6.1-stable review patch. If anyone has any objections, please let me know.
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From: wangzijie wangzijie1@honor.com
[ Upstream commit 0ce9398aa0830f15f92bbed73853f9861c3e74ff ]
Commit 2ce3d282bd50 ("proc: fix missing pde_set_flags() for net proc files") missed a key part in the definition of proc_dir_entry:
union { const struct proc_ops *proc_ops; const struct file_operations *proc_dir_ops; };
So dereference of ->proc_ops assumes it is a proc_ops structure results in type confusion and make NULL check for 'proc_ops' not work for proc dir.
Add !S_ISDIR(dp->mode) test before calling pde_set_flags() to fix it.
Link: https://lkml.kernel.org/r/20250904135715.3972782-1-wangzijie1@honor.com Fixes: 2ce3d282bd50 ("proc: fix missing pde_set_flags() for net proc files") Signed-off-by: wangzijie wangzijie1@honor.com Reported-by: Brad Spengler spender@grsecurity.net Closes: https://lore.kernel.org/all/20250903065758.3678537-1-wangzijie1@honor.com/ Cc: Alexey Dobriyan adobriyan@gmail.com Cc: Al Viro viro@zeniv.linux.org.uk Cc: Christian Brauner brauner@kernel.org Cc: Jiri Slaby jirislaby@kernel.org Cc: Stefano Brivio sbrivio@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/proc/generic.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/proc/generic.c b/fs/proc/generic.c index c96c884208a98..21820c729b4bd 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -389,7 +389,8 @@ struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, if (proc_alloc_inum(&dp->low_ino)) goto out_free_entry;
- pde_set_flags(dp); + if (!S_ISDIR(dp->mode)) + pde_set_flags(dp);
write_lock(&proc_subdir_lock); dp->parent = dir;