| Message ID | c4bc83220906091531h20677733kd993ed50c0bc74ec@mail.gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On 06/10/2009 01:31 AM, Jan Nikitenko wrote: > This patch fixes stack corruption bug present in af9015_eeprom_dump(): > the buffer buf is one byte smaller than required - there is 4 chars > for address prefix, 16*3 chars for dump of 16 eeprom bytes per line > and 1 byte for zero ending the string required, i.e. 53 bytes, but > only 52 are provided. > The one byte missing in stack based buffer buf causes following oops > on MIPS little endian platform, because i2c_adap pointer in > af9015_af9013_frontend_attach() is corrupted by inlined function > af9015_eeprom_dump(): > Signed-off-by: Jan Nikitenko<jan.nikitenko@gmail.com> Acked-by: Antti Palosaari <crope@iki.fi> regards Antti
diff -r cff06234b725 linux/drivers/media/dvb/dvb-usb/af9015.c --- a/linux/drivers/media/dvb/dvb-usb/af9015.c Sun May 31 23:07:01 2009 +0300 +++ b/linux/drivers/media/dvb/dvb-usb/af9015.c Wed Jun 10 00:25:53 2009 +0200 @@ -541,7 +541,7 @@ /* dump eeprom */ static int af9015_eeprom_dump(struct dvb_usb_device *d) { - char buf[52], buf2[4]; + char buf[4+3*16+1], buf2[4]; u8 reg, val; for (reg = 0; ; reg++) {
This patch fixes stack corruption bug present in af9015_eeprom_dump(): the buffer buf is one byte smaller than required - there is 4 chars for address prefix, 16*3 chars for dump of 16 eeprom bytes per line and 1 byte for zero ending the string required, i.e. 53 bytes, but only 52 are provided. The one byte missing in stack based buffer buf causes following oops on MIPS little endian platform, because i2c_adap pointer in af9015_af9013_frontend_attach() is corrupted by inlined function af9015_eeprom_dump(): CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 803a4488, ra == c049a1c8 Oops[#1]: Cpu 0 $ 0 : 00000000 10003c00 00000000 803a4468 $ 4 : 8f17c600 8f067b30 00000002 00000038 $ 8 : 00000001 8faf3e98 11da000d 09010002 $12 : 00000000 00000000 00000000 0000000a $16 : 8f17c600 8f067b68 8faf3c00 8f067c04 $20 : 8f067b9c 00000100 8f067bf0 80104100 $24 : 00000000 2aba9fb0 $28 : 8f066000 8f067af0 802cbc48 c049a1c8 Hi : 00000000 Lo : 00000000 epc : 803a4488 i2c_transfer+0x20/0x104 Not tainted ra : c049a1c8 af9013_read_reg+0x78/0xc4 [af9013] Status: 10003c03 KERNEL EXL IE Cause : 00808008 BadVA : 00000000 PrId : 03030200 (Au1550) Modules linked in: af9013 dvb_usb_af9015(+) dvb_usb dvb_core firmware_class i2c_au1550 au1550_spi Process modprobe (pid: 2757, threadinfo=8f066000, task=8fade098, tls=2aad6470) Stack : c049f5e0 80163090 805ba880 00000100 8f067bf0 0000d733 8f067b68 8faf3c00 8f067c04 c049a1c8 80163bc0 8056a630 8f067b40 80163224 80569fc8 8f0033d7 00000038 80140003 8f067b2c 00010038 c0420001 8f067b28 c049f5e0 00000004 00000004 c049a524 c049d5a8 c049d5a8 00000000 803a6700 00000000 8f17c600 c042a7a4 8f17c600 c042a7a4 c049c924 00000000 00000000 00000002 613a6c00 ... Call Trace: [<803a4488>] i2c_transfer+0x20/0x104 [<c049a1c8>] af9013_read_reg+0x78/0xc4 [af9013] [<c049a524>] af9013_read_reg_bits+0x2c/0x70 [af9013] [<c049c924>] af9013_attach+0x98/0x65c [af9013] [<c04257bc>] af9015_af9013_frontend_attach+0x214/0x67c [dvb_usb_af9015] [<c03e2428>] dvb_usb_adapter_frontend_init+0x20/0x12c [dvb_usb] [<c03e1ad8>] dvb_usb_device_init+0x374/0x6b0 [dvb_usb] [<c0426120>] af9015_usb_probe+0x4fc/0xfcc [dvb_usb_af9015] [<80381024>] usb_probe_interface+0xbc/0x218 [<803227fc>] driver_probe_device+0x12c/0x30c [<80322a80>] __driver_attach+0xa4/0xac [<80321ed0>] bus_for_each_dev+0x60/0xd0 [<8032162c>] bus_add_driver+0x1e8/0x2a8 [<80322cdc>] driver_register+0x7c/0x17c [<80380d30>] usb_register_driver+0xa0/0x12c [<c042e030>] af9015_usb_module_init+0x30/0x6c [dvb_usb_af9015] [<8010d2a4>] __kprobes_text_end+0x3c/0x1f4 [<80167150>] sys_init_module+0xb8/0x1cc [<80102370>] stack_done+0x20/0x3c Code: afb10018 7000003f 00808021 <8c430000> 7000003f 1060002d 00c09021 8f830014 3c02efff Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com> --- linux/drivers/media/dvb/dvb-usb/af9015.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html