From: Masami Hiramatsu <[email protected]> Fix to check the write(2) failure including partial write correctly and try to rollback the partial write, because if there is no BOOTCONFIG_MAGIC string, we can not remove it.
Link: https://lkml.kernel.org/r/160576521135.320071.3883101436675969998.stgit@devnote2 Fixes: 85c46b78da58 ("bootconfig: Add bootconfig magic word for indicating bootconfig explicitly") Suggested-by: Linus Torvalds <[email protected]> Signed-off-by: Masami Hiramatsu <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]> --- tools/bootconfig/main.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c index 52eb2bbe8966..a0733cbb3c49 100644 --- a/tools/bootconfig/main.c +++ b/tools/bootconfig/main.c @@ -337,6 +337,7 @@ static int delete_xbc(const char *path) static int apply_xbc(const char *path, const char *xbc_path) { + struct stat stat; u32 size, csum; char *buf, *data; int ret, fd; @@ -394,16 +395,26 @@ static int apply_xbc(const char *path, const char *xbc_path) return ret; } /* TODO: Ensure the @path is initramfs/initrd image */ + if (fstat(fd, &stat) < 0) { + pr_err("Failed to get the size of %s\n", path); + goto out; + } ret = write(fd, data, size + 8); - if (ret < 0) { + if (ret < size + 8) { + if (ret < 0) + ret = -errno; pr_err("Failed to apply a boot config: %d\n", ret); - goto out; + if (ret < 0) + goto out; + goto out_rollback; } /* Write a magic word of the bootconfig */ ret = write(fd, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN); - if (ret < 0) { + if (ret < BOOTCONFIG_MAGIC_LEN) { + if (ret < 0) + ret = -errno; pr_err("Failed to apply a boot config magic: %d\n", ret); - goto out; + goto out_rollback; } ret = 0; out: @@ -411,6 +422,17 @@ static int apply_xbc(const char *path, const char *xbc_path) free(data); return ret; + +out_rollback: + /* Map the partial write to -ENOSPC */ + if (ret >= 0) + ret = -ENOSPC; + if (ftruncate(fd, stat.st_size) < 0) { + ret = -errno; + pr_err("Failed to rollback the write error: %d\n", ret); + pr_err("The initrd %s may be corrupted. Recommend to rebuild.\n", path); + } + goto out; } static int usage(void) -- 2.28.0
