| From de9a6284df8add6ec03e1d9981d0b6d0595bbc69 Mon Sep 17 00:00:00 2001 |
| From: Andrea Adami <andrea.adami@gmail.com> |
| Date: Mon, 10 Nov 2014 23:37:23 +0100 |
| Subject: [PATCH 4/4] kexecboot.c: workaround for absolute kernel and initrd |
| symlinks |
| |
| Add MOUNTPOINT prefix if the kernel/initrd symlinks start with '/'. |
| Do nothing if the path is a relative symbolic link or not a symlink. |
| |
| Fix following situation: |
| |
| root@mizar:/var/tmp# ls -al boot/ |
| total 2076 |
| drwxr-xr-x 2 root root 4096 lug 5 01:38 . |
| drwxrwxrwt 4 root root 4096 lug 5 12:26 .. |
| -rw-r--r-- 1 root root 831 lug 5 01:24 boot.cfg |
| -rw-r--r-- 1 root root 1322 lug 5 01:24 icon.xpm |
| lrwxrwxrwx 1 root root 34 lug 5 12:26 zImage -> |
| /boot/zImage-3.14.5-yocto-standard |
| -rw-r--r-- 1 root root 2106832 lug 5 01:20 zImage-3.14.5-yocto-standard |
| |
| Cannot open `/mnt/boot/zImage': No such file or directory |
| Nothing has been loaded! |
| |
| Signed-off-by: Andrea Adami <andrea.adami@gmail.com> |
| --- |
| kexecboot.c | 53 ++++++++++++++++++++++++++++++++++++++++++++--------- |
| 1 file changed, 44 insertions(+), 9 deletions(-) |
| |
| diff --git a/kexecboot.c b/kexecboot.c |
| index 7268d6b..8a7a7d2 100644 |
| --- a/kexecboot.c |
| +++ b/kexecboot.c |
| @@ -208,11 +208,16 @@ void start_kernel(struct params_t *params, int choice) |
| const char *load_argv[] = { NULL, "-l", NULL, NULL, NULL, NULL }; |
| const char *exec_argv[] = { NULL, "-e", NULL, NULL}; |
| |
| - char *cmdline_arg = NULL, *initrd_arg = NULL; |
| + char *cmdline_arg = NULL, *initrd_arg = NULL, *kernel_arg = NULL; |
| int n, idx, u; |
| struct stat sinfo; |
| struct boot_item_t *item; |
| |
| + /* buffer for readlink (could be truncated) */ |
| + char buf[512]; |
| + int len; |
| + |
| + |
| item = params->bootcfg->list[choice]; |
| |
| exec_argv[0] = kexec_path; |
| @@ -306,10 +311,17 @@ void start_kernel(struct params_t *params, int choice) |
| } |
| } |
| |
| + /* Mount boot device */ |
| + if ( -1 == mount(mount_dev, mount_point, mount_fstype, |
| + MS_RDONLY, NULL) ) { |
| + perror("Can't mount boot device"); |
| + exit(-1); |
| + } |
| + |
| /* fill '--initrd' option */ |
| if (item->initrd) { |
| /* allocate space */ |
| - n = sizeof(str_initrd_start) + strlen(item->initrd); |
| + n = sizeof(str_initrd_start) + strlen(item->initrd) + 1 + sizeof(mount_point) + sizeof(buf); |
| |
| initrd_arg = (char *)malloc(n); |
| if (NULL == initrd_arg) { |
| @@ -317,24 +329,46 @@ void start_kernel(struct params_t *params, int choice) |
| } else { |
| strcpy(initrd_arg, str_initrd_start); /* --initrd= */ |
| strcat(initrd_arg, item->initrd); |
| + |
| + if ((len = readlink(item->initrd, buf, sizeof(buf)-1)) != -1) { |
| + buf[len] = '\0'; |
| + /* Fix absolute symlinks: prepend MOUNTPOINT */ |
| + if (buf[0] == '/') { |
| + strcpy(initrd_arg, str_initrd_start); /* --initrd= */ |
| + strcat(initrd_arg, mount_point); |
| + strcat(initrd_arg, buf); |
| + } |
| + } |
| load_argv[idx] = initrd_arg; |
| ++idx; |
| } |
| } |
| |
| /* Append kernelpath as last arg of kexec */ |
| - load_argv[idx] = item->kernelpath; |
| + /* allocate space */ |
| + n = strlen(item->kernelpath) + 1 + sizeof(mount_point) + sizeof(buf); |
| + |
| + kernel_arg = (char *)malloc(n); |
| + if (NULL == kernel_arg) { |
| + perror("Can't allocate memory for kernel_arg"); |
| + } else { |
| + strcpy(kernel_arg, item->kernelpath); |
| + |
| + if ((len = readlink(item->kernelpath, buf, sizeof(buf)-1)) != -1) { |
| + buf[len] = '\0'; |
| + /* Fix absolute symlinks: prepend MOUNTPOINT */ |
| + if (buf[0] == '/') { |
| + strcpy(kernel_arg, mount_point); |
| + strcat(kernel_arg, buf); |
| + } |
| + } |
| + load_argv[idx] = kernel_arg; |
| + } |
| |
| DPRINTF("load_argv: %s, %s, %s, %s, %s", load_argv[0], |
| load_argv[1], load_argv[2], |
| load_argv[3], load_argv[4]); |
| |
| - /* Mount boot device */ |
| - if ( -1 == mount(mount_dev, mount_point, mount_fstype, |
| - MS_RDONLY, NULL) ) { |
| - perror("Can't mount boot device"); |
| - exit(-1); |
| - } |
| |
| /* Load kernel */ |
| n = fexecw(kexec_path, (char *const *)load_argv, envp); |
| @@ -347,6 +381,7 @@ void start_kernel(struct params_t *params, int choice) |
| |
| dispose(cmdline_arg); |
| dispose(initrd_arg); |
| + dispose(kernel_arg); |
| |
| /* Check /proc/sys/net presence */ |
| if ( -1 == stat("/proc/sys/net", &sinfo) ) { |
| -- |
| 1.9.1 |
| |