diff options
| author |   Kees Cook <keescook@chromium.org> | 2018-09-13 14:23:56 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-09-13 16:53:24 -0700 |
| commit | ee4fccbee7d397c4d937e20d8c76212ffc23a7e3 (patch) | |
| tree | ed87fd2701be59b42b3f8676b22674eed0ff08fc /drivers/net | |
| parent | pktgen: Fix fall-through annotation (diff) | |
| download | linux-dev-ee4fccbee7d397c4d937e20d8c76212ffc23a7e3.tar.xz linux-dev-ee4fccbee7d397c4d937e20d8c76212ffc23a7e3.zip | |
net/ibm/emac: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
removes the VLA used for the emac xaht registers size. Since the size
of registers can only ever be 4 or 8, as detected in emac_init_config(),
the max can be hardcoded and a runtime test added for robustness.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Christian Lamparter <chunkeey@gmail.com>
Cc: Ivan Mikhaylov <ivan@de.ibm.com>
Cc: netdev@vger.kernel.org
Co-developed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/ibm/emac/core.c | 6 | ||||
| -rw-r--r-- | drivers/net/ethernet/ibm/emac/core.h | 3 |
2 files changed, 8 insertions, 1 deletions
diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c index 372664686309..7410a1de8f1d 100644 --- a/drivers/net/ethernet/ibm/emac/core.c +++ b/drivers/net/ethernet/ibm/emac/core.c @@ -423,7 +423,7 @@ static void emac_hash_mc(struct emac_instance *dev) { const int regs = EMAC_XAHT_REGS(dev); u32 *gaht_base = emac_gaht_base(dev); - u32 gaht_temp[regs]; + u32 gaht_temp[EMAC_XAHT_MAX_REGS]; struct netdev_hw_addr *ha; int i; @@ -2964,6 +2964,10 @@ static int emac_init_config(struct emac_instance *dev) dev->xaht_width_shift = EMAC4_XAHT_WIDTH_SHIFT; } + /* This should never happen */ + if (WARN_ON(EMAC_XAHT_REGS(dev) > EMAC_XAHT_MAX_REGS)) + return -ENXIO; + DBG(dev, "features : 0x%08x / 0x%08x\n", dev->features, EMAC_FTRS_POSSIBLE); DBG(dev, "tx_fifo_size : %d (%d gige)\n", dev->tx_fifo_size, dev->tx_fifo_size_gige); DBG(dev, "rx_fifo_size : %d (%d gige)\n", dev->rx_fifo_size, dev->rx_fifo_size_gige); diff --git a/drivers/net/ethernet/ibm/emac/core.h b/drivers/net/ethernet/ibm/emac/core.h index 369de2cfb15b..84caa4a3fc52 100644 --- a/drivers/net/ethernet/ibm/emac/core.h +++ b/drivers/net/ethernet/ibm/emac/core.h @@ -390,6 +390,9 @@ static inline int emac_has_feature(struct emac_instance *dev, #define EMAC4SYNC_XAHT_SLOTS_SHIFT 8 #define EMAC4SYNC_XAHT_WIDTH_SHIFT 5 +/* The largest span between slots and widths above is 3 */ +#define EMAC_XAHT_MAX_REGS (1 << 3) + #define EMAC_XAHT_SLOTS(dev) (1 << (dev)->xaht_slots_shift) #define EMAC_XAHT_WIDTH(dev) (1 << (dev)->xaht_width_shift) #define EMAC_XAHT_REGS(dev) (1 << ((dev)->xaht_slots_shift - \ |