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libata: Annotate struct ata_cpr_log with __counted_by

PATCH Applied Kees Cook 3 participants 3 messages Sep 22, 2023 – Sep 25, 2023 libata

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Kees Cook

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#0 lore raw

PATCH 1/1 libata: Annotate struct ata_cpr_log with __counted_by

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 ata_cpr_log.

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

Cc Damien Le Moal <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>
---
 include/linux/libata.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
include/linux/libata.h +1 -1
index 3c17a5053f00..f91e8e7f1c00 100644
@@ -656,7 +656,7 @@ struct ata_cpr {
 
 struct ata_cpr_log {
 	u8			nr_cpr;
-	struct ata_cpr		cpr[];
+	struct ata_cpr		cpr[] __counted_by(nr_cpr);
 };
 
 struct ata_device {
Signature · 1 line
2.34.1
Reviewed-by on v1 1/1
#1 lore raw
Quoted 6 lines · Kees Cook

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).

Quoted 7 lines

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

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

Cc Damien Le Moal <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>
Reviewed-by Gustavo A. R. Silva <[email protected]>

Thanks

Signature · 1 line
Gustavo
Quoted 17 lines
---
  include/linux/libata.h | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
include/linux/libata.h +1 -1
index 3c17a5053f00..f91e8e7f1c00 100644
@@ -656,7 +656,7 @@ struct ata_cpr {
 
  struct ata_cpr_log {
  	u8			nr_cpr;
-	struct ata_cpr		cpr[];
+	struct ata_cpr		cpr[] __counted_by(nr_cpr);
  };
 
  struct ata_device {
maintainer Applied
#2 lore raw
In reply to Kees Cook
Quoted 6 lines · Kees Cook

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).

Quoted 7 lines

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

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

Cc Damien Le Moal <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>

Applied to for-6.7. Thanks !

Signature · 2 lines
Damien Le Moal
Western Digital Research