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| author | Al Viro <viro@ftp.linux.org.uk> | 2006-04-26 08:32:40 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-04-26 16:52:21 +0200 |
| commit | a090d9132c1e53e3517111123680c15afb25c0a4 (patch) | |
| tree | 7654cbd50a49d1140c71112ce79387bfbc6c0c86 | |
| parent | [PATCH] fix mips sys32_p{read,write} (diff) | |
| download | linux-a090d9132c1e53e3517111123680c15afb25c0a4.tar.xz linux-a090d9132c1e53e3517111123680c15afb25c0a4.zip | |
[PATCH] protect ext3 ioctl modifying append_only, immutable, etc. with i_mutex
All modifications of ->i_flags in inodes that might be visible to
somebody else must be under ->i_mutex. That patch fixes ext3 ioctl()
setting S_APPEND and friends.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | fs/ext3/ioctl.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/fs/ext3/ioctl.c b/fs/ext3/ioctl.c index aaf1da17b6d4..8c22aa9a7fbb 100644 --- a/fs/ext3/ioctl.c +++ b/fs/ext3/ioctl.c @@ -48,6 +48,7 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, if (!S_ISDIR(inode->i_mode)) flags &= ~EXT3_DIRSYNC_FL; + mutex_lock(&inode->i_mutex); oldflags = ei->i_flags; /* The JOURNAL_DATA flag is modifiable only by root */ @@ -60,8 +61,10 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, * This test looks nicer. Thanks to Pauline Middelink */ if ((flags ^ oldflags) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) { - if (!capable(CAP_LINUX_IMMUTABLE)) + if (!capable(CAP_LINUX_IMMUTABLE)) { + mutex_unlock(&inode->i_mutex); return -EPERM; + } } /* @@ -69,14 +72,18 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, * the relevant capability. */ if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) { - if (!capable(CAP_SYS_RESOURCE)) + if (!capable(CAP_SYS_RESOURCE)) { + mutex_unlock(&inode->i_mutex); return -EPERM; + } } handle = ext3_journal_start(inode, 1); - if (IS_ERR(handle)) + if (IS_ERR(handle)) { + mutex_unlock(&inode->i_mutex); return PTR_ERR(handle); + } if (IS_SYNC(inode)) handle->h_sync = 1; err = ext3_reserve_inode_write(handle, inode, &iloc); @@ -93,11 +100,14 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, err = ext3_mark_iloc_dirty(handle, inode, &iloc); flags_err: ext3_journal_stop(handle); - if (err) + if (err) { + mutex_unlock(&inode->i_mutex); return err; + } if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) err = ext3_change_inode_journal_flag(inode, jflag); + mutex_unlock(&inode->i_mutex); return err; } case EXT3_IOC_GETVERSION: |