The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 0dfc852b6fe3cbecbea67332a0dce2bebeba540d # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023122844-pellet-sharpie-7d33@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: 0dfc852b6fe3 ("eventfs: Have event files and directories default to parent uid and gid") 28e12c09f5aa ("eventfs: Save ownership and mode") db3a397209b0 ("eventfs: Have a free_ei() that just frees the eventfs_inode") 5790b1fb3d67 ("eventfs: Remove eventfs_file and just use eventfs_inode") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 0dfc852b6fe3cbecbea67332a0dce2bebeba540d Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx> Date: Wed, 20 Dec 2023 10:50:17 -0500 Subject: [PATCH] eventfs: Have event files and directories default to parent uid and gid Dongliang reported: I found that in the latest version, the nodes of tracefs have been changed to dynamically created. This has caused me to encounter a problem where the gid I specified in the mounting parameters cannot apply to all files, as in the following situation: /data/tmp/events # mount | grep tracefs tracefs on /data/tmp type tracefs (rw,seclabel,relatime,gid=3012) gid 3012 = readtracefs /data/tmp # ls -lh total 0 -r--r----- 1 root readtracefs 0 1970-01-01 08:00 README -r--r----- 1 root readtracefs 0 1970-01-01 08:00 available_events ums9621_1h10:/data/tmp/events # ls -lh total 0 drwxr-xr-x 2 root root 0 2023-12-19 00:56 alarmtimer drwxr-xr-x 2 root root 0 2023-12-19 00:56 asoc It will prevent certain applications from accessing tracefs properly, I try to avoid this issue by making the following modifications. To fix this, have the files created default to taking the ownership of the parent dentry unless the ownership was previously set by the user. Link: https://lore.kernel.org/linux-trace-kernel/1703063706-30539-1-git-send-email-dongliang.cui@xxxxxxxxxx/ Link: https://lore.kernel.org/linux-trace-kernel/20231220105017.1489d790@xxxxxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> Cc: Hongyu Jin <hongyu.jin@xxxxxxxxxx> Fixes: 28e12c09f5aa0 ("eventfs: Save ownership and mode") Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Reported-by: Dongliang Cui <cuidongliang390@xxxxxxxxx> Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 43e237864a42..2ccc849a5bda 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -148,7 +148,8 @@ static const struct file_operations eventfs_file_operations = { .release = eventfs_release, }; -static void update_inode_attr(struct inode *inode, struct eventfs_attr *attr, umode_t mode) +static void update_inode_attr(struct dentry *dentry, struct inode *inode, + struct eventfs_attr *attr, umode_t mode) { if (!attr) { inode->i_mode = mode; @@ -162,9 +163,13 @@ static void update_inode_attr(struct inode *inode, struct eventfs_attr *attr, um if (attr->mode & EVENTFS_SAVE_UID) inode->i_uid = attr->uid; + else + inode->i_uid = d_inode(dentry->d_parent)->i_uid; if (attr->mode & EVENTFS_SAVE_GID) inode->i_gid = attr->gid; + else + inode->i_gid = d_inode(dentry->d_parent)->i_gid; } /** @@ -206,7 +211,7 @@ static struct dentry *create_file(const char *name, umode_t mode, return eventfs_failed_creating(dentry); /* If the user updated the directory's attributes, use them */ - update_inode_attr(inode, attr, mode); + update_inode_attr(dentry, inode, attr, mode); inode->i_op = &eventfs_file_inode_operations; inode->i_fop = fop; @@ -242,7 +247,8 @@ static struct dentry *create_dir(struct eventfs_inode *ei, struct dentry *parent return eventfs_failed_creating(dentry); /* If the user updated the directory's attributes, use them */ - update_inode_attr(inode, &ei->attr, S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO); + update_inode_attr(dentry, inode, &ei->attr, + S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO); inode->i_op = &eventfs_root_dir_inode_operations; inode->i_fop = &eventfs_file_operations;
