diff options
| author | Chang S. Bae <[email protected]> | 2020-05-28 16:13:47 -0400 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2020-06-18 15:46:59 +0200 |
| commit | fddf8ba1e48860211c9639d00883833b42fcc1e0 (patch) | |
| tree | b143d64ae6990fc1d93cc0412907c520fd4ee300 /lib/test_overflow.c | |
| parent | b3a9e3b9622ae10064826dccb4f7a52bd88c7407 (diff) | |
x86/ptrace: Prevent ptrace from clearing the FS/GS selector
When a ptracer writes a ptracee's FS/GSBASE with a different value, the
selector is also cleared. This behavior is not correct as the selector
should be preserved.
Update only the base value and leave the selector intact. To simplify the
code further remove the conditional checking for the same value as this
code is not performance critical.
The only recognizable downside of this change is when the selector is
already nonzero on write. The base will be reloaded according to the
selector. But the case is highly unexpected in real usages.
[ tglx: Massage changelog ]
Suggested-by: Andy Lutomirski <[email protected]>
Signed-off-by: Chang S. Bae <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Diffstat (limited to 'lib/test_overflow.c')
0 files changed, 0 insertions, 0 deletions