[PATCH] net/mlx5: fix a -Wstringop-truncation warning
From: Qian Cai
Date: Fri Aug 23 2019 - 15:56:47 EST
In file included from ./arch/powerpc/include/asm/paca.h:15,
from ./arch/powerpc/include/asm/current.h:13,
from ./include/linux/thread_info.h:21,
from ./include/asm-generic/preempt.h:5,
from ./arch/powerpc/include/generated/asm/preempt.h:1,
from ./include/linux/preempt.h:78,
from ./include/linux/spinlock.h:51,
from ./include/linux/wait.h:9,
from ./include/linux/completion.h:12,
from ./include/linux/mlx5/driver.h:37,
from
drivers/net/ethernet/mellanox/mlx5/core/lib/eq.h:6,
from
drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c:33:
In function 'strncpy',
inlined from 'mlx5_fw_tracer_save_trace' at
drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c:549:2,
inlined from 'mlx5_tracer_print_trace' at
drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c:574:2:
./include/linux/string.h:305:9: warning: '__builtin_strncpy' output may
be truncated copying 256 bytes from a string of length 511
[-Wstringop-truncation]
return __builtin_strncpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix it by using the new strscpy_pad() since the commit 458a3bf82df4
("lib/string: Add strscpy_pad() function") which will always
NUL-terminate the string, and avoid possibly leak data through the ring
buffer where non-admin account might enable these events through perf.
Fixes: fd1483fe1f9f ("net/mlx5: Add support for FW reporter dump")
Signed-off-by: Qian Cai <cai@xxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
index 8a4930c8bf62..2011eaf15cc5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
@@ -546,7 +546,7 @@ static void mlx5_fw_tracer_save_trace(struct mlx5_fw_tracer *tracer,
trace_data->timestamp = timestamp;
trace_data->lost = lost;
trace_data->event_id = event_id;
- strncpy(trace_data->msg, msg, TRACE_STR_MSG);
+ strscpy_pad(trace_data->msg, msg, TRACE_STR_MSG);
tracer->st_arr.saved_traces_index =
(tracer->st_arr.saved_traces_index + 1) & (SAVED_TRACES_NUM - 1);
--
1.8.3.1