diff options
| author | Pau Espin Pedrol <pespin@sysmocom.de> | 2021-06-30 16:03:06 +0200 |
|---|---|---|
| committer | Pau Espin Pedrol <pespin@sysmocom.de> | 2021-07-01 13:09:10 +0200 |
| commit | 4f67a9bf4610c9e948f0d81f3b039f36675180a3 (patch) | |
| tree | bf7f2aca513c0df2f2eaf2f4772a779e2558898b /src/pdch.h | |
| parent | 1989a190664ca1d4169c80336b2ecc00426c84f1 (diff) | |
pdch: Fix heap-use-after-free in pdch->ulc
In existing previous code, pdch->ulc would be freed in
gprs_rlcmac_pdch::free_resources() when it became disabled as per PCUIF
info_ind (for instance, when a DYN TS is switched PDCH->SDCCH8).
However, pdch->ulc was so far only allocated during pdch_init, which is
only called during bts_alloc() time.
Hence, after first info_ind disabling it, if it became again enabled
(again by info_ind re-enabling it after SDCCH8 was not longer in use),
the pdch->ulc would be used again but it would point to freed memory.
Let's rearrange how/when resources are freed to make it more logical.
With this patch, pdch internal resources are freed upon ->disable(), and
re-allocated upon ->enable().
Change-Id: Id51f5f6a54ac9f24b784c17bc360ac38f5726fc7
Diffstat (limited to 'src/pdch.h')
| -rw-r--r-- | src/pdch.h | 5 |
1 files changed, 3 insertions, 2 deletions
@@ -55,8 +55,6 @@ struct gprs_rlcmac_pdch { bool add_paging(uint8_t chan_needed, const struct osmo_mobile_identity *mi); - void free_resources(); - bool is_enabled() const; void enable(); @@ -145,6 +143,8 @@ private: enum gprs_rlcmac_tbf_direction dir); gprs_rlcmac_tbf *tbf_by_tfi(uint8_t tfi, enum gprs_rlcmac_tbf_direction dir); + + void free_resources(); #endif uint8_t m_num_tbfs[2]; @@ -191,6 +191,7 @@ extern "C" { void pdch_init(struct gprs_rlcmac_pdch *pdch, struct gprs_rlcmac_trx *trx, uint8_t ts_nr); void pdch_free_all_tbf(struct gprs_rlcmac_pdch *pdch); void pdch_disable(struct gprs_rlcmac_pdch *pdch); +bool pdch_is_enabled(const struct gprs_rlcmac_pdch *pdch); #ifdef __cplusplus } #endif |