The patch titled
Subject: ocfs2: protect extent tree in ocfs2_prepare_inode_for_write()
has been added to the -mm tree. Its filename is
ocfs2-protect-extent-tree-in-the-ocfs2_prepare_inode_for_write.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ocfs2-protect-extent-tree-in-the-ocfs2_prepare_inode_for_write.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ocfs2-protect-extent-tree-in-the-ocfs2_prepare_inode_for_write.patch
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------------------------------------------------------
From: Shuning Zhang <sunny.s.zhang@xxxxxxxxxx>
Subject: ocfs2: protect extent tree in ocfs2_prepare_inode_for_write()
When the extent tree is modified, it should be protected by inode cluster
lock and ip_alloc_sem.
The extent tree is accessed and modified in the
ocfs2_prepare_inode_for_write, but isn't protected by ip_alloc_sem.
The following is a case. The function ocfs2_fiemap is accessing the
extent tree, which is modified at the same time.
[47145.974472] kernel BUG at fs/ocfs2/extent_map.c:475!
[47145.974480] invalid opcode: 0000 [#1] SMP
[47145.974489] Modules linked in: tun ocfs2 ocfs2_nodemanager configfs
ocfs2_stackglue xen_netback xen_blkback xen_gntalloc xen_gntdev xen_evtchn
xenfs xen_privcmd vfat fat bnx2fc fcoe libfcoe libfc scsi_transport_fc sunrpc
bridge 8021q mrp garp stp llc ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad
ib_core ib_addr dm_round_robin dm_multipath sg pcspkr raid1 shpchp
ipmi_devintf ipmi_msghandler ext4 jbd2 mbcache2 sd_mod nvme nvme_core bnxt_en
xhci_pci xhci_hcd crc32c_intel be2iscsi bnx2i cnic uio cxgb4i cxgb4 cxgb3i
libcxgbi ipv6 cxgb3 mdio qla4xxx wmi dm_mirror dm_region_hash dm_log dm_mod
iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi iscsi_ibft
iscsi_boot_sysfs
[47145.974636] CPU: 16 PID: 14047 Comm: o2info Not tainted
4.1.12-124.23.1.el6uek.x86_64 #2
[47145.974646] Hardware name: Oracle Corporation ORACLE SERVER X7-2L/ASM, MB
MECH, X7-2L, BIOS 42040600 10/19/2018
[47145.974658] task: ffff88019487e200 ti: ffff88003daa4000 task.ti:
ffff88003daa4000
[47145.974667] RIP: e030:[<ffffffffa05e4840>] [<ffffffffa05e4840>]
ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2]
[47145.974708] RSP: e02b:ffff88003daa7d88 EFLAGS: 00010287
[47145.974713] RAX: 00000000000000de RBX: ffff8801d1104030 RCX:
ffff8801d1104e10
[47145.974719] RDX: 00000000000000de RSI: 000000000009ec40 RDI:
ffff8801d1104e24
[47145.974725] RBP: ffff88003daa7df8 R08: ffff88003daa7e38 R09:
0000000000000000
[47145.974732] R10: 000000000009ec3f R11: 0000000000000246 R12:
000000000009ec3f
[47145.974739] R13: ffff88004c419000 R14: 0000000000000002 R15:
ffff88003daa7e28
[47145.974754] FS: 00007fdbccc92720(0000) GS:ffff880358800000(0000)
knlGS:ffff880358800000
[47145.974764] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033
[47145.974772] CR2: 00007fd5dfcd8350 CR3: 0000000208677000 CR4:
0000000000042660
[47145.974785] Stack:
[47145.974790] ffff88003daa7df8 00002000a05e249b ffff8801d1104000
ffff88003daa7e2c
[47145.974802] ffff88003daa7e38 ffff88000cc484c0 ffff880145f5b478
0000000000000000
[47145.974811] 0000000000002000 ffff88000cc484c0 ffff88003daa7ea0
0000000000000000
[47145.974820] Call Trace:
[47145.974837] [<ffffffffa05e53e3>] ocfs2_fiemap+0x1e3/0x430 [ocfs2]
[47145.974848] [<ffffffff816f644f>] ? xen_hypervisor_callback+0x7f/0x120
[47145.974855] [<ffffffff816f6448>] ? xen_hypervisor_callback+0x78/0x120
[47145.974861] [<ffffffff816f64a3>] ? xen_hypervisor_callback+0xd3/0x120
[47145.974872] [<ffffffff81220905>] do_vfs_ioctl+0x155/0x510
[47145.974878] [<ffffffff81220d41>] SyS_ioctl+0x81/0xa0
[47145.974885] [<ffffffff816f1b9f>] ? system_call_after_swapgs+0xe9/0x190
[47145.974891] [<ffffffff816f1b98>] ? system_call_after_swapgs+0xe2/0x190
[47145.974899] [<ffffffff816f1b91>] ? system_call_after_swapgs+0xdb/0x190
[47145.974905] [<ffffffff816f1c5e>] system_call_fastpath+0x18/0xd8
[47145.974910] Code: 18 48 c7 c6 60 7f 65 a0 31 c0 bb e2 ff ff ff 48 8b 4a 40
48 8b 7a 28 48 c7 c2 78 2d 66 a0 e8 38 4f 05 00 e9 28 fe ff ff 0f 1f 00 <0f>
0b 66 0f 1f 44 00 00 bb 86 ff ff ff e9 13 fe ff ff 66 0f 1f
[47145.975000] RIP [<ffffffffa05e4840>]
ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2]
[47145.975018] RSP <ffff88003daa7d88>
[47145.989999] ---[ end trace c8aa0c8180e869dc ]---
[47146.087579] Kernel panic - not syncing: Fatal exception
[47146.087691] Kernel Offset: disabled
Link: http://lkml.kernel.org/r/1568772175-2906-2-git-send-email-sunny.s.zhang@xxxxxxxxxx
Signed-off-by: Shuning Zhang <sunny.s.zhang@xxxxxxxxxx>
Reviewed-by: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Reviewed-by: Gang He <ghe@xxxxxxxx>
Cc: Mark Fasheh <mark@xxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Joseph Qi <jiangqi903@xxxxxxxxx>
Cc: Changwei Ge <gechangwei@xxxxxxx>
Cc: Jun Piao <piaojun@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ocfs2/file.c | 126 ++++++++++++++++++++++++++++++++++++----------
1 file changed, 100 insertions(+), 26 deletions(-)
--- a/fs/ocfs2/file.c~ocfs2-protect-extent-tree-in-the-ocfs2_prepare_inode_for_write
+++ a/fs/ocfs2/file.c
@@ -2123,26 +2123,90 @@ out:
return ret;
}
+static int ocfs2_inode_lock_for_extent_tree(struct inode *inode,
+ struct buffer_head **di_bh,
+ int meta_level,
+ int overwrite_io,
+ int write_sem,
+ int wait)
+{
+ int ret = 0;
+
+ if (wait)
+ ret = ocfs2_inode_lock(inode, NULL, meta_level);
+ else
+ ret = ocfs2_try_inode_lock(inode,
+ overwrite_io ? NULL : di_bh, meta_level);
+ if (ret < 0) {
+ goto out;
+ }
+
+ if (wait) {
+ if (write_sem)
+ down_write(&OCFS2_I(inode)->ip_alloc_sem);
+ else
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+ } else {
+ if (write_sem)
+ ret = down_write_trylock(&OCFS2_I(inode)->ip_alloc_sem);
+ else
+ ret = down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem);
+
+ if (!ret) {
+ ret = -EAGAIN;
+ goto out_unlock;
+ }
+ }
+
+ return ret;
+
+out_unlock:
+ brelse(*di_bh);
+ ocfs2_inode_unlock(inode, meta_level);
+out:
+ return ret;
+}
+
+static void ocfs2_inode_unlock_for_extent_tree(struct inode *inode,
+ struct buffer_head **di_bh,
+ int meta_level,
+ int write_sem)
+{
+ if (write_sem)
+ up_write(&OCFS2_I(inode)->ip_alloc_sem);
+ else
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+ brelse(*di_bh);
+ *di_bh = NULL;
+
+ if (meta_level >= 0)
+ ocfs2_inode_unlock(inode, meta_level);
+}
+
static int ocfs2_prepare_inode_for_write(struct file *file,
loff_t pos, size_t count, int wait)
{
int ret = 0, meta_level = 0, overwrite_io = 0;
+ int write_sem = 0
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = d_inode(dentry);
struct buffer_head *di_bh = NULL;
+ u32 cpos;
+ u32 clusters;
/*
* We start with a read level meta lock and only jump to an ex
* if we need to make modifications here.
*/
for(;;) {
- if (wait)
- ret = ocfs2_inode_lock(inode, NULL, meta_level);
- else
- ret = ocfs2_try_inode_lock(inode,
- overwrite_io ? NULL : &di_bh, meta_level);
+ ret = ocfs2_inode_lock_for_extent_tree(inode,
+ &di_bh,
+ meta_level,
+ overwrite_io,
+ write_sem,
+ wait);
if (ret < 0) {
- meta_level = -1;
if (ret != -EAGAIN)
mlog_errno(ret);
goto out;
@@ -2154,15 +2218,8 @@ static int ocfs2_prepare_inode_for_write
*/
if (!wait && !overwrite_io) {
overwrite_io = 1;
- if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) {
- ret = -EAGAIN;
- goto out_unlock;
- }
ret = ocfs2_overwrite_io(inode, di_bh, pos, count);
- brelse(di_bh);
- di_bh = NULL;
- up_read(&OCFS2_I(inode)->ip_alloc_sem);
if (ret < 0) {
if (ret != -EAGAIN)
mlog_errno(ret);
@@ -2181,7 +2238,10 @@ static int ocfs2_prepare_inode_for_write
* set inode->i_size at the end of a write. */
if (should_remove_suid(dentry)) {
if (meta_level == 0) {
- ocfs2_inode_unlock(inode, meta_level);
+ ocfs2_inode_unlock_for_extent_tree(inode,
+ &di_bh,
+ meta_level,
+ write_sem);
meta_level = 1;
continue;
}
@@ -2195,18 +2255,32 @@ static int ocfs2_prepare_inode_for_write
ret = ocfs2_check_range_for_refcount(inode, pos, count);
if (ret == 1) {
- ocfs2_inode_unlock(inode, meta_level);
- meta_level = -1;
+ ocfs2_inode_unlock_for_extent_tree(inode,
+ &di_bh,
+ meta_level,
+ write_sem);
+ ret = ocfs2_inode_lock_for_extent_tree(inode,
+ &di_bh,
+ meta_level,
+ overwrite_io,
+ 1,
+ wait);
+ write_sem = 1;
+ if (ret < 0) {
+ if (ret != -EAGAIN)
+ mlog_errno(ret);
+ goto out;
+ }
- ret = ocfs2_prepare_inode_for_refcount(inode,
- file,
- pos,
- count,
- &meta_level);
+ cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
+ clusters =
+ ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
+ ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX);
}
if (ret < 0) {
- mlog_errno(ret);
+ if (ret != -EAGAIN)
+ mlog_errno(ret);
goto out_unlock;
}
@@ -2217,10 +2291,10 @@ out_unlock:
trace_ocfs2_prepare_inode_for_write(OCFS2_I(inode)->ip_blkno,
pos, count, wait);
- brelse(di_bh);
-
- if (meta_level >= 0)
- ocfs2_inode_unlock(inode, meta_level);
+ ocfs2_inode_unlock_for_extent_tree(inode,
+ &di_bh,
+ meta_level,
+ write_sem);
out:
return ret;
_
Patches currently in -mm which might be from sunny.s.zhang@xxxxxxxxxx are
ocfs2-protect-extent-tree-in-the-ocfs2_prepare_inode_for_write.patch
ocfs2-remove-unused-function-ocfs2_prepare_inode_for_refcount.patch
