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author | Thanassis Avgerinos <thanassis.avgerinos@gmail.com> | 2024-04-17 18:30:02 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-05-17 12:43:54 +0300 |
commit | 7b8c7bd2296e95b38a6ff346242356a2e7190239 (patch) | |
tree | fb5ad00ca471da16111c01095b1a2c6b324609fe | |
parent | e44d406388f8deddaac656134b63ef50ae2fa0a8 (diff) | |
download | linux-7b8c7bd2296e95b38a6ff346242356a2e7190239.tar.xz |
firewire: nosy: ensure user_length is taken into account when fetching packet contents
commit 38762a0763c10c24a4915feee722d7aa6e73eb98 upstream.
Ensure that packet_buffer_get respects the user_length provided. If
the length of the head packet exceeds the user_length, packet_buffer_get
will now return 0 to signify to the user that no data were read
and a larger buffer size is required. Helps prevent user space overflows.
Signed-off-by: Thanassis Avgerinos <thanassis.avgerinos@gmail.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/firewire/nosy.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/firewire/nosy.c b/drivers/firewire/nosy.c index 9ee747a85ee4..8bb609085911 100644 --- a/drivers/firewire/nosy.c +++ b/drivers/firewire/nosy.c @@ -148,10 +148,12 @@ packet_buffer_get(struct client *client, char __user *data, size_t user_length) if (atomic_read(&buffer->size) == 0) return -ENODEV; - /* FIXME: Check length <= user_length. */ + length = buffer->head->length; + + if (length > user_length) + return 0; end = buffer->data + buffer->capacity; - length = buffer->head->length; if (&buffer->head->data[length] < end) { if (copy_to_user(data, buffer->head->data, length)) |