commit cd648b8a8fd5071d232242d5ee7ee3c0815776af upstream.
If filesystem groups are artifically small (using parameter -g to
mkfs.ext4), ext4_mb_normalize_request() can result in a request that is
larger than a block group. Trim the request size to not confuse
allocation code.
Reported-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 03e916fa8b5577d85471452a3d0c5738aa658dae upstream.
Inside ext4_ext_shift_extents() function ext4_find_extent() is called
without EXT4_EX_NOCACHE flag, which should prevent cache population.
This leads to oudated offsets in the extents tree and wrong blocks
afterwards.
Patch fixes the problem providing EXT4_EX_NOCACHE flag for each
ext4_find_extents() call inside ext4_ext_shift_extents function.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a9b8cba62c0741109c33a2be700ff3d7703a7c2 upstream.
While doing 'insert range' start block should be also shifted right.
The bug can be easily reproduced by the following test:
ptr = malloc(4096);
assert(ptr);
fd = open("./ext4.file", O_CREAT | O_TRUNC | O_RDWR, 0600);
assert(fd >= 0);
rc = fallocate(fd, 0, 0, 8192);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = 0xbeef;
rc = pwrite(fd, ptr, 4096, 0);
assert(rc == 4096);
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
for (block = 2; block < 1000; block++) {
rc = fallocate(fd, FALLOC_FL_INSERT_RANGE, 4096, 4096);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = block;
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
}
Because start block is not included in the range the hole appears at
the wrong offset (just after the desired offset) and the following
pwrite() overwrites already existent block, keeping hole untouched.
Simple way to verify wrong behaviour is to check zeroed blocks after
the test:
$ hexdump ./ext4.file | grep '0000 0000'
The root cause of the bug is a wrong range (start, stop], where start
should be inclusive, i.e. [start, stop].
This patch fixes the problem by including start into the range. But
not to break left shift (range collapse) stop points to the beginning
of the a block, not to the end.
The other not obvious change is an iterator check on validness in a
main loop. Because iterator is unsigned the following corner case
should be considered with care: insert a block at 0 offset, when stop
variables overflows and never becomes less than start, which is 0.
To handle this special case iterator is set to NULL to indicate that
end of the loop is reached.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
