diff options
| author | Guangshuo Li <lgs201920130244@gmail.com> | 2026-03-27 01:14:12 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-04-11 14:29:51 +0200 |
| commit | 625fdac41cfc4ca9e1774a0d31d7985aec2c1d66 (patch) | |
| tree | ce381a7524f43cf378e7eded43beff67b1b9fde0 | |
| parent | ebc2fcdba47d01731df2e1aff1d81c8d1d4c0527 (diff) | |
auxdisplay: line-display: fix NULL dereference in linedisp_release
commit 7f138de156b20d9f9da6f72f90b63c01941d97d3 upstream.
linedisp_release() currently retrieves the enclosing struct linedisp via
to_linedisp(). That lookup depends on the attachment list, but the
attachment may already have been removed before put_device() invokes the
release callback. This can happen in linedisp_unregister(), and can also
be reached from some linedisp_register() error paths.
In that case, to_linedisp() returns NULL and linedisp_release()
dereferences it while freeing the display resources.
The struct device released here is the embedded linedisp->dev used by
linedisp_register(), so retrieve the enclosing object directly with
container_of() instead.
Fixes: 66c93809487e ("auxdisplay: linedisp: encapsulate container_of usage within to_linedisp")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/auxdisplay/line-display.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/auxdisplay/line-display.c b/drivers/auxdisplay/line-display.c index 4e22373fcc1a..e80e94262830 100644 --- a/drivers/auxdisplay/line-display.c +++ b/drivers/auxdisplay/line-display.c @@ -365,7 +365,7 @@ static DEFINE_IDA(linedisp_id); static void linedisp_release(struct device *dev) { - struct linedisp *linedisp = to_linedisp(dev); + struct linedisp *linedisp = container_of(dev, struct linedisp, dev); kfree(linedisp->map); kfree(linedisp->message); |