linux-stable.git/fs/udf, branch linux-3.12.y

udf: Check output buffer length when converting name to CS0

2016-02-24T09:29:52+00:00

commit bb00c898ad1ce40c4bb422a8207ae562e9aea7ae upstream.

If a name contains at least some characters with Unicode values
exceeding single byte, the CS0 output should have 2 bytes per character.
And if other input characters have single byte Unicode values, then
the single input byte is converted to 2 output bytes, and the length
of output becomes larger than the length of input. And if the input
name is long enough, the output length may exceed the allocated buffer
length.

All this means that conversion from UTF8 or NLS to CS0 requires
checking of output length in order to stop when it exceeds the given
output buffer size.

[JK: Make code return -ENAMETOOLONG instead of silently truncating the
name]

Signed-off-by: Andrew Gabbasov 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Prevent buffer overrun with multi-byte characters

2016-02-24T09:29:52+00:00

commit ad402b265ecf6fa22d04043b41444cdfcdf4f52d upstream.

udf_CS0toUTF8 function stops the conversion when the output buffer
length reaches UDF_NAME_LEN-2, which is correct maximum name length,
but, when checking, it leaves the space for a single byte only,
while multi-bytes output characters can take more space, causing
buffer overflow.

Similar error exists in udf_CS0toNLS function, that restricts
the output length to UDF_NAME_LEN, while actual maximum allowed
length is UDF_NAME_LEN-2.

In these cases the output can override not only the current buffer
length field, causing corruption of the name buffer itself, but also
following allocation structures, causing kernel crash.

Adjust the output length checks in both functions to prevent buffer
overruns in case of multi-bytes UTF8 or NLS characters.

Signed-off-by: Andrew Gabbasov 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: limit the maximum number of indirect extents in a row

2016-02-24T09:29:51+00:00

commit b0918d9f476a8434b055e362b83fa4fd1d462c3f upstream.

udf_next_aext() just follows extent pointers while extents are marked as
indirect. This can loop forever for corrupted filesystem. Limit number
the of indirect extents we are willing to follow in a row.

[JK: Updated changelog, limit, style]

Signed-off-by: Vegard Nossum 
Cc: Jan Kara 
Cc: Quentin Casasnovas 
Cc: Andrew Morton 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Check length of extended attributes and allocation descriptors

2015-06-23T15:12:16+00:00

commit 23b133bdc452aa441fcb9b82cbf6dd05cfd342d0 upstream.

Check length of extended attributes and allocation descriptors when
loading inodes from disk. Otherwise corrupted filesystems could confuse
the code and make the kernel oops.

Reported-by: Carl Henrik Lunde 
Cc: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Remove repeated loads blocksize

2015-06-23T15:10:32+00:00

commit 79144954278d4bb5989f8b903adcac7a20ff2a5a upstream.

Store blocksize in a local variable in udf_fill_inode() since it is used
a lot of times.

Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Check component length before reading it

2015-02-16T15:10:56+00:00

commit e237ec37ec154564f8690c5bd1795339955eeef9 upstream.

Check that length specified in a component of a symlink fits in the
input buffer we are reading. Also properly ignore component length for
component types that do not use it. Otherwise we read memory after end
of buffer for corrupted udf image.

Reported-by: Carl Henrik Lunde 
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Check path length when reading symlink

2015-02-16T15:10:55+00:00

commit 0e5cc9a40ada6046e6bc3bdfcd0c0d7e4b706b14 upstream.

Symlink reading code does not check whether the resulting path fits into
the page provided by the generic code. This isn't as easy as just
checking the symlink size because of various encoding conversions we
perform on path. So we have to check whether there is still enough space
in the buffer on the fly.

CC: stable@vger.kernel.org
Reported-by: Carl Henrik Lunde 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Verify i_size when loading inode

2015-02-16T15:10:47+00:00

commit e159332b9af4b04d882dbcfe1bb0117f0a6d4b58 upstream.

Verify that inode size is sane when loading inode with data stored in
ICB. Otherwise we may get confused later when working with the inode and
inode size is too big.

CC: stable@vger.kernel.org
Reported-by: Carl Henrik Lunde 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Verify symlink size before loading it

2015-01-07T16:55:18+00:00

commit a1d47b262952a45aae62bd49cfaf33dd76c11a2c upstream.

UDF specification allows arbitrarily large symlinks. However we support
only symlinks at most one block large. Check the length of the symlink
so that we don't access memory beyond end of the symlink block.

Reported-by: Carl Henrik Lunde 
Signed-off-by: Jan Kara 
Signed-off-by: Jiri Slaby

udf: Avoid infinite loop when processing indirect ICBs

2014-10-13T14:09:18+00:00

commit c03aa9f6e1f938618e6db2e23afef0574efeeb65 upstream.

We did not implement any bound on number of indirect ICBs we follow when
loading inode. Thus corrupted medium could cause kernel to go into an
infinite loop, possibly causing a stack overflow.

Fix the possible stack overflow by removing recursion from
__udf_read_inode() and limit number of indirect ICBs we follow to avoid
infinite loops.

Signed-off-by: Jan Kara 
Cc: Chuck Ebbert 
Signed-off-by: Jiri Slaby