In the Linux kernel, the following vulnerability has been resolved: tty: n_gsm: fix possible out-of-bounds in gsm0_receive() Assuming the following: - side A configures the n_gsm in basic option mode - side B sends the header of a basic option mode frame with data length 1 - side A switches to advanced option mode - side B sends 2 data bytes which exceeds gsm->len Reason: gsm->len is not used in advanced option mode. - side A switches to basic option mode - side B keeps sending until gsm0_receive() writes past gsm->buf Reason: Neither gsm->state nor gsm->len have been reset after reconfiguration. Fix this by changing gsm->count to gsm->len comparison from equal to less than. Also add upper limit checks against the constant MAX_MRU in gsm0_receive() and gsm1_receive() to harden against memory corruption of gsm->len and gsm->mru. All other checks remain as we still need to limit the data according to the user configuration and actual payload size.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | <= 6.1.76-1 | linux_6.1.76-1_all.deb |
Debian | 11 | all | linux | <= 5.10.209-2 | linux_5.10.209-2_all.deb |
Debian | 10 | all | linux | < 4.19.316-1 | linux_4.19.316-1_all.deb |
Debian | 999 | all | linux | < 6.8.12-1 | linux_6.8.12-1_all.deb |
Debian | 13 | all | linux | < 6.8.12-1 | linux_6.8.12-1_all.deb |