From 1a6974b2c78755ae55d7be738866eb8d57c3ed45 Mon Sep 17 00:00:00 2001 From: Yuval Mintz Date: Sun, 20 Oct 2013 16:51:27 +0200 Subject: [PATCH] bnx2x: Prevent an illegal pointer dereference during panic During a panic, the driver tries to print the Management FW buffer of recent commands. To do so, the driver reads the address of that buffer from a known address. If the buffer is unavailable (e.g., PCI reads don't work, MCP is failing, etc.), the driver will try to access the address it has read, possibly causing a kernel panic. This check 'sanitizes' the access, validating the read value is indeed a valid address inside the management FW's buffers. The patch also removes a read outside the scope of the buffer, which resulted in some unrelated chraracters appearing in the log. Signed-off-by: Yuval Mintz Signed-off-by: Dmitry Kravkov Signed-off-by: Eilon Greenstein Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnx2x/bnx2x.h | 4 +++ .../net/ethernet/broadcom/bnx2x/bnx2x_main.c | 32 +++++++++++++++---- 2 files changed, 29 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h index 97b3d32a98bd..d21742ca2fd2 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h @@ -2498,4 +2498,8 @@ enum bnx2x_pci_bus_speed { }; void bnx2x_set_local_cmng(struct bnx2x *bp); + +#define MCPR_SCRATCH_BASE(bp) \ + (CHIP_IS_E1x(bp) ? MCP_REG_MCPR_SCRATCH : MCP_A_REG_MCPR_SCRATCH) + #endif /* bnx2x.h */ diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c index 60f9e68ea46c..c2609c41340e 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c @@ -751,6 +751,10 @@ static int bnx2x_mc_assert(struct bnx2x *bp) return rc; } +#define MCPR_TRACE_BUFFER_SIZE (0x800) +#define SCRATCH_BUFFER_SIZE(bp) \ + (CHIP_IS_E1(bp) ? 0x10000 : (CHIP_IS_E1H(bp) ? 0x20000 : 0x28000)) + void bnx2x_fw_dump_lvl(struct bnx2x *bp, const char *lvl) { u32 addr, val; @@ -775,7 +779,17 @@ void bnx2x_fw_dump_lvl(struct bnx2x *bp, const char *lvl) trace_shmem_base = bp->common.shmem_base; else trace_shmem_base = SHMEM2_RD(bp, other_shmem_base_addr); - addr = trace_shmem_base - 0x800; + + /* sanity */ + if (trace_shmem_base < MCPR_SCRATCH_BASE(bp) + MCPR_TRACE_BUFFER_SIZE || + trace_shmem_base >= MCPR_SCRATCH_BASE(bp) + + SCRATCH_BUFFER_SIZE(bp)) { + BNX2X_ERR("Unable to dump trace buffer (mark %x)\n", + trace_shmem_base); + return; + } + + addr = trace_shmem_base - MCPR_TRACE_BUFFER_SIZE; /* validate TRCB signature */ mark = REG_RD(bp, addr); @@ -787,14 +801,17 @@ void bnx2x_fw_dump_lvl(struct bnx2x *bp, const char *lvl) /* read cyclic buffer pointer */ addr += 4; mark = REG_RD(bp, addr); - mark = (CHIP_IS_E1x(bp) ? MCP_REG_MCPR_SCRATCH : MCP_A_REG_MCPR_SCRATCH) - + ((mark + 0x3) & ~0x3) - 0x08000000; + mark = MCPR_SCRATCH_BASE(bp) + ((mark + 0x3) & ~0x3) - 0x08000000; + if (mark >= trace_shmem_base || mark < addr + 4) { + BNX2X_ERR("Mark doesn't fall inside Trace Buffer\n"); + return; + } printk("%s" "begin fw dump (mark 0x%x)\n", lvl, mark); printk("%s", lvl); /* dump buffer after the mark */ - for (offset = mark; offset <= trace_shmem_base; offset += 0x8*4) { + for (offset = mark; offset < trace_shmem_base; offset += 0x8*4) { for (word = 0; word < 8; word++) data[word] = htonl(REG_RD(bp, offset + 4*word)); data[8] = 0x0; @@ -11685,9 +11702,6 @@ static int bnx2x_init_bp(struct bnx2x *bp) static int bnx2x_open(struct net_device *dev) { struct bnx2x *bp = netdev_priv(dev); - bool global = false; - int other_engine = BP_PATH(bp) ? 0 : 1; - bool other_load_status, load_status; int rc; bp->stats_init = true; @@ -11703,6 +11717,10 @@ static int bnx2x_open(struct net_device *dev) * Parity recovery is only relevant for PF driver. */ if (IS_PF(bp)) { + int other_engine = BP_PATH(bp) ? 0 : 1; + bool other_load_status, load_status; + bool global = false; + other_load_status = bnx2x_get_load_status(bp, other_engine); load_status = bnx2x_get_load_status(bp, BP_PATH(bp)); if (!bnx2x_reset_is_done(bp, BP_PATH(bp)) || -- 2.20.1