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| author | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-11-13 17:03:28 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-11-14 14:24:45 -0200 |
| commit | 494264379d186bf806613d27aafb7d88d42f4212 (patch) | |
| tree | 681aeb1444d7e1b2d994d5045644a0c8ec44e342 | |
| parent | 81cb5c4f7fbe6971d9c61401bc47193290fd59b7 (diff) | |
| download | linux-494264379d186bf806613d27aafb7d88d42f4212.tar.gz linux-494264379d186bf806613d27aafb7d88d42f4212.tar.bz2 linux-494264379d186bf806613d27aafb7d88d42f4212.zip | |
V4L/DVB (9621): Avoid writing outside shadow.bytes[] array
There were no check about the limits of shadow.bytes array. This offers
a risk of writing values outside the limits, overriding other data
areas.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | drivers/media/video/tvaudio.c | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/drivers/media/video/tvaudio.c b/drivers/media/video/tvaudio.c index 5ec369d54e6e..55b39b9a33d9 100644 --- a/drivers/media/video/tvaudio.c +++ b/drivers/media/video/tvaudio.c @@ -154,7 +154,7 @@ static int chip_write(struct CHIPSTATE *chip, int subaddr, int val) { unsigned char buffer[2]; - if (-1 == subaddr) { + if (subaddr < 0) { v4l_dbg(1, debug, chip->c, "%s: chip_write: 0x%x\n", chip->c->name, val); chip->shadow.bytes[1] = val; @@ -165,6 +165,13 @@ static int chip_write(struct CHIPSTATE *chip, int subaddr, int val) return -1; } } else { + if (subaddr + 1 >= ARRAY_SIZE(chip->shadow.bytes)) { + v4l_info(chip->c, + "Tried to access a non-existent register: %d\n", + subaddr); + return -EINVAL; + } + v4l_dbg(1, debug, chip->c, "%s: chip_write: reg%d=0x%x\n", chip->c->name, subaddr, val); chip->shadow.bytes[subaddr+1] = val; @@ -179,12 +186,20 @@ static int chip_write(struct CHIPSTATE *chip, int subaddr, int val) return 0; } -static int chip_write_masked(struct CHIPSTATE *chip, int subaddr, int val, int mask) +static int chip_write_masked(struct CHIPSTATE *chip, + int subaddr, int val, int mask) { if (mask != 0) { - if (-1 == subaddr) { + if (subaddr < 0) { val = (chip->shadow.bytes[1] & ~mask) | (val & mask); } else { + if (subaddr + 1 >= ARRAY_SIZE(chip->shadow.bytes)) { + v4l_info(chip->c, + "Tried to access a non-existent register: %d\n", + subaddr); + return -EINVAL; + } + val = (chip->shadow.bytes[subaddr+1] & ~mask) | (val & mask); } } @@ -230,6 +245,15 @@ static int chip_cmd(struct CHIPSTATE *chip, char *name, audiocmd *cmd) if (0 == cmd->count) return 0; + if (cmd->count + cmd->bytes[0] - 1 >= ARRAY_SIZE(chip->shadow.bytes)) { + v4l_info(chip->c, + "Tried to access a non-existent register range: %d to %d\n", + cmd->bytes[0] + 1, cmd->bytes[0] + cmd->count - 1); + return -EINVAL; + } + + /* FIXME: it seems that the shadow bytes are wrong bellow !*/ + /* update our shadow register set; print bytes if (debug > 0) */ v4l_dbg(1, debug, chip->c, "%s: chip_cmd(%s): reg=%d, data:", chip->c->name, name,cmd->bytes[0]); |