From a5410cd77500f0ce2eeb0d598a22c2af5ef5ac14 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Tue, 11 Mar 2025 08:51:19 +0900 Subject: [PATCH] spi: tegra210-quad: Avoid shift-out-of-bounds BugLink: https://bugs.launchpad.net/bugs/2101915 [ Upstream commit f399051ec1ff02e74ae5c2517aed2cc486fd005b ] A shift-out-of-bounds issue was identified by UBSAN in the tegra_qspi_fill_tx_fifo_from_client_txbuf() function. UBSAN: shift-out-of-bounds in drivers/spi/spi-tegra210-quad.c:345:27 shift exponent 32 is too large for 32-bit type 'u32' (aka 'unsigned int') Call trace: tegra_qspi_start_cpu_based_transfer The problem arises when shifting the contents of tx_buf left by 8 times the value of i, which can exceed 4 and result in an exponent larger than 32 bits. Resolve this by restrict the value of i to be less than 4, preventing the shift operation from overflowing. Signed-off-by: Breno Leitao Fixes: 921fc1838fb0 ("spi: tegra210-quad: Add support for Tegra210 QSPI controller") Link: https://patch.msgid.link/20241004125400.1791089-1-leitao@debian.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin Signed-off-by: Koichiro Den Signed-off-by: Stefan Bader --- drivers/spi/spi-tegra210-quad.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c index afbd64a217eb..43f11b0e9e76 100644 --- a/drivers/spi/spi-tegra210-quad.c +++ b/drivers/spi/spi-tegra210-quad.c @@ -341,7 +341,7 @@ tegra_qspi_fill_tx_fifo_from_client_txbuf(struct tegra_qspi *tqspi, struct spi_t for (count = 0; count < max_n_32bit; count++) { u32 x = 0; - for (i = 0; len && (i < bytes_per_word); i++, len--) + for (i = 0; len && (i < min(4, bytes_per_word)); i++, len--) x |= (u32)(*tx_buf++) << (i * 8); tegra_qspi_writel(tqspi, x, QSPI_TX_FIFO); }