From cff75e0b6fe835800f8e08a32d731119cd9e3b79 Mon Sep 17 00:00:00 2001 From: Daniel Thompson Date: Mon, 8 May 2017 15:56:57 -0700 Subject: initramfs: provide a way to ignore image provided by bootloader Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel to override the command line provided by an inflexible bootloader. However there is currrently no way for the kernel to override the initramfs image provided by the bootloader meaning there are still ways for bootloaders to make things difficult for us. Fix this by introducing INITRAMFS_FORCE which can prevent the kernel from loading the bootloader supplied image. We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the system has an inflexible bootloader. This allow us to avoid presenting this config option to users of systems where inflexible bootloaders aren't usually a problem. Link: http://lkml.kernel.org/r/20170217121940.30126-1-daniel.thompson@linaro.org Signed-off-by: Daniel Thompson Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/initramfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init') diff --git a/init/initramfs.c b/init/initramfs.c index 8daf7ac6c7e2..9d180273ee8c 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -613,7 +613,7 @@ static int __init populate_rootfs(void) if (err) panic("%s", err); /* Failed to decompress INTERNAL initramfs */ /* If available load the bootloader supplied initrd */ - if (initrd_start) { + if (initrd_start && !IS_ENABLED(CONFIG_INITRAMFS_FORCE)) { #ifdef CONFIG_BLK_DEV_RAM int fd; printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n"); -- cgit v1.2.3 From 046aa1265f08d8400bd4b63171238c9daba15ec3 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 8 May 2017 15:57:00 -0700 Subject: initramfs: use vfs_stat/lstat directly sys_newlstat is a system call implementation that is meant for user space, and that copies kernel-internal data structure to the user format, which is not needed for in-kernel users. Further, as we rearrange the system call implementation so we can extend it with 64-bit time_t, the prototype for sys_newlstat changes. This changes the initramfs code to use vfs_lstat directly, to get it out of the way of the time_t changes, and make it slightly more efficient in the process. Along the same lines we also replace sys_stat and sys_stat64 with vfs_stat. Link: http://lkml.kernel.org/r/20170314214932.4052842-1-arnd@arndb.de Signed-off-by: Arnd Bergmann Cc: Alexander Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/do_mounts.h | 22 ++++------------------ init/initramfs.c | 12 ++++++------ 2 files changed, 10 insertions(+), 24 deletions(-) (limited to 'init') diff --git a/init/do_mounts.h b/init/do_mounts.h index 067af1d9e8b6..282d65bfd674 100644 --- a/init/do_mounts.h +++ b/init/do_mounts.h @@ -19,29 +19,15 @@ static inline int create_dev(char *name, dev_t dev) return sys_mknod(name, S_IFBLK|0600, new_encode_dev(dev)); } -#if BITS_PER_LONG == 32 static inline u32 bstat(char *name) { - struct stat64 stat; - if (sys_stat64(name, &stat) != 0) + struct kstat stat; + if (vfs_stat(name, &stat) != 0) return 0; - if (!S_ISBLK(stat.st_mode)) + if (!S_ISBLK(stat.mode)) return 0; - if (stat.st_rdev != (u32)stat.st_rdev) - return 0; - return stat.st_rdev; -} -#else -static inline u32 bstat(char *name) -{ - struct stat stat; - if (sys_newstat(name, &stat) != 0) - return 0; - if (!S_ISBLK(stat.st_mode)) - return 0; - return stat.st_rdev; + return stat.rdev; } -#endif #ifdef CONFIG_BLK_DEV_RAM diff --git a/init/initramfs.c b/init/initramfs.c index 9d180273ee8c..8a532050043f 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -312,10 +312,10 @@ static int __init maybe_link(void) static void __init clean_path(char *path, umode_t fmode) { - struct stat st; + struct kstat st; - if (!sys_newlstat(path, &st) && (st.st_mode ^ fmode) & S_IFMT) { - if (S_ISDIR(st.st_mode)) + if (!vfs_lstat(path, &st) && (st.mode ^ fmode) & S_IFMT) { + if (S_ISDIR(st.mode)) sys_rmdir(path); else sys_unlink(path); @@ -581,13 +581,13 @@ static void __init clean_rootfs(void) num = sys_getdents64(fd, dirp, BUF_SIZE); while (num > 0) { while (num > 0) { - struct stat st; + struct kstat st; int ret; - ret = sys_newlstat(dirp->d_name, &st); + ret = vfs_lstat(dirp->d_name, &st); WARN_ON_ONCE(ret); if (!ret) { - if (S_ISDIR(st.st_mode)) + if (S_ISDIR(st.mode)) sys_rmdir(dirp->d_name); else sys_unlink(dirp->d_name); -- cgit v1.2.3