Dynamic static allocation is evil, as Kernel stack is too low, and compilation complains about it on some archs: drivers/media/dvb-frontends/bcm3510.c:230:1: warning: 'bcm3510_do_hab_cmd' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/itd1000.c:69:1: warning: 'itd1000_write_regs.constprop.0' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/mt312.c:126:1: warning: 'mt312_write' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/nxt200x.c:111:1: warning: 'nxt200x_writebytes' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/stb6100.c:216:1: warning: 'stb6100_write_reg_range.constprop.3' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/stv6110.c:98:1: warning: 'stv6110_write_regs' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/stv6110x.c:85:1: warning: 'stv6110x_write_regs' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/tda18271c2dd.c:147:1: warning: 'WriteRegs' uses dynamic stack allocation [enabled by default] drivers/media/dvb-frontends/zl10039.c:119:1: warning: 'zl10039_write' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer. Considering that I2C transfers are generally limited, and that devices used on USB has a max data length of 80, it seem safe to use 80 as the hard limit for all those devices. On most cases, the limit is a way lower than that, but 80 is small enough to not affect the Kernel stack, and it is a no brain limit, as using smaller ones would require to either carefully each driver or to take a look on each datasheet. Signed-off-by: Mauro Carvalho Chehab <m.chehab@xxxxxxxxxxx> --- drivers/media/dvb-frontends/bcm3510.c | 12 +++++++++++- drivers/media/dvb-frontends/itd1000.c | 10 +++++++++- drivers/media/dvb-frontends/mt312.c | 8 +++++++- drivers/media/dvb-frontends/nxt200x.c | 8 +++++++- drivers/media/dvb-frontends/stb6100.c | 9 ++++++++- drivers/media/dvb-frontends/stv6110.c | 9 ++++++++- drivers/media/dvb-frontends/stv6110x.c | 9 ++++++++- drivers/media/dvb-frontends/tda18271c2dd.c | 11 +++++++++-- drivers/media/dvb-frontends/zl10039.c | 9 ++++++++- 9 files changed, 75 insertions(+), 10 deletions(-) diff --git a/drivers/media/dvb-frontends/bcm3510.c b/drivers/media/dvb-frontends/bcm3510.c index 1b77909c0c71..efd8ce671caf 100644 --- a/drivers/media/dvb-frontends/bcm3510.c +++ b/drivers/media/dvb-frontends/bcm3510.c @@ -201,9 +201,19 @@ static int bcm3510_hab_send_request(struct bcm3510_state *st, u8 *buf, int len) static int bcm3510_do_hab_cmd(struct bcm3510_state *st, u8 cmd, u8 msgid, u8 *obuf, u8 olen, u8 *ibuf, u8 ilen) { - u8 ob[olen+2],ib[ilen+2]; + u8 ob[128], ib[128]; int ret = 0; + if (ilen + 2 > sizeof(ib)) { + deb_hab("do_hab_cmd: ilen=%d is too big!\n", ilen); + return -EREMOTEIO; + } + + if (olen + 2 > sizeof(ob)) { + deb_hab("do_hab_cmd: olen=%d is too big!\n", olen); + return -EREMOTEIO; + } + ob[0] = cmd; ob[1] = msgid; memcpy(&ob[2],obuf,olen); diff --git a/drivers/media/dvb-frontends/itd1000.c b/drivers/media/dvb-frontends/itd1000.c index c1c3400b2173..1a8e9f83a002 100644 --- a/drivers/media/dvb-frontends/itd1000.c +++ b/drivers/media/dvb-frontends/itd1000.c @@ -52,10 +52,18 @@ MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off)."); /* don't write more than one byte with flexcop behind */ static int itd1000_write_regs(struct itd1000_state *state, u8 reg, u8 v[], u8 len) { - u8 buf[1+len]; + u8 buf[80]; struct i2c_msg msg = { .addr = state->cfg->i2c_address, .flags = 0, .buf = buf, .len = len+1 }; + + if (1 + len > sizeof(buf)) { + printk(KERN_WARNING + "itd1000: i2c wr reg=%04x: len=%d is too big!\n", + reg, len); + return -EREMOTEIO; + } + buf[0] = reg; memcpy(&buf[1], v, len); diff --git a/drivers/media/dvb-frontends/mt312.c b/drivers/media/dvb-frontends/mt312.c index ec388c1d6913..fee0e7938f48 100644 --- a/drivers/media/dvb-frontends/mt312.c +++ b/drivers/media/dvb-frontends/mt312.c @@ -96,9 +96,15 @@ static int mt312_write(struct mt312_state *state, const enum mt312_reg_addr reg, const u8 *src, const size_t count) { int ret; - u8 buf[count + 1]; + u8 buf[80]; struct i2c_msg msg; + if (1 + count > sizeof(buf)) { + printk(KERN_WARNING + "mt312: write: len=%zd is too big!\n", count); + return -EREMOTEIO; + } + if (debug) { int i; dprintk("W(%d):", reg & 0x7f); diff --git a/drivers/media/dvb-frontends/nxt200x.c b/drivers/media/dvb-frontends/nxt200x.c index 8e288940a61f..335b35ce60c8 100644 --- a/drivers/media/dvb-frontends/nxt200x.c +++ b/drivers/media/dvb-frontends/nxt200x.c @@ -95,10 +95,16 @@ static int i2c_readbytes(struct nxt200x_state *state, u8 addr, u8 *buf, u8 len) static int nxt200x_writebytes (struct nxt200x_state* state, u8 reg, const u8 *buf, u8 len) { - u8 buf2 [len+1]; + u8 buf2[80]; int err; struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf2, .len = len + 1 }; + if (1 + len > sizeof(buf2)) { + pr_warn("%s: i2c wr reg=%04x: len=%d is too big!\n", + __func__, reg, len); + return -EREMOTEIO; + } + buf2[0] = reg; memcpy(&buf2[1], buf, len); diff --git a/drivers/media/dvb-frontends/stb6100.c b/drivers/media/dvb-frontends/stb6100.c index 45f9523f968f..5623af5fcdd4 100644 --- a/drivers/media/dvb-frontends/stb6100.c +++ b/drivers/media/dvb-frontends/stb6100.c @@ -183,7 +183,7 @@ static int stb6100_read_reg(struct stb6100_state *state, u8 reg) static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int start, int len) { int rc; - u8 cmdbuf[len + 1]; + u8 cmdbuf[80]; struct i2c_msg msg = { .addr = state->config->tuner_address, .flags = 0, @@ -191,6 +191,13 @@ static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int st .len = len + 1 }; + if (1 + len > sizeof(buf)) { + printk(KERN_WARNING + "%s: i2c wr: len=%d is too big!\n", + KBUILD_MODNAME, len); + return -EREMOTEIO; + } + if (unlikely(start < 1 || start + len > STB6100_NUMREGS)) { dprintk(verbose, FE_ERROR, 1, "Invalid register range %d:%d", start, len); diff --git a/drivers/media/dvb-frontends/stv6110.c b/drivers/media/dvb-frontends/stv6110.c index 20b5fa92c53e..4bb3f9a1cf2a 100644 --- a/drivers/media/dvb-frontends/stv6110.c +++ b/drivers/media/dvb-frontends/stv6110.c @@ -68,7 +68,7 @@ static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[], { struct stv6110_priv *priv = fe->tuner_priv; int rc; - u8 cmdbuf[len + 1]; + u8 cmdbuf[80]; struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, @@ -78,6 +78,13 @@ static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[], dprintk("%s\n", __func__); + if (1 + len > sizeof(cmdbuf)) { + printk(KERN_WARNING + "%s: i2c wr: len=%d is too big!\n", + KBUILD_MODNAME, len); + return -EREMOTEIO; + } + if (start + len > 8) return -EINVAL; diff --git a/drivers/media/dvb-frontends/stv6110x.c b/drivers/media/dvb-frontends/stv6110x.c index f36cab12bdc7..41f1d34f64ac 100644 --- a/drivers/media/dvb-frontends/stv6110x.c +++ b/drivers/media/dvb-frontends/stv6110x.c @@ -61,7 +61,7 @@ static int stv6110x_write_regs(struct stv6110x_state *stv6110x, int start, u8 da { int ret; const struct stv6110x_config *config = stv6110x->config; - u8 buf[len + 1]; + u8 buf[80]; struct i2c_msg msg = { .addr = config->addr, .flags = 0, @@ -69,6 +69,13 @@ static int stv6110x_write_regs(struct stv6110x_state *stv6110x, int start, u8 da .len = len + 1 }; + if (1 + len > sizeof(buf)) { + printk(KERN_WARNING + "%s: i2c wr: len=%d is too big!\n", + KBUILD_MODNAME, len); + return -EREMOTEIO; + } + if (start + len > 8) return -EINVAL; diff --git a/drivers/media/dvb-frontends/tda18271c2dd.c b/drivers/media/dvb-frontends/tda18271c2dd.c index d281f77d5c28..d3aa82cd4eb7 100644 --- a/drivers/media/dvb-frontends/tda18271c2dd.c +++ b/drivers/media/dvb-frontends/tda18271c2dd.c @@ -139,11 +139,18 @@ static int i2c_write(struct i2c_adapter *adap, u8 adr, u8 *data, int len) static int WriteRegs(struct tda_state *state, u8 SubAddr, u8 *Regs, u16 nRegs) { - u8 data[nRegs+1]; + u8 data[80]; + + if (1 + nRegs > sizeof(data)) { + printk(KERN_WARNING + "%s: i2c wr: len=%d is too big!\n", + KBUILD_MODNAME, nRegs); + return -EREMOTEIO; + } data[0] = SubAddr; memcpy(data + 1, Regs, nRegs); - return i2c_write(state->i2c, state->adr, data, nRegs+1); + return i2c_write(state->i2c, state->adr, data, nRegs + 1); } static int WriteReg(struct tda_state *state, u8 SubAddr, u8 Reg) diff --git a/drivers/media/dvb-frontends/zl10039.c b/drivers/media/dvb-frontends/zl10039.c index eff9c5fde50a..1e2d99b47bc3 100644 --- a/drivers/media/dvb-frontends/zl10039.c +++ b/drivers/media/dvb-frontends/zl10039.c @@ -98,7 +98,7 @@ static int zl10039_write(struct zl10039_state *state, const enum zl10039_reg_addr reg, const u8 *src, const size_t count) { - u8 buf[count + 1]; + u8 buf[80]; struct i2c_msg msg = { .addr = state->i2c_addr, .flags = 0, @@ -106,6 +106,13 @@ static int zl10039_write(struct zl10039_state *state, .len = count + 1, }; + if (1 + count > sizeof(buf)) { + printk(KERN_WARNING + "%s: i2c wr reg=%04x: len=%zd is too big!\n", + KBUILD_MODNAME, reg, count); + return -EREMOTEIO; + } + dprintk("%s\n", __func__); /* Write register address and data in one go */ buf[0] = reg; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html