linux-kernel - [PATCH] eventfs: Use ERR_CAST() in eventfs_create_events

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20231018-ftrace-fix-clang-randstruct-v1-1-338cb214abfb@kernel.org>
Date:   Wed, 18 Oct 2023 11:10:31 -0700
From:   Nathan Chancellor <nathan@...nel.org>
To:     rostedt@...dmis.org, mhiramat@...nel.org
Cc:     keescook@...omium.org, ndesaulniers@...gle.com, trix@...hat.com,
        linux-kernel@...r.kernel.org, linux-trace-kernel@...r.kernel.org,
        llvm@...ts.linux.dev, patches@...ts.linux.dev,
        Nathan Chancellor <nathan@...nel.org>
Subject: [PATCH] eventfs: Use ERR_CAST() in eventfs_create_events_dir()

When building with clang and CONFIG_RANDSTRUCT_FULL=y, there is an error
due to a cast in eventfs_create_events_dir():

  fs/tracefs/event_inode.c:734:10: error: casting from randomized structure pointer type 'struct dentry *' to 'struct eventfs_inode *'
    734 |                 return (struct eventfs_inode *)dentry;
        |                        ^
  1 error generated.

Use the ERR_CAST() function to resolve the error, as it was designed for
this exact situation (casting an error pointer to another type).

Closes: https://github.com/ClangBuiltLinux/linux/issues/1947
Fixes: 5790b1fb3d67 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Signed-off-by: Nathan Chancellor <nathan@...nel.org>
---
 fs/tracefs/event_inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c
index 1ccd100bc565..9f19b6608954 100644
--- a/fs/tracefs/event_inode.c
+++ b/fs/tracefs/event_inode.c
@@ -731,7 +731,7 @@ struct eventfs_inode *eventfs_create_events_dir(const char *name, struct dentry
 		return NULL;
 
 	if (IS_ERR(dentry))
-		return (struct eventfs_inode *)dentry;
+		return ERR_CAST(dentry);
 
 	ei = kzalloc(sizeof(*ei), GFP_KERNEL);
 	if (!ei)

---
base-commit: 5ddd8baa4857709b4e5d84b376d735152851955b
change-id: 20231018-ftrace-fix-clang-randstruct-0cb6899523ac

Best regards,
-- 
Nathan Chancellor <nathan@...nel.org>