[PATCH][next] bcachefs: Fix multiple -Warray-bounds warnings

[PATCH][next] bcachefs: Fix multiple -Warray-bounds warnings

[Gustavo A. R. Silva]

Transform zero-length array `entries` into a proper flexible-array
member in `struct journal_seq_blacklist_table`; and fix the following
-Warray-bounds warnings:

fs/bcachefs/journal_seq_blacklist.c:148:26: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:150:30: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:154:27: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:176:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:177:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:297:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:298:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
fs/bcachefs/journal_seq_blacklist.c:300:31: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]

This results in no differences in binary output.

This helps with the ongoing efforts to globally enable -Warray-bounds.

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 fs/bcachefs/bcachefs.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index 53ffa88cae16..e42f2977f7aa 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -612,7 +612,7 @@ struct journal_seq_blacklist_table {
 		u64		start;
 		u64		end;
 		bool		dirty;
-	}			entries[0];
+	}			entries[];
 };
 
 struct journal_keys {
-- 
2.34.1

Re: [PATCH][next] bcachefs: Fix multiple -Warray-bounds warnings

[Kees Cook]

On Mon, Nov 06, 2023 at 03:40:22PM -0600, Gustavo A. R. Silva wrote:
> Transform zero-length array `entries` into a proper flexible-array
> member in `struct journal_seq_blacklist_table`; and fix the following
> -Warray-bounds warnings:
> 
> fs/bcachefs/journal_seq_blacklist.c:148:26: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:150:30: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:154:27: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:176:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:177:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:297:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:298:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:300:31: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> 
> This results in no differences in binary output.
> 
> This helps with the ongoing efforts to globally enable -Warray-bounds.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks; that looks right to me.

-Kees

-- 
Kees Cook

Re: [PATCH][next] bcachefs: Fix multiple -Warray-bounds warnings

[Kent Overstreet]

On Mon, Nov 06, 2023 at 03:40:22PM -0600, Gustavo A. R. Silva wrote:
> Transform zero-length array `entries` into a proper flexible-array
> member in `struct journal_seq_blacklist_table`; and fix the following
> -Warray-bounds warnings:
> 
> fs/bcachefs/journal_seq_blacklist.c:148:26: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:150:30: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:154:27: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:176:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:177:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:297:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:298:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> fs/bcachefs/journal_seq_blacklist.c:300:31: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=]
> 
> This results in no differences in binary output.
> 
> This helps with the ongoing efforts to globally enable -Warray-bounds.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks, applied