libsepol/cil: Check for too many permissions in classes and commons
Fixes bug found by Nicolas Iooss as described below in the way suggested by Steve Lawrence.
Nicolass reported:
When compiling a CIL policy with more than 32 items in a class (e.g. in
(class capability (chown ...)) with many items),
cil_classorder_to_policydb() overflows perm_value_to_cil[class_index]
array. As this array is allocated on the heap through
calloc(PERMS_PER_CLASS+1, sizeof(...)), this makes secilc crash with the
following message:
*** Error in `/usr/bin/secilc': double free or corruption (!prev): 0x000000000062be80 ***
======= Backtrace: =========
/usr/lib/libc.so.6(+0x70c4b)[0x7ffff76a7c4b]
/usr/lib/libc.so.6(+0x76fe6)[0x7ffff76adfe6]
/usr/lib/libc.so.6(+0x777de)[0x7ffff76ae7de]
/lib/libsepol.so.1(+0x14fbda)[0x7ffff7b24bda]
/lib/libsepol.so.1(+0x152db8)[0x7ffff7b27db8]
/lib/libsepol.so.1(cil_build_policydb+0x63)[0x7ffff7af8723]
/usr/bin/secilc[0x40273b]
/usr/lib/libc.so.6(__libc_start_main+0xf1)[0x7ffff7657291]
/usr/bin/secilc[0x402f7a]
This bug has been found by fuzzing secilc with american fuzzy lop.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
3 files changed