitg,
	dledford, linux-kernel, linux-rdma, parav, swise, syzkaller-bugs

[-- Attachment #1: Type: text/plain, Size: 1657 bytes --]

On Tue, Apr 02, 2019 at 04:39:12PM -0700, Bart Van Assche wrote:
> On Mon, 2019-04-01 at 21:29 +0300, Leon Romanovsky wrote:
> > On Mon, Apr 01, 2019 at 02:45:54PM -0300, Jason Gunthorpe wrote:
> > > On Mon, Apr 01, 2019 at 10:36:05AM -0700, syzbot wrote:
> > > > Hello,
> > > >
> > > > syzbot found the following crash on:
> > > >
> > > > HEAD commit:    e3ecb83e Add linux-next specific files for 20190401
> > > > git tree:       linux-next
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=13bc36cd200000
> > > > kernel config:  https://syzkaller.appspot.com/x/.config?x=db6c9f2bfeb91a99
> > > > dashboard link: https://syzkaller.appspot.com/bug?extid=2e3e485d5697ea610460
> > > > compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> > > >
> > > > Unfortunately, I don't have any reproducer for this crash yet.
> > > >
> > > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > > Reported-by: syzbot+2e3e485d5697ea610460@syzkaller.appspotmail.com
> > > >
> > > > WARNING: CPU: 1 PID: 7 at drivers/infiniband/core/cma.c:4674
> > > > cma_exit_net+0x327/0x390 drivers/infiniband/core/cma.c:4674
> > > > Kernel panic - not syncing: panic_on_warn set ...
> > >
> > > Matt: This is why the WARN_ON(!xa_empty()) is so valuable. Magically
> > > syzkaller can find something in this code is buggy.
> > >
> > > Mellanox is also showing a different testing failure over the weekend
> > > (use after free or something) from your 'cma: Convert portspace IDRs
> > > to XArray'
> >
> > This is what I see in my environment.

Bart,

This patch [1] will fix it.

Thanks

[1] https://patchwork.kernel.org/patch/10881501/

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^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2019-04-03  5:11 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-04-01 17:36 WARNING in cma_exit_net syzbot
2019-04-01 17:45 ` Jason Gunthorpe
2019-04-01 18:29   ` Leon Romanovsky
2019-04-02 23:39     ` Bart Van Assche
2019-04-03  5:11       ` Leon Romanovsky

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