Commit graph

8 commits

Author SHA1 Message Date
Al Viro
dcdbd7b269 net/9p: remove (now-)unused helpers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:28:29 -04:00
Sasha Levin
110ecd69a9 9p: fix off by one causing access violations and memory corruption
p9_release_pages() would attempt to dereference one value past the end of
pages[]. This would cause the following crashes:

[ 6293.171817] BUG: unable to handle kernel paging request at ffff8807c96f3000
[ 6293.174146] IP: [<ffffffff8412793b>] p9_release_pages+0x3b/0x60
[ 6293.176447] PGD 79c5067 PUD 82c1e3067 PMD 82c197067 PTE 80000007c96f3060
[ 6293.180060] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 6293.180060] Modules linked in:
[ 6293.180060] CPU: 62 PID: 174043 Comm: modprobe Tainted: G        W    3.10.0-next-20130710-sasha #3954
[ 6293.180060] task: ffff8807b803b000 ti: ffff880787dde000 task.ti: ffff880787dde000
[ 6293.180060] RIP: 0010:[<ffffffff8412793b>]  [<ffffffff8412793b>] p9_release_pages+0x3b/0x60
[ 6293.214316] RSP: 0000:ffff880787ddfc28  EFLAGS: 00010202
[ 6293.214316] RAX: 0000000000000001 RBX: ffff8807c96f2ff8 RCX: 0000000000000000
[ 6293.222017] RDX: ffff8807b803b000 RSI: 0000000000000001 RDI: ffffea001c7e3d40
[ 6293.222017] RBP: ffff880787ddfc48 R08: 0000000000000000 R09: 0000000000000000
[ 6293.222017] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
[ 6293.222017] R13: 0000000000000001 R14: ffff8807cc50c070 R15: ffff8807cc50c070
[ 6293.222017] FS:  00007f572641d700(0000) GS:ffff8807f3600000(0000) knlGS:0000000000000000
[ 6293.256784] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 6293.256784] CR2: ffff8807c96f3000 CR3: 00000007c8e81000 CR4: 00000000000006e0
[ 6293.256784] Stack:
[ 6293.256784]  ffff880787ddfcc8 ffff880787ddfcc8 0000000000000000 ffff880787ddfcc8
[ 6293.256784]  ffff880787ddfd48 ffffffff84128be8 ffff880700000002 0000000000000001
[ 6293.256784]  ffff8807b803b000 ffff880787ddfce0 0000100000000000 0000000000000000
[ 6293.256784] Call Trace:
[ 6293.256784]  [<ffffffff84128be8>] p9_virtio_zc_request+0x598/0x630
[ 6293.256784]  [<ffffffff8115c610>] ? wake_up_bit+0x40/0x40
[ 6293.256784]  [<ffffffff841209b1>] p9_client_zc_rpc+0x111/0x3a0
[ 6293.256784]  [<ffffffff81174b78>] ? sched_clock_cpu+0x108/0x120
[ 6293.256784]  [<ffffffff84122a21>] p9_client_read+0xe1/0x2c0
[ 6293.256784]  [<ffffffff81708a90>] v9fs_file_read+0x90/0xc0
[ 6293.256784]  [<ffffffff812bd073>] vfs_read+0xc3/0x130
[ 6293.256784]  [<ffffffff811a78bd>] ? trace_hardirqs_on+0xd/0x10
[ 6293.256784]  [<ffffffff812bd5a2>] SyS_read+0x62/0xa0
[ 6293.256784]  [<ffffffff841a1a00>] tracesys+0xdd/0xe2
[ 6293.256784] Code: 66 90 48 89 fb 41 89 f5 48 8b 3f 48 85 ff 74 29 85 f6 74 25 45 31 e4 66 0f 1f 84 00 00 00 00 00 e8 eb 14 12 fd 41 ff c4 49 63 c4 <48> 8b 3c c3 48 85 ff 74 05 45 39 e5 75 e7 48 83 c4 08 5b 41 5c
[ 6293.256784] RIP  [<ffffffff8412793b>] p9_release_pages+0x3b/0x60
[ 6293.256784]  RSP <ffff880787ddfc28>
[ 6293.256784] CR2: ffff8807c96f3000
[ 6293.256784] ---[ end trace 50822ee72cd360fc ]---

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11 11:36:02 -07:00
Aneesh Kumar K.V
abfa034e4b fs/9p: Update zero-copy implementation in 9p
* remove lot of update to different data structure
* add a seperate callback for zero copy request.
* above makes non zero copy code path simpler
* remove conditionalizing TREAD/TREADDIR/TWRITE in the zero copy path
* Fix the dotu p9_check_errors with zero copy. Add sufficient doc around
* Add support for both in and output buffers in zero copy callback
* pin and unpin pages in the same context
* use helpers instead of defining page offset and rest of page ourself
* Fix mem leak in p9_check_errors
* Remove 'E' and 'F' in p9pdu_vwritef

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-10-24 11:13:11 -05:00
M. Mohan Kumar
3cd7967825 net/9p: Handle get_user_pages_fast return properly
Use proper data type to handle get_user_pages_fast error condition. Also
do not treat EFAULT error as fatal.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-05-09 22:51:12 -05:00
Aneesh Kumar K.V
bd8c8ade6b 9p: Fix sparse error
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-04-15 15:26:14 -05:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Aneesh Kumar K.V
472e7f9f8b net/9p: Fix compile warning
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:35 -05:00
Venkateswararao Jujjuri (JV)
022cae3655 [net/9p] Preparation and helper functions for zero copy
This patch prepares p9_fcall structure for zero copy. Added
fields send the payload buffer information to the transport layer.
In addition it adds a 'private' field for the transport layer to
store mapped/pinned page information so that it can be freed/unpinned
during req_done.

This patch also creates trans_common.[ch] to house helper functions.
It adds the following helper functions.

p9_release_req_pages - Release pages after the transaction.
p9_nr_pages - Return number of pages needed to accomodate the payload.
payload_gup - Translates user buffer into kernel pages.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-15 09:57:34 -05:00