Skip to contentSkip to conversation

i3c: master: cdns: Annotate struct cdns_i3c_xfer with __counted_by

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

Subsystems (2)
I3C I3C driver for cadence I3C master IP
lore
Share & tools
lore

Kees Cook

author
#0 lore raw

PATCH 1/1 i3c: master: cdns: Annotate struct cdns_i3c_xfer 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 cdns_i3c_xfer.

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

Cc "Przemysław Gaj" <[email protected]>
Cc Alexandre Belloni <[email protected]>
Cc [email protected]
Signed-off-by Kees Cook <[email protected]>
---
 drivers/i3c/master/i3c-master-cdns.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/i3c/master/i3c-master-cdns.c +1 -1
index 49551db71bc9..97c1010956a0 100644
@@ -387,7 +387,7 @@ struct cdns_i3c_xfer {
 	struct completion comp;
 	int ret;
 	unsigned int ncmds;
-	struct cdns_i3c_cmd cmds[];
+	struct cdns_i3c_cmd cmds[] __counted_by(ncmds);
 };
 
 struct cdns_i3c_data {
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 8 lines

As found with Coccinelle[1], add __counted_by for struct cdns_i3c_xfer.

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

Cc "Przemysław Gaj" <[email protected]>
Cc Alexandre Belloni <[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
---
  drivers/i3c/master/i3c-master-cdns.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
drivers/i3c/master/i3c-master-cdns.c +1 -1
index 49551db71bc9..97c1010956a0 100644
@@ -387,7 +387,7 @@ struct cdns_i3c_xfer {
  	struct completion comp;
  	int ret;
  	unsigned int ncmds;
-	struct cdns_i3c_cmd cmds[];
+	struct cdns_i3c_cmd cmds[] __counted_by(ncmds);
  };
 
  struct cdns_i3c_data {
maintainer Applied
#2 lore raw
In reply to Kees Cook
Quoted 9 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).

As found with Coccinelle[1], add __counted_by for struct cdns_i3c_xfer.

[...]

Applied, thanks!

[1/1] i3c: master: cdns: Annotate struct cdns_i3c_xfer with __counted_by

      commit: 49f33846efc079eb94b044bf897e90909fd3aa11

Best regards,

Signature · 3 lines
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com