[SRU][J/N/P][PATCH 2/2] crypto: af_alg - Fix incorrect boolean values in af_alg_ctx

[Ian Whitfield]

From: Eric Biggers <ebiggers at kernel.org>

Commit 1b34cbbf4f01 ("crypto: af_alg - Disallow concurrent writes in
af_alg_sendmsg") changed some fields from bool to 1-bit bitfields of
type u32.

However, some assignments to these fields, specifically 'more' and
'merge', assign values greater than 1.  These relied on C's implicit
conversion to bool, such that zero becomes false and nonzero becomes
true.

With a 1-bit bitfields of type u32 instead, mod 2 of the value is taken
instead, resulting in 0 being assigned in some cases when 1 was intended.

Fix this by restoring the bool type.

Fixes: 1b34cbbf4f01 ("crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg")
Cc: stable at vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers at kernel.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
(cherry picked from commit d0ca0df179c4b21e2a6c4a4fb637aa8fa14575cb)
CVE-2025-39964
Signed-off-by: Ian Whitfield <ian.whitfield at canonical.com>
---
 include/crypto/if_alg.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 0c70f3a55575..107b797c33ec 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -152,7 +152,7 @@ struct af_alg_ctx {
 	size_t used;
 	atomic_t rcvused;
 
-	u32		more:1,
+	bool		more:1,
 			merge:1,
 			enc:1,
 			write:1,
-- 
2.43.0