2020-11-17 09:55:40

by Masami Hiramatsu

[permalink] [raw]
Subject: [PATCH v3 1/3] tools/bootconfig: Fix to check the write failure correctly

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.

Fixes: 85c46b78da58 ("bootconfig: Add bootconfig magic word for indicating bootconfig explicitly")
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
---
tools/bootconfig/main.c | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c
index eb92027817a7..f7b89a50404c 100644
--- a/tools/bootconfig/main.c
+++ b/tools/bootconfig/main.c
@@ -332,6 +332,7 @@ 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;
@@ -388,16 +389,26 @@ static 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:
@@ -405,6 +416,14 @@ static int apply_xbc(const char *path, const char *xbc_path)
free(data);

return ret;
+
+out_rollback:
+ 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)


2020-11-17 12:13:50

by Yu Chen

[permalink] [raw]
Subject: Re: [PATCH v3 1/3] tools/bootconfig: Fix to check the write failure correctly

On Tue, Nov 17, 2020 at 5:53 PM Masami Hiramatsu <[email protected]> wrote:
>
> 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.
>
> Fixes: 85c46b78da58 ("bootconfig: Add bootconfig magic word for indicating bootconfig explicitly")
> Suggested-by: Linus Torvalds <[email protected]>
> Signed-off-by: Masami Hiramatsu <[email protected]>
For [1/3] and [2/3]
Tested-by: Chen Yu <[email protected]>

--
Thanks,
Chenyu

2020-11-18 13:41:39

by Masami Hiramatsu

[permalink] [raw]
Subject: Re: [PATCH v3 1/3] tools/bootconfig: Fix to check the write failure correctly

On Tue, 17 Nov 2020 20:10:10 +0800
Chen Yu <[email protected]> wrote:

> On Tue, Nov 17, 2020 at 5:53 PM Masami Hiramatsu <[email protected]> wrote:
> >
> > 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.
> >
> > Fixes: 85c46b78da58 ("bootconfig: Add bootconfig magic word for indicating bootconfig explicitly")
> > Suggested-by: Linus Torvalds <[email protected]>
> > Signed-off-by: Masami Hiramatsu <[email protected]>
> For [1/3] and [2/3]
> Tested-by: Chen Yu <[email protected]>

Thank you Chen,

BTW, I found another bug in bootconfig error handling.
Steve, did you already pick this series? If not yet, I will update the seires to add that fix.

Thank you,

>
> --
> Thanks,
> Chenyu


--
Masami Hiramatsu <[email protected]>

2020-11-18 14:07:54

by Steven Rostedt

[permalink] [raw]
Subject: Re: [PATCH v3 1/3] tools/bootconfig: Fix to check the write failure correctly

On Wed, 18 Nov 2020 22:37:08 +0900
Masami Hiramatsu <[email protected]> wrote:

> BTW, I found another bug in bootconfig error handling.
> Steve, did you already pick this series? If not yet, I will update the seires to add that fix.

No, I was about to pull it in today. I'll wait for your new series.

Thanks!

-- Steve