misc: fastrpc: Fix copy buffer page size

For non-registered buffer, fastrpc driver copies the buffer and
pass it to the remote subsystem. There is a problem with current
implementation of page size calculation which is not considering
the offset in the calculation. This might lead to passing of
improper and out-of-bounds page size which could result in
memory issue. Calculate page start and page end using the offset
adjusted address instead of absolute address.

Fixes: 02b45b47fb ("misc: fastrpc: fix remote page size calculation")
Cc: stable@kernel.org
Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20250110134239.123603-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ekansh Gupta
2025-01-10 13:42:39 +00:00
committed by Greg Kroah-Hartman
parent 6ca4ea1f88
commit e966eae727

View File

@@ -1019,8 +1019,8 @@ static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
(pkt_size - rlen);
pages[i].addr = pages[i].addr & PAGE_MASK;
pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
pg_start = (rpra[i].buf.pv & PAGE_MASK) >> PAGE_SHIFT;
pg_end = ((rpra[i].buf.pv + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
args = args + mlen;
rlen -= mlen;