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| author | Wu Fengguang <fengguang.wu@intel.com> | 2010-03-05 13:42:01 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-06 11:26:25 -0800 |
| commit | 42e49608683ab25fbbbf9c40edb944601e543882 (patch) | |
| tree | 5cc8beee91f235cdaf6be986f90275e04137c2bc | |
| parent | 85f1fb72fa76eabc4481dc79f42d2b011df54762 (diff) | |
| download | linux-3.10-42e49608683ab25fbbbf9c40edb944601e543882.tar.gz linux-3.10-42e49608683ab25fbbbf9c40edb944601e543882.tar.bz2 linux-3.10-42e49608683ab25fbbbf9c40edb944601e543882.zip | |
vfs: take f_lock on modifying f_mode after open time
We'll introduce FMODE_RANDOM which will be runtime modified. So protect
all runtime modification to f_mode with f_lock to avoid races.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@kernel.org> [2.6.33.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/file_table.c | 2 | ||||
| -rw-r--r-- | fs/nfsd/nfs4state.c | 2 |
2 files changed, 4 insertions, 0 deletions
diff --git a/fs/file_table.c b/fs/file_table.c index b98404b5438..32d12b78bac 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -393,7 +393,9 @@ retry: continue; if (!(f->f_mode & FMODE_WRITE)) continue; + spin_lock(&f->f_lock); f->f_mode &= ~FMODE_WRITE; + spin_unlock(&f->f_lock); if (file_check_writeable(f) != 0) continue; file_release_write(f); diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index f19ed866c95..fcafe6087f6 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1998,7 +1998,9 @@ nfs4_file_downgrade(struct file *filp, unsigned int share_access) { if (share_access & NFS4_SHARE_ACCESS_WRITE) { drop_file_write_access(filp); + spin_lock(&filp->f_lock); filp->f_mode = (filp->f_mode | FMODE_READ) & ~FMODE_WRITE; + spin_unlock(&filp->f_lock); } } |