From d0f102fce372e57970bd1debbee1dbdd0152cf6d Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Mon, 1 Jun 2026 15:56:50 +0200 Subject: initramfs: use scoped_with_init_fs() for rootfs unpacking MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Extract the initramfs unpacking code into a separate unpack_initramfs() function and wrap its invocation from do_populate_rootfs() with scoped_with_init_fs(). This ensures all file operations during initramfs unpacking (including filp_open() calls in do_name() and populate_initrd_image()) happen in init's filesystem context. Note that security_initramfs_populated() needs the scope as well since it does use current->fs to derive the initramfs superblock. do_populate_rootfs() ← async_schedule_domain() ← kworker (async workqueue) May also run synchronously from PID 1 in case async workqueue is considered full. Overriding in that case is fine as well. Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-17-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) --- init/initramfs.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'init') diff --git a/init/initramfs.c b/init/initramfs.c index 20a18fcda48e..4e27b97a8844 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -716,7 +717,7 @@ static void __init populate_initrd_image(char *err) } #endif /* CONFIG_BLK_DEV_RAM */ -static void __init do_populate_rootfs(void *unused, async_cookie_t cookie) +static void __init unpack_initramfs(async_cookie_t cookie) { /* Load the built in initramfs */ char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size); @@ -724,7 +725,7 @@ static void __init do_populate_rootfs(void *unused, async_cookie_t cookie) panic_show_mem("%s", err); /* Failed to decompress INTERNAL initramfs */ if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE)) - goto done; + return; if (IS_ENABLED(CONFIG_BLK_DEV_RAM)) printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n"); @@ -739,9 +740,14 @@ static void __init do_populate_rootfs(void *unused, async_cookie_t cookie) printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err); #endif } +} -done: - security_initramfs_populated(); +static void __init do_populate_rootfs(void *unused, async_cookie_t cookie) +{ + scoped_with_init_fs() { + unpack_initramfs(cookie); + security_initramfs_populated(); + } /* * If the initrd region is overlapped with crashkernel reserved region, -- cgit v1.2.3