Protect access to fore200e->available_cell_rate with rate_mtx lock to
prevent potential data race.
In this case, since the update depends on a prior read, a data race
could lead to a wrong fore200e.available_cell_rate value.
The field fore200e.available_cell_rate is generally protected by the lock
fore200e.rate_mtx when accessed. In all other read and write cases, this
field is consistently protected by the lock, except for this case and
during initialization.
This potential bug was detected by our experimental static analysis tool,
which analyzes locking APIs and paired functions to identify data races
and atomicity violations.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable(a)vger.kernel.org
Signed-off-by: Gui-Dong Han <2045gemini(a)gmail.com>
---
v2:
* Added a description of the data race hazard in fore200e_open(), as
suggested by Jakub Kicinski and Simon Horman.
---
drivers/atm/fore200e.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/atm/fore200e.c b/drivers/atm/fore200e.c
index 4fea1149e003..f62e38571440 100644
--- a/drivers/atm/fore200e.c
+++ b/drivers/atm/fore200e.c
@@ -1374,7 +1374,9 @@ fore200e_open(struct atm_vcc *vcc)
vcc->dev_data = NULL;
+ mutex_lock(&fore200e->rate_mtx);
fore200e->available_cell_rate += vcc->qos.txtp.max_pcr;
+ mutex_unlock(&fore200e->rate_mtx);
kfree(fore200e_vcc);
return -EINVAL;
--
2.25.1
For some odd reason 5.10 kernel series doesn't compile with a newer
toolchain since 2025-02-09:
2025-02-09T17:32:07.7991299Z GEN .version
2025-02-09T17:32:07.8270062Z CHK include/generated/compile.h
2025-02-09T17:32:07.8540777Z LD vmlinux.o
2025-02-09T17:32:11.7210899Z MODPOST vmlinux.symvers
2025-02-09T17:32:12.0869599Z MODINFO modules.builtin.modinfo
2025-02-09T17:32:12.1403022Z GEN modules.builtin
2025-02-09T17:32:12.1475659Z LD .tmp_vmlinux.btf
2025-02-09T17:32:19.6117204Z BTF .btf.vmlinux.bin.o
2025-02-09T17:32:31.2916650Z LD .tmp_vmlinux.kallsyms1
2025-02-09T17:32:34.8731104Z KSYMS .tmp_vmlinux.kallsyms1.S
2025-02-09T17:32:35.4910608Z AS .tmp_vmlinux.kallsyms1.o
2025-02-09T17:32:35.9662538Z LD .tmp_vmlinux.kallsyms2
2025-02-09T17:32:39.2595984Z KSYMS .tmp_vmlinux.kallsyms2.S
2025-02-09T17:32:39.8802028Z AS .tmp_vmlinux.kallsyms2.o
2025-02-09T17:32:40.3659440Z LD vmlinux
2025-02-09T17:32:48.0031558Z BTFIDS vmlinux
2025-02-09T17:32:48.0143553Z FAILED unresolved symbol filp_close
2025-02-09T17:32:48.5019928Z make: *** [Makefile:1207: vmlinux] Error 255
2025-02-09T17:32:48.5061241Z ==> ERROR: A failure occurred in build().
5.10.234 built fine couple of days ago with the older one. There were
slight changes made. 5.4 and 5.15 still compile.
Wonder what might be missing here ...
--
Best, Philip
Dear Kernel maintainers,
I think i'm encountering (for the first time in years !) a regression
with the "6.7.arch3-1" kernel (whereas no issues with
"6.6.10.arch1-1", on which i reverted).
I'm running a (up-to-date, and non-LTS) ARCHLINUX desktop, on a ASUS
B560-I motherboard, with 3 monitors (attached to a 4-HDMI outputs
card), plus an audio S/PDIF optic output at motherboard level.
With the latest kernel, the S/PIDF optic output of the motherboard is
NOT detected anymore (and i haven't been able to see / find anything
in the logs at quick glance, neither journalctl -xe nor dmesg).
Once reverted to 6.6.10, everything is fine again.
For example, in a working situation (6.6.10), i have :
cat /proc/asound/pcm
00-00: ALC1220 Analog : ALC1220 Analog : playback 1 : capture 1
00-01: ALC1220 Digital : ALC1220 Digital : playback 1
00-02: ALC1220 Alt Analog : ALC1220 Alt Analog : capture 1
01-03: HDMI 0 : HDMI 0 : playback 1
01-07: HDMI 1 : HDMI 1 : playback 1
01-08: HDMI 2 : HDMI 2 : playback 1
01-09: HDMI 3 : HDMI 3 : playback 1
Whereas while on the latest 6.7 kernel, i only had the 4 HDMI lines
(linked to a NVIDIA T600 card, with 4 HDMI outputs) and not the three
first ones (attached to the motherboard).
(of course i did several tests with 6.7, reboot, ... without any changes)
Any idea ?
Best regards
--
Serge.