diff options
author | Pau Espin Pedrol <pespin@sysmocom.de> | 2018-08-22 21:54:12 +0200 |
---|---|---|
committer | Pau Espin Pedrol <pespin@sysmocom.de> | 2018-08-23 16:47:30 +0200 |
commit | 9862bcb5cdb9ece0acfdfb7c81e00c05fcd33ad3 (patch) | |
tree | 8714417cf3bf91e37afca0de305de92f795a1e23 /include/osmocom | |
parent | 5f0a63d67833538e78aaa57c4965bf2ecce89035 (diff) |
Fix heap-use-after-free due to OML link destruction
ipaccess_drop_oml was being called inside an osmo_fd cb context, were
-EBADF must be returned if the structure holding the osmo_fd is freed.
In the middle of the path (see OS#3495 for path tree) it goes through a
signal dispatch, so it's impossible to make sure we return some value to
the osmo_fd cb. As a result, it is required to defer dropping the OML
Link from current code path and do it through a timer.
Fixes following ASan report:
20180822124927913 <0004> abis_nm.c:787 OC=RADIO-CARRIER(02) INST=(00,00,ff): CHANGE ADMINISTRATIVE STATE NACK CAUSE=Message cannot be performed
20180822124927913 <0004> osmo_bsc_main.c:186 Got CHANGE ADMINISTRATIVE STATE NACK going to drop the OML links.
20180822124927913 <0015> bts_ipaccess_nanobts.c:406 (bts=0) Dropping OML link.
...
=================================================================
==17607==ERROR: AddressSanitizer: heap-use-after-free on address 0x62e000060a68 at pc 0x7f5ea8e27086 bp 0x7ffde92b6d80 sp 0x7ffde92b6d78
READ of size 8 at 0x62e000060a68 thread T0
#0 0x7f5ea8e27085 in handle_ts1_write input/ipaccess.c:371
#1 0x7f5ea8e27085 in ipaccess_fd_cb input/ipaccess.c:391
#2 0x7f5ea9147ca8 in osmo_fd_disp_fds libosmocore/src/select.c:217
#3 0x7f5ea9147ca8 in osmo_select_main libosmocore/src/select.c:257
#4 0x555813ab79d6 in main osmo-bsc/osmo_bsc_main.c:922
#5 0x7f5ea76d02e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
#6 0x555813ab84e9 in _start (/bin/osmo-bsc+0x34d4e9)
Fixes: OS#3495
Change-Id: I7c794c763481c28e8c35dc9b11d27969e16feb3c
Diffstat (limited to 'include/osmocom')
-rw-r--r-- | include/osmocom/bsc/gsm_data.h | 2 | ||||
-rw-r--r-- | include/osmocom/bsc/ipaccess.h | 1 |
2 files changed, 3 insertions, 0 deletions
diff --git a/include/osmocom/bsc/gsm_data.h b/include/osmocom/bsc/gsm_data.h index f85887ac7..b827d0a5a 100644 --- a/include/osmocom/bsc/gsm_data.h +++ b/include/osmocom/bsc/gsm_data.h @@ -923,6 +923,8 @@ struct gsm_bts { struct gsm_e1_subslot oml_e1_link; uint8_t oml_tei; struct e1inp_sign_link *oml_link; + /* Timer to use for deferred drop of OML link, see \ref ipaccess_drop_oml_deferred */ + struct osmo_timer_list oml_drop_link_timer; /* when OML link was established */ time_t uptime; diff --git a/include/osmocom/bsc/ipaccess.h b/include/osmocom/bsc/ipaccess.h index 3d0f6128c..692e79576 100644 --- a/include/osmocom/bsc/ipaccess.h +++ b/include/osmocom/bsc/ipaccess.h @@ -31,6 +31,7 @@ struct ipac_ext_lac_cmd { } __attribute__((packed)); void ipaccess_drop_oml(struct gsm_bts *bts); +void ipaccess_drop_oml_deferred(struct gsm_bts *bts); void ipaccess_drop_rsl(struct gsm_bts_trx *trx); struct sdp_header_item { |