diff options
| author | Jiangshan Yi <yijiangshan@kylinos.cn> | 2026-07-15 15:35:46 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-07-17 13:07:04 +0200 |
| commit | 7fb13fd7e9a59a37cd911efff83abe19e3ee029d (patch) | |
| tree | c1e67eddfa749993a1989f10fe9b225f16f0c551 | |
| parent | a13c140cc289c0b7b3770bce5b3ad42ab35074aa (diff) | |
| download | linux-next-7fb13fd7e9a59a37cd911efff83abe19e3ee029d.tar.gz linux-next-7fb13fd7e9a59a37cd911efff83abe19e3ee029d.zip | |
serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms
Commit b1b4efea05a5 ("serial: 8250_mid: Disable DMA for selected
platforms") replaced the dnv_board setup and exit callbacks with
PTR_IF(false, ...), which evaluates to NULL. However, the three call
sites in mid8250_probe() and mid8250_remove() unconditionally
dereference these function pointers without NULL checks, causing a NULL
pointer dereference (kernel oops) on any Denverton (DNV), Ice Lake Xeon
D (ICX-D/CDF), or Snowridge (SNR) platform.
Fix this by adding the missing NULL checks before calling the setup and
exit callbacks.
Fixes: b1b4efea05a5 ("serial: 8250_mid: Disable DMA for selected platforms")
Cc: stable <stable@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jiangshan Yi <yijiangshan@kylinos.cn>
Link: https://patch.msgid.link/20260715073546.1875083-1-yijiangshan@kylinos.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/8250/8250_mid.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/tty/serial/8250/8250_mid.c b/drivers/tty/serial/8250/8250_mid.c index f88809ff370b..82656645b8a6 100644 --- a/drivers/tty/serial/8250/8250_mid.c +++ b/drivers/tty/serial/8250/8250_mid.c @@ -318,9 +318,11 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (!uart.port.membase) return -ENOMEM; - ret = mid->board->setup(mid, &uart.port); - if (ret) - return ret; + if (mid->board->setup) { + ret = mid->board->setup(mid, &uart.port); + if (ret) + return ret; + } ret = mid8250_dma_setup(mid, &uart); if (ret) @@ -336,7 +338,8 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id) return 0; err: - mid->board->exit(mid); + if (mid->board->exit) + mid->board->exit(mid); return ret; } @@ -346,7 +349,8 @@ static void mid8250_remove(struct pci_dev *pdev) serial8250_unregister_port(mid->line); - mid->board->exit(mid); + if (mid->board->exit) + mid->board->exit(mid); } static const struct mid8250_board pnw_board = { |