Re: [PATCH] scsi: target: tcmu: Annotate struct tcmu_tmr with __counted_by

From: Bodo Stroesser
Date: Sun Sep 24 2023 - 13:06:40 EST


On 22.09.23 19:53, Kees Cook wrote:
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct tcmu_tmr.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Bodo Stroesser <bostroesser@xxxxxxxxx>
Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Cc: linux-scsi@xxxxxxxxxxxxxxx
Cc: target-devel@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/target/target_core_user.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 22cc6cac0ba2..7eb94894bd68 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -201,7 +201,7 @@ struct tcmu_tmr {
uint8_t tmr_type;
uint32_t tmr_cmd_cnt;
- int16_t tmr_cmd_ids[];
+ int16_t tmr_cmd_ids[] __counted_by(tmr_cmd_cnt);
};
/*

Reviewed-by: Bodo Stroesser <bostroesser@xxxxxxxxx>

Thank you,
Bodo