diff options
| author | Matthew Wilcox <willy@infradead.org> | 2019-04-05 14:02:10 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-11 12:22:45 +0200 |
| commit | 9557090582a33801349f0a0920a55d134a27e740 (patch) | |
| tree | b00054a031b80755978735b44bc6e0ad017a1859 /fs/pipe.c | |
| parent | 6f3433c47e8223c97746ad227d1e6f5531e0758a (diff) | |
fs: prevent page refcount overflow in pipe_buf_get
commit 15fab63e1e57be9fdb5eec1bbc5916e9825e9acb upstream.
Change pipe_buf_get() to return a bool indicating whether it succeeded
in raising the refcount of the page (if the thing in the pipe is a page).
This removes another mechanism for overflowing the page refcount. All
callers converted to handle a failure.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/pipe.c')
| -rw-r--r-- | fs/pipe.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 388e09a689de..347c6dc888c8 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -193,9 +193,9 @@ EXPORT_SYMBOL(generic_pipe_buf_steal); * in the tee() system call, when we duplicate the buffers in one * pipe into another. */ -void generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf) +bool generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { - get_page(buf->page); + return try_get_page(buf->page); } EXPORT_SYMBOL(generic_pipe_buf_get); |