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5 commits

Author SHA1 Message Date
Ksawlii
3177c82a6a Revert "tomoyo: fallback to realpath if symlink's pathname does not exist"
This reverts commit 8d86e29a54.
2024-11-24 00:23:01 +01:00
Tetsuo Handa
8d86e29a54 tomoyo: fallback to realpath if symlink's pathname does not exist
commit ada1986d07976d60bed5017aa38b7f7cf27883f7 upstream.

Alfred Agrell found that TOMOYO cannot handle execveat(AT_EMPTY_PATH)
inside chroot environment where /dev and /proc are not mounted, for
commit 51f39a1f0cea ("syscalls: implement execveat() system call") missed
that TOMOYO tries to canonicalize argv[0] when the filename fed to the
executed program as argv[0] is supplied using potentially nonexistent
pathname.

Since "/dev/fd/<fd>" already lost symlink information used for obtaining
that <fd>, it is too late to reconstruct symlink's pathname. Although
<filename> part of "/dev/fd/<fd>/<filename>" might not be canonicalized,
TOMOYO cannot use tomoyo_realpath_nofollow() when /dev or /proc is not
mounted. Therefore, fallback to tomoyo_realpath_from_path() when
tomoyo_realpath_nofollow() failed.

Reported-by: Alfred Agrell <blubban@gmail.com>
Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1082001
Fixes: 51f39a1f0cea ("syscalls: implement execveat() system call")
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:45 +01:00
Tetsuo Handa
be19f17d48 tomoyo: fix UAF write bug in tomoyo_write_control()
commit 2f03fc340cac9ea1dc63cbf8c93dd2eb0f227815 upstream.

Since tomoyo_write_control() updates head->write_buf when write()
of long lines is requested, we need to fetch head->write_buf after
head->io_sem is held.  Otherwise, concurrent write() requests can
cause use-after-free-write and double-free problems.

Reported-by: Sam Sun <samsun1006219@gmail.com>
Closes: https://lkml.kernel.org/r/CAEkJfYNDspuGxYx5kym8Lvp--D36CMDUErg4rxfWFJuPbbji8g@mail.gmail.com
Fixes: bd03a3e4c9a9 ("TOMOYO: Add policy namespace support.")
Cc:  <stable@vger.kernel.org> # Linux 3.1+
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 23:18:29 +01:00
Alfred Piccioni
1efed4682d lsm: new security_file_ioctl_compat() hook
commit f1bb47a31dff6d4b34fb14e99850860ee74bb003 upstream.

Some ioctl commands do not require ioctl permission, but are routed to
other permissions such as FILE_GETATTR or FILE_SETATTR. This routing is
done by comparing the ioctl cmd to a set of 64-bit flags (FS_IOC_*).

However, if a 32-bit process is running on a 64-bit kernel, it emits
32-bit flags (FS_IOC32_*) for certain ioctl operations. These flags are
being checked erroneously, which leads to these ioctl operations being
routed to the ioctl permission, rather than the correct file
permissions.

This was also noted in a RED-PEN finding from a while back -
"/* RED-PEN how should LSM module know it's handling 32bit? */".

This patch introduces a new hook, security_file_ioctl_compat(), that is
called from the compat ioctl syscall. All current LSMs have been changed
to support this hook.

Reviewing the three places where we are currently using
security_file_ioctl(), it appears that only SELinux needs a dedicated
compat change; TOMOYO and SMACK appear to be functional without any
change.

Cc: stable@vger.kernel.org
Fixes: 0b24dcb7f2f7 ("Revert "selinux: simplify ioctl checking"")
Signed-off-by: Alfred Piccioni <alpic@google.com>
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
[PM: subject tweak, line length fixes, and alignment corrections]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:12:58 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00