diff options
| author | Steven Rostedt (Google) <[email protected]> | 2024-01-31 13:49:19 -0500 |
|---|---|---|
| committer | Steven Rostedt (Google) <[email protected]> | 2024-01-31 14:15:47 -0500 |
| commit | d81786f53aec14fd4d56263145a0635afbc64617 (patch) | |
| tree | 3a8e0d8fde941c440ec21ce60e6e4319dbc1b583 | |
| parent | 66bbea9ed6446b8471d365a22734dc00556c4785 (diff) | |
tracefs: Zero out the tracefs_inode when allocating it
eventfs uses the tracefs_inode and assumes that it's already initialized
to zero. That is, it doesn't set fields to zero (like ti->private) after
getting its tracefs_inode. This causes bugs due to stale values.
Just initialize the entire structure to zero on allocation so there isn't
any more surprises.
This is a partial fix to access to ti->private. The assignment still needs
to be made before the dentry is instantiated.
Link: https://lore.kernel.org/linux-trace-kernel/[email protected]
Cc: [email protected]
Cc: Masami Hiramatsu <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Ajay Kaher <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-lkp/[email protected]
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
| -rw-r--r-- | fs/tracefs/inode.c | 6 | ||||
| -rw-r--r-- | fs/tracefs/internal.h | 3 |
2 files changed, 6 insertions, 3 deletions
diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index e1b172c0e091..888e42087847 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -38,8 +38,6 @@ static struct inode *tracefs_alloc_inode(struct super_block *sb) if (!ti) return NULL; - ti->flags = 0; - return &ti->vfs_inode; } @@ -779,7 +777,11 @@ static void init_once(void *foo) { struct tracefs_inode *ti = (struct tracefs_inode *) foo; + /* inode_init_once() calls memset() on the vfs_inode portion */ inode_init_once(&ti->vfs_inode); + + /* Zero out the rest */ + memset_after(ti, 0, vfs_inode); } static int __init tracefs_init(void) diff --git a/fs/tracefs/internal.h b/fs/tracefs/internal.h index 91c2bf0b91d9..7d84349ade87 100644 --- a/fs/tracefs/internal.h +++ b/fs/tracefs/internal.h @@ -11,9 +11,10 @@ enum { }; struct tracefs_inode { + struct inode vfs_inode; + /* The below gets initialized with memset_after(ti, 0, vfs_inode) */ unsigned long flags; void *private; - struct inode vfs_inode; }; /* |