Hi, Improper use of memcpy() without verifying result from malloc() may cause null pointer dereference --------------------------- linux-3.15.1/drivers/staging/ft1000/ft1000-usb/ft1000_hw.c /* send a command to ASIC * Parameters: ft1000_usb - device structure * ptempbuffer - command buffer * size - command buffer size */ void card_send_command(struct ft1000_usb *ft1000dev, void *ptempbuffer, int size) { unsigned short temp; unsigned char *commandbuf; DEBUG("card_send_command: enter card_send_command... size=%d\n", size); commandbuf = kmalloc(size + 2, GFP_KERNEL); <============== possible NULL memcpy((void *)commandbuf + 2, (void *)ptempbuffer, size); <======= CRASH --------------------------- Patch: kmalloc() result check was lacking. Fixing that required also changing card_send_command() return type from void to int, and checking its return code everywhere. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=78561 Reported-by: Maksymilian Arciemowicz <max@cert.cx> Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com> --- drivers/staging/ft1000/ft1000-usb/ft1000_debug.c | 6 +++--- drivers/staging/ft1000/ft1000-usb/ft1000_hw.c | 25 +++++++++++++++++------- drivers/staging/ft1000/ft1000-usb/ft1000_usb.h | 2 +- 3 files changed, 22 insertions(+), 11 deletions(-) diff --git a/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c b/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c index a8945b7..9f4c785 100644 --- a/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c +++ b/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c @@ -482,14 +482,14 @@ static long ft1000_ioctl(struct file *file, unsigned int command, /* Connect Message */ DEBUG("FT1000:ft1000_ioctl: IOCTL_FT1000_CONNECT\n"); ConnectionMsg[79] = 0xfc; - card_send_command(ft1000dev, (unsigned short *)ConnectionMsg, 0x4c); + result = card_send_command(ft1000dev, (unsigned short *)ConnectionMsg, 0x4c); break; case IOCTL_DISCONNECT: /* Disconnect Message */ DEBUG("FT1000:ft1000_ioctl: IOCTL_FT1000_DISCONNECT\n"); ConnectionMsg[79] = 0xfd; - card_send_command(ft1000dev, (unsigned short *)ConnectionMsg, 0x4c); + result = card_send_command(ft1000dev, (unsigned short *)ConnectionMsg, 0x4c); break; case IOCTL_GET_DSP_STAT_CMD: /* DEBUG("FT1000:ft1000_ioctl: IOCTL_FT1000_GET_DSP_STAT called\n"); */ @@ -652,7 +652,7 @@ static long ft1000_ioctl(struct file *file, unsigned int command, } pmsg++; ppseudo_hdr = (struct pseudo_hdr *)pmsg; - card_send_command(ft1000dev,(unsigned short*)dpram_data,total_len+2); + result = card_send_command(ft1000dev,(unsigned short*)dpram_data,total_len+2); ft1000dev->app_info[app_index].nTxMsg++; diff --git a/drivers/staging/ft1000/ft1000-usb/ft1000_hw.c b/drivers/staging/ft1000/ft1000-usb/ft1000_hw.c index b6a7708..7012e09 100644 --- a/drivers/staging/ft1000/ft1000-usb/ft1000_hw.c +++ b/drivers/staging/ft1000/ft1000-usb/ft1000_hw.c @@ -322,18 +322,23 @@ static void card_reset_dsp(struct ft1000_usb *ft1000dev, bool value) * ptempbuffer - command buffer * size - command buffer size */ -void card_send_command(struct ft1000_usb *ft1000dev, void *ptempbuffer, +int card_send_command(struct ft1000_usb *ft1000dev, void *ptempbuffer, int size) { + int ret; unsigned short temp; unsigned char *commandbuf; DEBUG("card_send_command: enter card_send_command... size=%d\n", size); commandbuf = kmalloc(size + 2, GFP_KERNEL); + if (!commandbuf) + return -ENOMEM; memcpy((void *)commandbuf + 2, (void *)ptempbuffer, size); - ft1000_read_register(ft1000dev, &temp, FT1000_REG_DOORBELL); + ret = ft1000_read_register(ft1000dev, &temp, FT1000_REG_DOORBELL); + if (ret) + return ret; if (temp & 0x0100) usleep_range(900, 1100); @@ -345,19 +350,23 @@ void card_send_command(struct ft1000_usb *ft1000dev, void *ptempbuffer, if (size % 4) size += 4 - (size % 4); - ft1000_write_dpram32(ft1000dev, 0, commandbuf, size); + ret = ft1000_write_dpram32(ft1000dev, 0, commandbuf, size); + if (ret) + return ret; usleep_range(900, 1100); - ft1000_write_register(ft1000dev, FT1000_DB_DPRAM_TX, + ret = ft1000_write_register(ft1000dev, FT1000_DB_DPRAM_TX, FT1000_REG_DOORBELL); + if (ret) + return ret; usleep_range(900, 1100); - ft1000_read_register(ft1000dev, &temp, FT1000_REG_DOORBELL); + ret = ft1000_read_register(ft1000dev, &temp, FT1000_REG_DOORBELL); #if 0 if ((temp & 0x0100) == 0) DEBUG("card_send_command: Message sent\n"); #endif - + return ret; } /* load or reload the DSP */ @@ -1375,8 +1384,10 @@ static int ft1000_proc_drvmsg(struct ft1000_usb *dev, u16 size) *pmsg++ = convert.wrd; *pmsg++ = htons(info->DrvErrNum); - card_send_command(dev, (unsigned char *)&tempbuffer[0], + status = card_send_command(dev, (unsigned char *)&tempbuffer[0], (u16)(0x0012 + PSEUDOSZ)); + if (status) + goto out; info->DrvErrNum = 0; } dev->DrvMsgPend = 0; diff --git a/drivers/staging/ft1000/ft1000-usb/ft1000_usb.h b/drivers/staging/ft1000/ft1000-usb/ft1000_usb.h index 2d4b02e..464e5ab 100644 --- a/drivers/staging/ft1000/ft1000-usb/ft1000_usb.h +++ b/drivers/staging/ft1000/ft1000-usb/ft1000_usb.h @@ -136,7 +136,7 @@ extern spinlock_t free_buff_lock; int ft1000_create_dev(struct ft1000_usb *dev); void ft1000_destroy_dev(struct net_device *dev); -extern void card_send_command(struct ft1000_usb *ft1000dev, +extern int card_send_command(struct ft1000_usb *ft1000dev, void *ptempbuffer, int size); struct dpram_blk *ft1000_get_buffer(struct list_head *bufflist); -- 1.8.3.2