kernel.git/fs/udf/super.c, branch linux-4.6.y

udf: Prevent stack overflow on corrupted filesystem mount

2016-08-16T07:33:18Z

commit a47241cdeee2689ee7089ec95cadfcf66588fbdb upstream. Presently, a corrupted or malicious UDF filesystem containing a very large number (or cycle) of Logical Volume Integrity Descriptor extent indirections may trigger a stack overflow and kernel panic in udf_load_logicalvolint() on mount. Replace the unnecessary recursion in udf_load_logicalvolint() with simple iteration. Set an arbitrary limit of 1000 indirections (which would have almost certainly overflowed the stack without this fix), and treat such cases as if there were no LVID. Signed-off-by: Alden Tondettar Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

udf: Fix conversion of 'dstring' fields to UTF8

2016-04-25T13:18:50Z

Commit 9293fcfbc1812a22ad5ce1b542eb90c1bbe01be1 ("udf: Remove struct ustr as non-needed intermediate storage"), while getting rid of 'struct ustr', does not take any special care of 'dstring' fields and effectively use fixed field length instead of actual string length, encoded in the last byte of the field. Also, commit 484a10f49387e4386bf2708532e75bf78ffea2cb ("udf: Merge linux specific translation into CS0 conversion function") introduced checking of the length of the string being converted, requiring proper alignment to number of bytes constituing each character. The UDF volume identifier is represented as a 32-bytes 'dstring', and needs to be converted from CS0 to UTF8, while mounting UDF filesystem. The changes in mentioned commits can in some cases lead to incorrect handling of volume identifier: - if the actual string in 'dstring' is of maximal length and does not have zero bytes separating it from dstring encoded length in last byte, that last byte may be included in conversion, thus making incorrect resulting string; - if the identifier is encoded with 2-bytes characters (compression code is 16), the length of 31 bytes (32 bytes of field length minus 1 byte of compression code), taken as the string length, is reported as an incorrect (unaligned) length, and the conversion fails, which in its turn leads to volume mounting failure. This patch introduces handling of 'dstring' encoded length field in udf_CS0toUTF8 function, that is used in all and only cases when 'dstring' fields are converted. Currently these cases are processing of Volume Identifier and Volume Set Identifier fields. The function is also renamed to udf_dstrCS0toUTF8 to distinctly indicate that it handles 'dstring' input. Signed-off-by: Andrew Gabbasov Signed-off-by: Jan Kara

udf: Remove struct ustr as non-needed intermediate storage

2016-02-09T12:05:23Z

Although 'struct ustr' tries to structurize the data by combining the string and its length, it doesn't actually make much benefit, since it saves only one parameter, but introduces an extra copying of the whole buffer, serving as an intermediate storage. It looks quite inefficient and not actually needed. This commit gets rid of the struct ustr by changing the parameters of some functions appropriately. Also, it removes using 'dstring' type, since it doesn't make much sense too. Just using the occasion, add a 'const' qualifier to udf_get_filename to make consistent parameters sets. Signed-off-by: Andrew Gabbasov Signed-off-by: Jan Kara

udf: Adjust UDF_NAME_LEN to better reflect actual restrictions

2016-02-09T12:05:23Z

Actual name length restriction is 254 bytes, this is used in 'ustr' structure, and this is what fits into UDF File Ident structures. And in most cases the constant is used as UDF_NAME_LEN-2. So, it's better to just modify the constant to make it closer to reality. Also, in some cases it's useful to have a separate constant for the maximum length of file name field in CS0 encoding in UDF File Ident structures. Also, remove the unused UDF_PATH_LEN constant. Signed-off-by: Andrew Gabbasov Signed-off-by: Jan Kara

tree wide: use kvfree() than conditional kfree()/vfree()

2016-01-23T01:02:18Z

There are many locations that do if (memory_was_allocated_by_vmalloc) vfree(ptr); else kfree(ptr); but kvfree() can handle both kmalloc()ed memory and vmalloc()ed memory using is_vmalloc_addr(). Unless callers have special reasons, we can replace this branch with kvfree(). Please check and reply if you found problems. Signed-off-by: Tetsuo Handa Acked-by: Michal Hocko Acked-by: Jan Kara Acked-by: Russell King Reviewed-by: Andreas Dilger Acked-by: "Rafael J. Wysocki" Acked-by: David Rientjes Cc: "Luck, Tony" Cc: Oleg Drokin Cc: Boris Petkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2016-01-15T19:51:51Z

Pull UDF fixes and quota cleanups from Jan Kara: "Several UDF fixes and some minor quota cleanups" * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: udf: Check output buffer length when converting name to CS0 udf: Prevent buffer overrun with multi-byte characters quota: constify qtree_fmt_operations structures udf: avoid uninitialized variable use udf: Fix lost indirect extent block udf: Factor out code for creating indirect extent udf: limit the maximum number of indirect extents in a row udf: limit the maximum number of TD redirections fs: make quota/dquot.c explicitly non-modular fs: make quota/netlink.c explicitly non-modular

kmemcg: account certain kmem allocations to memcg

2016-01-15T00:00:49Z

Mark those kmem allocations that are known to be easily triggered from userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to memcg. For the list, see below: - threadinfo - task_struct - task_delay_info - pid - cred - mm_struct - vm_area_struct and vm_region (nommu) - anon_vma and anon_vma_chain - signal_struct - sighand_struct - fs_struct - files_struct - fdtable and fdtable->full_fds_bits - dentry and external_name - inode for all filesystems. This is the most tedious part, because most filesystems overwrite the alloc_inode method. The list is far from complete, so feel free to add more objects. Nevertheless, it should be close to "account everything" approach and keep most workloads within bounds. Malevolent users will be able to breach the limit, but this was possible even with the former "account everything" approach (simply because it did not account everything in fact). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Vladimir Davydov Acked-by: Johannes Weiner Acked-by: Michal Hocko Cc: Tejun Heo Cc: Greg Thelen Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

udf: limit the maximum number of TD redirections

2015-12-14T19:13:36Z

Filesystem fuzzing revealed that we could get stuck in the udf_process_sequence() loop. The maximum limit was chosen arbitrarily but fixes the problem I saw. Signed-off-by: Vegard Nossum Signed-off-by: Jan Kara

udf: Don't modify filesystem for read-only mounts

2015-08-20T12:58:35Z

When read-write mount of a filesystem is requested but we find out we can mount the filesystem only in read-only mode, we still modify LVID in udf_close_lvid(). That is both unnecessary and contrary to expectation that when we fall back to read-only mount we don't modify the filesystem. Make sure we call udf_close_lvid() only if we called udf_open_lvid() so that filesystem gets modified only if we verified we are allowed to write to it. Reported-by: Karel Zak Signed-off-by: Jan Kara

udf: fix udf_load_pvoldesc()

2015-05-21T13:19:15Z

There are some missing braces here which means this function never succeeds. Fixes: e9d4cf411f75 ('udf: improve error management in udf_CS0toUTF8()') Signed-off-by: Dan Carpenter Signed-off-by: Jan Kara