From: Masami Hiramatsu <mhiramat@xxxxxxxxxx> [ Upstream commit a995e6bc0524450adfd6181dfdcd9d0520cfaba5 ] 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 <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 e0878f5f74b1b..ffd6a358925da 100644 --- a/tools/bootconfig/main.c +++ b/tools/bootconfig/main.c @@ -274,6 +274,7 @@ static void show_xbc_error(const char *data, const char *msg, int pos) int apply_xbc(const char *path, const char *xbc_path) { + struct stat stat; u32 size, csum; char *buf, *data; int ret, fd; @@ -330,16 +331,26 @@ int apply_xbc(const char *path, const char *xbc_path) return fd; } /* 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: @@ -347,6 +358,17 @@ out: 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; } int usage(void) -- 2.27.0
