6.1-stable review patch. If anyone has any objections, please let me know.
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From: Ekansh Gupta quic_ekangupt@quicinc.com
[ Upstream commit a2cb9cd6a3949a3804ad9fd7da234892ce6719ec ]
Scatterlist table is obtained during map create request and the same table is used for DMA mapping unmap. In case there is any failure while getting the sg_table, ERR_PTR is returned instead of sg_table.
When the map is getting freed, there is only a non-NULL check of sg_table which will also be true in case failure was returned instead of sg_table. This would result in improper unmap request. Add proper check before setting map table to avoid bad unmap request.
Fixes: c68cfb718c8f ("misc: fastrpc: Add support for context Invoke method") Cc: stable 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/20230811115643.38578-3-srinivas.kandagatla@linaro.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/misc/fastrpc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index e9291694922bc..4c51d216f3d43 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -711,6 +711,7 @@ static int fastrpc_map_create(struct fastrpc_user *fl, int fd, { struct fastrpc_session_ctx *sess = fl->sctx; struct fastrpc_map *map = NULL; + struct sg_table *table; int err = 0;
if (!fastrpc_map_lookup(fl, fd, ppmap, true)) @@ -736,11 +737,12 @@ static int fastrpc_map_create(struct fastrpc_user *fl, int fd, goto attach_err; }
- map->table = dma_buf_map_attachment_unlocked(map->attach, DMA_BIDIRECTIONAL); - if (IS_ERR(map->table)) { - err = PTR_ERR(map->table); + table = dma_buf_map_attachment_unlocked(map->attach, DMA_BIDIRECTIONAL); + if (IS_ERR(table)) { + err = PTR_ERR(table); goto map_err; } + map->table = table;
map->phys = sg_dma_address(map->table->sgl); map->phys += ((u64)fl->sctx->sid << 32);