* [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl
@ 2010-09-26 21:19 Christoph Hellwig
2010-09-26 21:19 ` [PATCH 2/6] hfsplus: split hfsplus_ioctl Christoph Hellwig
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:19 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel, stable
Currenly the HFSPLUS_IOC_EXT2_GETFLAGS case never unlocks the BKL, which
can lead to easily reproduced lockups when doing multiple GETFLAGS ioctls.
Fix this by only taking the BKL for the HFSPLUS_IOC_EXT2_SETFLAGS case
as neither HFSPLUS_IOC_EXT2_GETFLAGS not the default error case needs it.
This behaviour was introduced by "hfsplus: Push down BKL into ioctl function"
during the 2.6.35-rc series.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/ioctl.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/ioctl.c 2010-09-26 01:47:23.992790058 +0900
+++ linux-2.6/fs/hfsplus/ioctl.c 2010-09-26 01:49:16.701790597 +0900
@@ -26,7 +26,6 @@ long hfsplus_ioctl(struct file *filp, un
struct inode *inode = filp->f_path.dentry->d_inode;
unsigned int flags;
- lock_kernel();
switch (cmd) {
case HFSPLUS_IOC_EXT2_GETFLAGS:
flags = 0;
@@ -39,6 +38,8 @@ long hfsplus_ioctl(struct file *filp, un
return put_user(flags, (int __user *)arg);
case HFSPLUS_IOC_EXT2_SETFLAGS: {
int err = 0;
+
+ lock_kernel();
err = mnt_want_write(filp->f_path.mnt);
if (err) {
unlock_kernel();
@@ -93,7 +94,6 @@ setflags_out:
return err;
}
default:
- unlock_kernel();
return -ENOTTY;
}
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/6] hfsplus: split hfsplus_ioctl
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
@ 2010-09-26 21:19 ` Christoph Hellwig
2010-09-26 21:20 ` [PATCH 3/6] hfsplus: protect setflags using i_mutex Christoph Hellwig
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:19 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel
Give each ioctl command a function of it's own.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/ioctl.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/ioctl.c 2010-09-26 01:49:16.701790597 +0900
+++ linux-2.6/fs/hfsplus/ioctl.c 2010-09-26 02:01:29.927790059 +0900
@@ -21,78 +21,93 @@
#include <asm/uaccess.h>
#include "hfsplus_fs.h"
-long hfsplus_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags)
{
- struct inode *inode = filp->f_path.dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ unsigned int flags = 0;
+
+ if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_IMMUTABLE)
+ flags |= FS_IMMUTABLE_FL;
+ if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_APPEND)
+ flags |= FS_APPEND_FL;
+ if (HFSPLUS_I(inode).userflags & HFSPLUS_FLG_NODUMP)
+ flags |= FS_NODUMP_FL;
+
+ return put_user(flags, user_flags);
+}
+
+static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
unsigned int flags;
+ int err = 0;
- switch (cmd) {
- case HFSPLUS_IOC_EXT2_GETFLAGS:
- flags = 0;
- if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_IMMUTABLE)
- flags |= FS_IMMUTABLE_FL; /* EXT2_IMMUTABLE_FL */
- if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_APPEND)
- flags |= FS_APPEND_FL; /* EXT2_APPEND_FL */
- if (HFSPLUS_I(inode).userflags & HFSPLUS_FLG_NODUMP)
- flags |= FS_NODUMP_FL; /* EXT2_NODUMP_FL */
- return put_user(flags, (int __user *)arg);
- case HFSPLUS_IOC_EXT2_SETFLAGS: {
- int err = 0;
-
- lock_kernel();
- err = mnt_want_write(filp->f_path.mnt);
- if (err) {
- unlock_kernel();
- return err;
- }
+ lock_kernel();
+ err = mnt_want_write(file->f_path.mnt);
+ if (err)
+ goto out_unlock_kernel;
+
+ if (!is_owner_or_cap(inode)) {
+ err = -EACCES;
+ goto out_drop_write;
+ }
- if (!is_owner_or_cap(inode)) {
- err = -EACCES;
- goto setflags_out;
- }
- if (get_user(flags, (int __user *)arg)) {
- err = -EFAULT;
- goto setflags_out;
- }
- if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
- HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
- if (!capable(CAP_LINUX_IMMUTABLE)) {
- err = -EPERM;
- goto setflags_out;
- }
- }
+ if (get_user(flags, user_flags)) {
+ err = -EFAULT;
+ goto out_drop_write;
+ }
- /* don't silently ignore unsupported ext2 flags */
- if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
- err = -EOPNOTSUPP;
- goto setflags_out;
+ if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
+ HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ err = -EPERM;
+ goto out_drop_write;
}
- if (flags & FS_IMMUTABLE_FL) { /* EXT2_IMMUTABLE_FL */
- inode->i_flags |= S_IMMUTABLE;
- HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_IMMUTABLE;
- } else {
- inode->i_flags &= ~S_IMMUTABLE;
- HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_IMMUTABLE;
- }
- if (flags & FS_APPEND_FL) { /* EXT2_APPEND_FL */
- inode->i_flags |= S_APPEND;
- HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_APPEND;
- } else {
- inode->i_flags &= ~S_APPEND;
- HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_APPEND;
- }
- if (flags & FS_NODUMP_FL) /* EXT2_NODUMP_FL */
- HFSPLUS_I(inode).userflags |= HFSPLUS_FLG_NODUMP;
- else
- HFSPLUS_I(inode).userflags &= ~HFSPLUS_FLG_NODUMP;
-
- inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
-setflags_out:
- mnt_drop_write(filp->f_path.mnt);
- unlock_kernel();
- return err;
}
+
+ /* don't silently ignore unsupported ext2 flags */
+ if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
+ err = -EOPNOTSUPP;
+ goto out_drop_write;
+ }
+ if (flags & FS_IMMUTABLE_FL) {
+ inode->i_flags |= S_IMMUTABLE;
+ HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_IMMUTABLE;
+ } else {
+ inode->i_flags &= ~S_IMMUTABLE;
+ HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_IMMUTABLE;
+ }
+ if (flags & FS_APPEND_FL) {
+ inode->i_flags |= S_APPEND;
+ HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_APPEND;
+ } else {
+ inode->i_flags &= ~S_APPEND;
+ HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_APPEND;
+ }
+ if (flags & FS_NODUMP_FL)
+ HFSPLUS_I(inode).userflags |= HFSPLUS_FLG_NODUMP;
+ else
+ HFSPLUS_I(inode).userflags &= ~HFSPLUS_FLG_NODUMP;
+
+ inode->i_ctime = CURRENT_TIME_SEC;
+ mark_inode_dirty(inode);
+
+out_drop_write:
+ mnt_drop_write(file->f_path.mnt);
+out_unlock_kernel:
+ unlock_kernel();
+ return err;
+}
+
+long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+
+ switch (cmd) {
+ case HFSPLUS_IOC_EXT2_GETFLAGS:
+ return hfsplus_ioctl_getflags(file, argp);
+ case HFSPLUS_IOC_EXT2_SETFLAGS:
+ return hfsplus_ioctl_setflags(file, argp);
default:
return -ENOTTY;
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 3/6] hfsplus: protect setflags using i_mutex
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
2010-09-26 21:19 ` [PATCH 2/6] hfsplus: split hfsplus_ioctl Christoph Hellwig
@ 2010-09-26 21:20 ` Christoph Hellwig
2010-09-26 21:20 ` [PATCH 4/6] hfsplus: introduce alloc_mutex Christoph Hellwig
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:20 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel
Use i_mutex for protecting against concurrent setflags ioctls like in
other filesystems and get rid of the BKL in hfsplus_ioctl.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/ioctl.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/ioctl.c 2010-09-26 02:01:29.927790059 +0900
+++ linux-2.6/fs/hfsplus/ioctl.c 2010-09-26 02:03:03.013790060 +0900
@@ -17,7 +17,6 @@
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/xattr.h>
-#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include "hfsplus_fs.h"
@@ -42,10 +41,9 @@ static int hfsplus_ioctl_setflags(struct
unsigned int flags;
int err = 0;
- lock_kernel();
err = mnt_want_write(file->f_path.mnt);
if (err)
- goto out_unlock_kernel;
+ goto out;
if (!is_owner_or_cap(inode)) {
err = -EACCES;
@@ -57,18 +55,20 @@ static int hfsplus_ioctl_setflags(struct
goto out_drop_write;
}
+ mutex_lock(&inode->i_mutex);
+
if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
if (!capable(CAP_LINUX_IMMUTABLE)) {
err = -EPERM;
- goto out_drop_write;
+ goto out_unlock_inode;
}
}
/* don't silently ignore unsupported ext2 flags */
if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
err = -EOPNOTSUPP;
- goto out_drop_write;
+ goto out_unlock_inode;
}
if (flags & FS_IMMUTABLE_FL) {
inode->i_flags |= S_IMMUTABLE;
@@ -92,10 +92,11 @@ static int hfsplus_ioctl_setflags(struct
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
+out_unlock_inode:
+ mutex_lock(&inode->i_mutex);
out_drop_write:
mnt_drop_write(file->f_path.mnt);
-out_unlock_kernel:
- unlock_kernel();
+out:
return err;
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 4/6] hfsplus: introduce alloc_mutex
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
2010-09-26 21:19 ` [PATCH 2/6] hfsplus: split hfsplus_ioctl Christoph Hellwig
2010-09-26 21:20 ` [PATCH 3/6] hfsplus: protect setflags using i_mutex Christoph Hellwig
@ 2010-09-26 21:20 ` Christoph Hellwig
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: use alloc_mutex in hfsplus_sync_fs Christoph Hellwig
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: remove BKL from hfsplus_put_super Christoph Hellwig
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:20 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel
Use a new per-sb alloc_mutex instead of abusing i_mutex of the alloc_file
to protect block allocations. This gets rid of lockdep nesting warnings
and prepares for extending the scope of alloc_mutex.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/bitmap.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/bitmap.c 2010-09-27 05:23:50.663327792 +0900
+++ linux-2.6/fs/hfsplus/bitmap.c 2010-09-27 05:24:10.656327794 +0900
@@ -29,7 +29,7 @@ int hfsplus_block_allocate(struct super_
return size;
dprint(DBG_BITMAP, "block_allocate: %u,%u,%u\n", size, offset, len);
- mutex_lock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
+ mutex_lock(&HFSPLUS_SB(sb).alloc_mutex);
mapping = HFSPLUS_SB(sb).alloc_file->i_mapping;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS, NULL);
if (IS_ERR(page)) {
@@ -154,7 +154,7 @@ done:
sb->s_dirt = 1;
dprint(DBG_BITMAP, "-> %u,%u\n", start, *max);
out:
- mutex_unlock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
+ mutex_unlock(&HFSPLUS_SB(sb).alloc_mutex);
return start;
}
@@ -175,7 +175,7 @@ int hfsplus_block_free(struct super_bloc
if ((offset + count) > HFSPLUS_SB(sb).total_blocks)
return -2;
- mutex_lock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
+ mutex_lock(&HFSPLUS_SB(sb).alloc_mutex);
mapping = HFSPLUS_SB(sb).alloc_file->i_mapping;
pnr = offset / PAGE_CACHE_BITS;
page = read_mapping_page(mapping, pnr, NULL);
@@ -226,7 +226,7 @@ out:
kunmap(page);
HFSPLUS_SB(sb).free_blocks += len;
sb->s_dirt = 1;
- mutex_unlock(&HFSPLUS_SB(sb).alloc_file->i_mutex);
+ mutex_unlock(&HFSPLUS_SB(sb).alloc_mutex);
return 0;
}
Index: linux-2.6/fs/hfsplus/hfsplus_fs.h
===================================================================
--- linux-2.6.orig/fs/hfsplus/hfsplus_fs.h 2010-09-27 05:22:44.791327791 +0900
+++ linux-2.6/fs/hfsplus/hfsplus_fs.h 2010-09-27 05:23:22.752327920 +0900
@@ -116,6 +116,9 @@ struct hfsplus_sb_info {
struct inode *hidden_dir;
struct nls_table *nls;
+ /* synchronize block allocations */
+ struct mutex alloc_mutex;
+
/* Runtime variables */
u32 blockoffset;
u32 sect_count;
Index: linux-2.6/fs/hfsplus/super.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/super.c 2010-09-27 05:23:26.520327791 +0900
+++ linux-2.6/fs/hfsplus/super.c 2010-09-27 05:23:46.730327733 +0900
@@ -321,6 +321,7 @@ static int hfsplus_fill_super(struct sup
sb->s_fs_info = sbi;
INIT_HLIST_HEAD(&sbi->rsrc_inodes);
+ mutex_init(&sbi->alloc_mutex);
hfsplus_fill_defaults(sbi);
if (!hfsplus_parse_options(data, sbi)) {
printk(KERN_ERR "hfs: unable to parse mount options\n");
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 5/6] hfsplus: use alloc_mutex in hfsplus_sync_fs
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
` (2 preceding siblings ...)
2010-09-26 21:20 ` [PATCH 4/6] hfsplus: introduce alloc_mutex Christoph Hellwig
@ 2010-09-26 21:20 ` Christoph Hellwig
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: remove BKL from hfsplus_put_super Christoph Hellwig
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:20 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel
Use alloc_mutex to protect hfsplus_sync_fs against itself and concurrent
allocations, which allows to get rid of lock_super in hfsplus.
Note that most fields in the superblock still aren't protected against
concurrent allocations, that will follow later.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/super.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/super.c 2010-09-27 05:25:07.450327791 +0900
+++ linux-2.6/fs/hfsplus/super.c 2010-09-27 05:26:11.439327789 +0900
@@ -162,7 +162,7 @@ int hfsplus_sync_fs(struct super_block *
dprint(DBG_SUPER, "hfsplus_write_super\n");
- lock_super(sb);
+ mutex_lock(&HFSPLUS_SB(sb).alloc_mutex);
sb->s_dirt = 0;
vhdr->free_blocks = cpu_to_be32(HFSPLUS_SB(sb).free_blocks);
@@ -195,7 +195,7 @@ int hfsplus_sync_fs(struct super_block *
}
HFSPLUS_SB(sb).flags &= ~HFSPLUS_SB_WRITEBACKUP;
}
- unlock_super(sb);
+ mutex_unlock(&HFSPLUS_SB(sb).alloc_mutex);
return 0;
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 5/6] hfsplus: remove BKL from hfsplus_put_super
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
` (3 preceding siblings ...)
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: use alloc_mutex in hfsplus_sync_fs Christoph Hellwig
@ 2010-09-26 21:20 ` Christoph Hellwig
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2010-09-26 21:20 UTC (permalink / raw)
To: viro, zippel; +Cc: linux-fsdevel
Except for ->put_super the BKL is now gone from HFS, which means it's
superflous there too as ->put_super is serialized by the VFS.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
Index: linux-2.6/fs/hfsplus/super.c
===================================================================
--- linux-2.6.orig/fs/hfsplus/super.c 2010-09-27 05:46:07.172327791 +0900
+++ linux-2.6/fs/hfsplus/super.c 2010-09-27 05:46:21.909327799 +0900
@@ -12,7 +12,6 @@
#include <linux/pagemap.h>
#include <linux/fs.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
#include <linux/vfs.h>
#include <linux/nls.h>
@@ -213,8 +212,6 @@ static void hfsplus_put_super(struct sup
if (!sb->s_fs_info)
return;
- lock_kernel();
-
if (sb->s_dirt)
hfsplus_write_super(sb);
if (!(sb->s_flags & MS_RDONLY) && HFSPLUS_SB(sb).s_vhdr) {
@@ -235,8 +232,6 @@ static void hfsplus_put_super(struct sup
unload_nls(HFSPLUS_SB(sb).nls);
kfree(sb->s_fs_info);
sb->s_fs_info = NULL;
-
- unlock_kernel();
}
static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-09-26 21:26 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-09-26 21:19 [PATCH 1/6] hfsplus: fix BKL leak in hfsplus_ioctl Christoph Hellwig
2010-09-26 21:19 ` [PATCH 2/6] hfsplus: split hfsplus_ioctl Christoph Hellwig
2010-09-26 21:20 ` [PATCH 3/6] hfsplus: protect setflags using i_mutex Christoph Hellwig
2010-09-26 21:20 ` [PATCH 4/6] hfsplus: introduce alloc_mutex Christoph Hellwig
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: use alloc_mutex in hfsplus_sync_fs Christoph Hellwig
2010-09-26 21:20 ` [PATCH 5/6] hfsplus: remove BKL from hfsplus_put_super Christoph Hellwig
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