Description
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: don't drop the runtime PM reference twice in amdgpu_gpr amdgpu_debugfs_gpr_read() drops its runtime PM reference right after reading the wave registers. When copying them to userspace fails, it jumps to the err label, which drops the reference a second time. A read into a bad buffer on Navi31 either steals a reference somebody else holds (power/runtime_usage goes from 1 to 0) or underflows the count: amdgpu 0000:03:00.0: Runtime PM usage count underflow! The registers are already in the kernel buffer at that point, so finish the hardware access first and copy the buffer with a single copy_to_user() instead of the put_user() loop with its own error path. (cherry picked from commit 31035bbd74f7c3e10c163db875b8e67f8b50ee6a)
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
9eee152aab56d374edb9ad21b3db05f5cdda2fe6 to < 652b1f26125fe48aed5f4944698a85b457eef491affected9eee152aab56d374edb9ad21b3db05f5cdda2fe6 to < 253555a9baccefffe1f6e5f2fe54363c7c01ebb9affected9eee152aab56d374edb9ad21b3db05f5cdda2fe6 to < de9f6bcdb44f0e410031002e2f103826ea6b6259affected865e2dbadf6856c9219626fbd6154cac44e5fbcaaffected5.8.2 to < 5.9affected
Linux Linux
Default version status: affected
5.9affected0 to < 5.9unaffected6.18.59 to ≤ 6.18.*unaffected7.2.13 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected