Re: R: Linux kernel source archive vulnerable

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sep 13, 2006, at 01:34:01, David Wagner wrote:
Willy Tarreau  wrote:
The initial reason is that Linus now uses the "git-tar-tree" command
which creates the full tar archive from the tree. It does not use tar,
it know how to produce the tar format itself. The command has to set
permissions on the files, and by default, it sets full permissions to
the files.

Ahh, thanks for the explanation.  That's helpful.

So it sounds like git-tar-tree has a bug; its default isn't setting
meaningful permissions on the files that it puts into the tar archive.
I hope the maintainers of git-tar-tree will consider fixing this bug.

Let me reiterate:  This is not a bug!

Here are a few facts:

1) When I run "touch foo", the "touch" command uses permissions 0666, which are modified by my umask before hitting the FS. (same behavior for all UIDs)

2) When I run "gcc -c foo.c -o foo.o", the "gcc" command uses permissions 0666, which are modified by my umask before hitting the FS. (same behavior for all UIDs)

3) When I run "vim foo.c", the "vim" command uses permissions 0666 for new files, which are modified by my umask before hitting the FS. (same behavior for all UIDs)

4) When I run "tar -xvf foo.tar" as a normal user, the "tar" command uses permissions from the archive for new files, which are modified by my umask before hitting the FS.

5)  Do you see the pattern here?


Now when I run that tar command as root, for some reason they assume that just because my UID is 0 I want to try to ignore my umask while extracting my j_random.tar file. How does this follow from the behavior of any other programs mentioned above?

The program "git-tar-tree" has no bug. It creates the tar archive such that when extracted as a normal user the users' umask is applied exactly as for every other standard program. If anything the "bug" is in tar assuming that every archive file extracted as UID 0 is a backup, or in the admin assuming that tar doesn't behave differently when run as UID 0.

Cheers,
Kyle Moffett

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux