* [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg()
@ 2011-05-27 6:00 Namhyung Kim
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Namhyung Kim @ 2011-05-27 6:00 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-kernel, Paul Clements
Unlike kernel_sendmsg(), kernel_recvmsg() requires passing flags explicitly
via last parameter instead of struct msghdr.msg_flags. Therefore calls to
sock_xmit(lo, 0, ..., MSG_WAITALL) have not been processed properly by tcp
layer wrt. the flag. Fix it.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
---
drivers/block/nbd.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index e6fc716aca45..1df3bfe5225b 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -192,7 +192,8 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size,
if (lo->xmit_timeout)
del_timer_sync(&ti);
} else
- result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);
+ result = kernel_recvmsg(sock, &msg, &iov, 1, size,
+ msg.msg_flags);
if (signal_pending(current)) {
siginfo_t info;
--
1.7.5.2
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 2/3] nbd: limit module parameters to a sane value
2011-05-27 6:00 [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Namhyung Kim
@ 2011-05-27 6:00 ` Namhyung Kim
2011-05-27 12:41 ` Paul Clements
2011-06-06 10:29 ` Pavel Machek
2011-05-27 6:00 ` [PATCH 3/3] nbd: adjust 'max_part' according to part_shift Namhyung Kim
2011-05-27 12:33 ` [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Paul Clements
2 siblings, 2 replies; 7+ messages in thread
From: Namhyung Kim @ 2011-05-27 6:00 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-kernel, Laurent Vivier, Paul Clements, stable
The 'max_part' parameter controls the number of maximum partition
a nbd device can have. However if a user specifies very large
value it would exceed the limitation of device minor number and
can cause a kernel oops (or, at least, produce invalid device
nodes in some cases).
In addition, specifying large 'nbds_max' value causes same
problem for the same reason.
On my desktop, following command results to the kernel bug:
$ sudo modprobe nbd max_part=100000
kernel BUG at /media/Linux_Data/project/linux/fs/sysfs/group.c:65!
invalid opcode: 0000 [#1] SMP
last sysfs file: /sys/devices/virtual/block/nbd4/range
CPU 1
Modules linked in: nbd(+) bridge stp llc kvm_intel kvm asus_atk0110 sg sr_mod cdrom
Pid: 2522, comm: modprobe Tainted: G W 2.6.39-leonard+ #159 System manufacturer System Product Name/P5G41TD-M PRO
RIP: 0010:[<ffffffff8115aa08>] [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
RSP: 0018:ffff8801009f1de8 EFLAGS: 00010246
RAX: 00000000ffffffef RBX: ffff880103920478 RCX: 00000000000a7bd3
RDX: ffffffff81a2dbe0 RSI: 0000000000000000 RDI: ffff880103920478
RBP: ffff8801009f1e38 R08: ffff880103920468 R09: ffff880103920478
R10: ffff8801009f1de8 R11: ffff88011eccbb68 R12: ffffffff81a2dbe0
R13: ffff880103920468 R14: 0000000000000000 R15: ffff880103920400
FS: 00007f3c49de9700(0000) GS:ffff88011f800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f3b7fe7c000 CR3: 00000000cd58d000 CR4: 00000000000406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process modprobe (pid: 2522, threadinfo ffff8801009f0000, task ffff8801009a93a0)
Stack:
ffff8801009f1e58 ffffffff812e8f6e ffff8801009f1e58 ffffffff812e7a80
ffff880000000010 ffff880103920400 ffff8801002fd0c0 ffff880103920468
0000000000000011 ffff880103920400 ffff8801009f1e48 ffffffff8115ab6a
Call Trace:
[<ffffffff812e8f6e>] ? device_add+0x4f1/0x5e4
[<ffffffff812e7a80>] ? dev_set_name+0x41/0x43
[<ffffffff8115ab6a>] sysfs_create_group+0x13/0x15
[<ffffffff810b857e>] blk_trace_init_sysfs+0x14/0x16
[<ffffffff811ee58b>] blk_register_queue+0x4c/0xfd
[<ffffffff811f3bdf>] add_disk+0xe4/0x29c
[<ffffffffa007e2ab>] nbd_init+0x2ab/0x30d [nbd]
[<ffffffffa007e000>] ? 0xffffffffa007dfff
[<ffffffff8100020f>] do_one_initcall+0x7f/0x13e
[<ffffffff8107ab0a>] sys_init_module+0xa1/0x1e3
[<ffffffff814f3542>] system_call_fastpath+0x16/0x1b
Code: 41 57 41 56 41 55 41 54 53 48 83 ec 28 0f 1f 44 00 00 48 89 fb 41 89 f6 49 89 d4 48 85 ff 74 0b 85 f6 75 0b 48 83
7f 30 00 75 14 <0f> 0b eb fe b9 ea ff ff ff 48 83 7f 30 00 0f 84 09 01 00 00 49
RIP [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
RSP <ffff8801009f1de8>
---[ end trace 753285ffbf72c57c ]---
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: stable@kernel.org
---
drivers/block/nbd.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 1df3bfe5225b..fdee7567fd15 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -757,6 +757,12 @@ static int __init nbd_init(void)
if (max_part > 0)
part_shift = fls(max_part);
+ if ((1UL << part_shift) > DISK_MAX_PARTS)
+ return -EINVAL;
+
+ if (nbds_max > 1UL << (MINORBITS - part_shift))
+ return -EINVAL;
+
for (i = 0; i < nbds_max; i++) {
struct gendisk *disk = alloc_disk(1 << part_shift);
if (!disk)
--
1.7.5.2
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 3/3] nbd: adjust 'max_part' according to part_shift
2011-05-27 6:00 [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Namhyung Kim
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
@ 2011-05-27 6:00 ` Namhyung Kim
2011-05-27 12:59 ` Paul Clements
2011-05-27 12:33 ` [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Paul Clements
2 siblings, 1 reply; 7+ messages in thread
From: Namhyung Kim @ 2011-05-27 6:00 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-kernel, Laurent Vivier, Paul Clements
The 'max_part' parameter determines how many partitions are supported
on each nbd device. However the actual number can be changed to the
power of 2 minus 1 form during the module initialization as
alloc_disk() is called with (1 << part_shift) for some reason.
So adjust 'max_part' also at least for consistency with loop and brd.
It is exported via sysfs already, and a user should check this value
after module loading if [s]he wants to use that number correctly
(i.e. fdisk or something).
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: Paul Clements <Paul.Clements@steeleye.com>
---
drivers/block/nbd.c | 13 ++++++++++++-
1 files changed, 12 insertions(+), 1 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index fdee7567fd15..f533f3375e24 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -754,9 +754,20 @@ static int __init nbd_init(void)
return -ENOMEM;
part_shift = 0;
- if (max_part > 0)
+ if (max_part > 0) {
part_shift = fls(max_part);
+ /*
+ * Adjust max_part according to part_shift as it is exported
+ * to user space so that user can know the max number of
+ * partition kernel should be able to manage.
+ *
+ * Note that -1 is required because partition 0 is reserved
+ * for the whole disk.
+ */
+ max_part = (1UL << part_shift) - 1;
+ }
+
if ((1UL << part_shift) > DISK_MAX_PARTS)
return -EINVAL;
--
1.7.5.2
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg()
2011-05-27 6:00 [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Namhyung Kim
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
2011-05-27 6:00 ` [PATCH 3/3] nbd: adjust 'max_part' according to part_shift Namhyung Kim
@ 2011-05-27 12:33 ` Paul Clements
2 siblings, 0 replies; 7+ messages in thread
From: Paul Clements @ 2011-05-27 12:33 UTC (permalink / raw)
To: Namhyung Kim; +Cc: Jens Axboe, linux-kernel
On Fri, May 27, 2011 at 2:00 AM, Namhyung Kim <namhyung@gmail.com> wrote:
> Unlike kernel_sendmsg(), kernel_recvmsg() requires passing flags explicitly
> via last parameter instead of struct msghdr.msg_flags. Therefore calls to
> sock_xmit(lo, 0, ..., MSG_WAITALL) have not been processed properly by tcp
> layer wrt. the flag. Fix it.
Thanks. Good catch. I wonder why recvmsg takes external flags and
sendmsg uses the ones attached to msg? Odd...
--
Paul
> Signed-off-by: Namhyung Kim <namhyung@gmail.com>
> Cc: Paul Clements <Paul.Clements@steeleye.com>
> ---
> drivers/block/nbd.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index e6fc716aca45..1df3bfe5225b 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -192,7 +192,8 @@ static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size,
> if (lo->xmit_timeout)
> del_timer_sync(&ti);
> } else
> - result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);
> + result = kernel_recvmsg(sock, &msg, &iov, 1, size,
> + msg.msg_flags);
>
> if (signal_pending(current)) {
> siginfo_t info;
> --
> 1.7.5.2
>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 2/3] nbd: limit module parameters to a sane value
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
@ 2011-05-27 12:41 ` Paul Clements
2011-06-06 10:29 ` Pavel Machek
1 sibling, 0 replies; 7+ messages in thread
From: Paul Clements @ 2011-05-27 12:41 UTC (permalink / raw)
To: Namhyung Kim; +Cc: Jens Axboe, linux-kernel, Laurent Vivier, stable
On Fri, May 27, 2011 at 2:00 AM, Namhyung Kim <namhyung@gmail.com> wrote:
> The 'max_part' parameter controls the number of maximum partition
> a nbd device can have. However if a user specifies very large
> value it would exceed the limitation of device minor number and
> can cause a kernel oops (or, at least, produce invalid device
> nodes in some cases).
Then don't do that... :)
Patch looks good.
Thanks,
Paul
> In addition, specifying large 'nbds_max' value causes same
> problem for the same reason.
>
> On my desktop, following command results to the kernel bug:
>
> $ sudo modprobe nbd max_part=100000
> kernel BUG at /media/Linux_Data/project/linux/fs/sysfs/group.c:65!
> invalid opcode: 0000 [#1] SMP
> last sysfs file: /sys/devices/virtual/block/nbd4/range
> CPU 1
> Modules linked in: nbd(+) bridge stp llc kvm_intel kvm asus_atk0110 sg sr_mod cdrom
>
> Pid: 2522, comm: modprobe Tainted: G W 2.6.39-leonard+ #159 System manufacturer System Product Name/P5G41TD-M PRO
> RIP: 0010:[<ffffffff8115aa08>] [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
> RSP: 0018:ffff8801009f1de8 EFLAGS: 00010246
> RAX: 00000000ffffffef RBX: ffff880103920478 RCX: 00000000000a7bd3
> RDX: ffffffff81a2dbe0 RSI: 0000000000000000 RDI: ffff880103920478
> RBP: ffff8801009f1e38 R08: ffff880103920468 R09: ffff880103920478
> R10: ffff8801009f1de8 R11: ffff88011eccbb68 R12: ffffffff81a2dbe0
> R13: ffff880103920468 R14: 0000000000000000 R15: ffff880103920400
> FS: 00007f3c49de9700(0000) GS:ffff88011f800000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> CR2: 00007f3b7fe7c000 CR3: 00000000cd58d000 CR4: 00000000000406e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> Process modprobe (pid: 2522, threadinfo ffff8801009f0000, task ffff8801009a93a0)
> Stack:
> ffff8801009f1e58 ffffffff812e8f6e ffff8801009f1e58 ffffffff812e7a80
> ffff880000000010 ffff880103920400 ffff8801002fd0c0 ffff880103920468
> 0000000000000011 ffff880103920400 ffff8801009f1e48 ffffffff8115ab6a
> Call Trace:
> [<ffffffff812e8f6e>] ? device_add+0x4f1/0x5e4
> [<ffffffff812e7a80>] ? dev_set_name+0x41/0x43
> [<ffffffff8115ab6a>] sysfs_create_group+0x13/0x15
> [<ffffffff810b857e>] blk_trace_init_sysfs+0x14/0x16
> [<ffffffff811ee58b>] blk_register_queue+0x4c/0xfd
> [<ffffffff811f3bdf>] add_disk+0xe4/0x29c
> [<ffffffffa007e2ab>] nbd_init+0x2ab/0x30d [nbd]
> [<ffffffffa007e000>] ? 0xffffffffa007dfff
> [<ffffffff8100020f>] do_one_initcall+0x7f/0x13e
> [<ffffffff8107ab0a>] sys_init_module+0xa1/0x1e3
> [<ffffffff814f3542>] system_call_fastpath+0x16/0x1b
> Code: 41 57 41 56 41 55 41 54 53 48 83 ec 28 0f 1f 44 00 00 48 89 fb 41 89 f6 49 89 d4 48 85 ff 74 0b 85 f6 75 0b 48 83
> 7f 30 00 75 14 <0f> 0b eb fe b9 ea ff ff ff 48 83 7f 30 00 0f 84 09 01 00 00 49
> RIP [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
> RSP <ffff8801009f1de8>
> ---[ end trace 753285ffbf72c57c ]---
>
> Signed-off-by: Namhyung Kim <namhyung@gmail.com>
> Cc: Laurent Vivier <Laurent.Vivier@bull.net>
> Cc: Paul Clements <Paul.Clements@steeleye.com>
> Cc: stable@kernel.org
> ---
> drivers/block/nbd.c | 6 ++++++
> 1 files changed, 6 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index 1df3bfe5225b..fdee7567fd15 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -757,6 +757,12 @@ static int __init nbd_init(void)
> if (max_part > 0)
> part_shift = fls(max_part);
>
> + if ((1UL << part_shift) > DISK_MAX_PARTS)
> + return -EINVAL;
> +
> + if (nbds_max > 1UL << (MINORBITS - part_shift))
> + return -EINVAL;
> +
> for (i = 0; i < nbds_max; i++) {
> struct gendisk *disk = alloc_disk(1 << part_shift);
> if (!disk)
> --
> 1.7.5.2
>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 3/3] nbd: adjust 'max_part' according to part_shift
2011-05-27 6:00 ` [PATCH 3/3] nbd: adjust 'max_part' according to part_shift Namhyung Kim
@ 2011-05-27 12:59 ` Paul Clements
0 siblings, 0 replies; 7+ messages in thread
From: Paul Clements @ 2011-05-27 12:59 UTC (permalink / raw)
To: Namhyung Kim; +Cc: Jens Axboe, linux-kernel, Laurent Vivier
On Fri, May 27, 2011 at 2:00 AM, Namhyung Kim <namhyung@gmail.com> wrote:
> The 'max_part' parameter determines how many partitions are supported
> on each nbd device. However the actual number can be changed to the
> power of 2 minus 1 form during the module initialization as
> alloc_disk() is called with (1 << part_shift) for some reason.
>
> So adjust 'max_part' also at least for consistency with loop and brd.
> It is exported via sysfs already, and a user should check this value
> after module loading if [s]he wants to use that number correctly
> (i.e. fdisk or something).
>
> Signed-off-by: Namhyung Kim <namhyung@gmail.com>
> Cc: Laurent Vivier <Laurent.Vivier@bull.net>
> Cc: Paul Clements <Paul.Clements@steeleye.com>
Sure, looks good.
Thanks,
Paul
> ---
> drivers/block/nbd.c | 13 ++++++++++++-
> 1 files changed, 12 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
> index fdee7567fd15..f533f3375e24 100644
> --- a/drivers/block/nbd.c
> +++ b/drivers/block/nbd.c
> @@ -754,9 +754,20 @@ static int __init nbd_init(void)
> return -ENOMEM;
>
> part_shift = 0;
> - if (max_part > 0)
> + if (max_part > 0) {
> part_shift = fls(max_part);
>
> + /*
> + * Adjust max_part according to part_shift as it is exported
> + * to user space so that user can know the max number of
> + * partition kernel should be able to manage.
> + *
> + * Note that -1 is required because partition 0 is reserved
> + * for the whole disk.
> + */
> + max_part = (1UL << part_shift) - 1;
> + }
> +
> if ((1UL << part_shift) > DISK_MAX_PARTS)
> return -EINVAL;
>
> --
> 1.7.5.2
>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 2/3] nbd: limit module parameters to a sane value
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
2011-05-27 12:41 ` Paul Clements
@ 2011-06-06 10:29 ` Pavel Machek
1 sibling, 0 replies; 7+ messages in thread
From: Pavel Machek @ 2011-06-06 10:29 UTC (permalink / raw)
To: Namhyung Kim
Cc: Jens Axboe, linux-kernel, Laurent Vivier, Paul Clements, stable
>
> Signed-off-by: Namhyung Kim <namhyung@gmail.com>
> Cc: Laurent Vivier <Laurent.Vivier@bull.net>
> Cc: Paul Clements <Paul.Clements@steeleye.com>
> Cc: stable@kernel.org
ack. but probably not important enough for stable.
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2011-06-06 10:30 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-05-27 6:00 [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Namhyung Kim
2011-05-27 6:00 ` [PATCH 2/3] nbd: limit module parameters to a sane value Namhyung Kim
2011-05-27 12:41 ` Paul Clements
2011-06-06 10:29 ` Pavel Machek
2011-05-27 6:00 ` [PATCH 3/3] nbd: adjust 'max_part' according to part_shift Namhyung Kim
2011-05-27 12:59 ` Paul Clements
2011-05-27 12:33 ` [PATCH 1/3] nbd: pass MSG_* flags to kernel_recvmsg() Paul Clements
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