Re: [PATCH] net/mlx5e: always initialize frag->last_in_page
From: Tariq Toukan <hidden>
Date: 2019-08-01 07:46:14
Also in:
lkml
On 7/31/2019 10:02 PM, Qian Cai wrote:
quoted hunk ↗ jump to hunk
The commit 069d11465a80 ("net/mlx5e: RX, Enhance legacy Receive Queue memory scheme") introduced an undefined behaviour below due to "frag->last_in_page" is only initialized in mlx5e_init_frags_partition() when, if (next_frag.offset + frag_info[f].frag_stride > PAGE_SIZE) or after bailed out the loop, for (i = 0; i < mlx5_wq_cyc_get_size(&rq->wqe.wq); i++) As the result, there could be some "frag" have uninitialized value of "last_in_page". Later, get_frag() obtains those "frag" and check "rag->last_in_page" in mlx5e_put_rx_frag() and triggers the error during boot. Fix it by always initializing "frag->last_in_page" to "false" in mlx5e_init_frags_partition(). UBSAN: Undefined behaviour in drivers/net/ethernet/mellanox/mlx5/core/en_rx.c:325:12 load of value 170 is not a valid value for type 'bool' (aka '_Bool') Call trace: dump_backtrace+0x0/0x264 show_stack+0x20/0x2c dump_stack+0xb0/0x104 __ubsan_handle_load_invalid_value+0x104/0x128 mlx5e_handle_rx_cqe+0x8e8/0x12cc [mlx5_core] mlx5e_poll_rx_cq+0xca8/0x1a94 [mlx5_core] mlx5e_napi_poll+0x17c/0xa30 [mlx5_core] net_rx_action+0x248/0x940 __do_softirq+0x350/0x7b8 irq_exit+0x200/0x26c __handle_domain_irq+0xc8/0x128 gic_handle_irq+0x138/0x228 el1_irq+0xb8/0x140 arch_cpu_idle+0x1a4/0x348 do_idle+0x114/0x1b0 cpu_startup_entry+0x24/0x28 rest_init+0x1ac/0x1dc arch_call_rest_init+0x10/0x18 start_kernel+0x4d4/0x57c Fixes: 069d11465a80 ("net/mlx5e: RX, Enhance legacy Receive Queue memory scheme") Signed-off-by: Qian Cai <redacted> --- drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 1 + 1 file changed, 1 insertion(+)diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 47eea6b3a1c3..96f5110a9b43 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c@@ -336,6 +336,7 @@ static void mlx5e_init_frags_partition(struct mlx5e_rq *rq) next_frag.di = &rq->wqe.di[0]; next_frag.offset = 0; + next_frag.last_in_page = false; prev = NULL; for (i = 0; i < mlx5_wq_cyc_get_size(&rq->wqe.wq); i++) {
Thanks Qian. Please zero-init the whole struct instead:
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 1f433a06e637..55f4f5cc1d8f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c@@ -312,11 +312,10 @@ static inline u64 mlx5e_get_mpwqe_offset(struct mlx5e_rq *rq, u16 wqe_ix)
static void mlx5e_init_frags_partition(struct mlx5e_rq *rq)
{
- struct mlx5e_wqe_frag_info next_frag, *prev;
+ struct mlx5e_wqe_frag_info next_frag = {}, *prev;
int i;
next_frag.di = &rq->wqe.di[0];
- next_frag.offset = 0;
prev = NULL;
for (i = 0; i < mlx5_wq_cyc_get_size(&rq->wqe.wq); i++) {
Thanks,
Tariq