diff options
Diffstat (limited to 'debian/patches/bugfix/x86/retbleed/0015-x86-entry-Avoid-very-early-RET.patch')
| -rw-r--r-- | debian/patches/bugfix/x86/retbleed/0015-x86-entry-Avoid-very-early-RET.patch | 59 |
1 files changed, 0 insertions, 59 deletions
diff --git a/debian/patches/bugfix/x86/retbleed/0015-x86-entry-Avoid-very-early-RET.patch b/debian/patches/bugfix/x86/retbleed/0015-x86-entry-Avoid-very-early-RET.patch deleted file mode 100644 index 71935dd77..000000000 --- a/debian/patches/bugfix/x86/retbleed/0015-x86-entry-Avoid-very-early-RET.patch +++ /dev/null @@ -1,59 +0,0 @@ -From: Peter Zijlstra <peterz@infradead.org> -Date: Tue, 14 Jun 2022 23:15:46 +0200 -Subject: x86/entry: Avoid very early RET -Origin: https://git.kernel.org/linus/7c81c0c9210c9bfab2bae76aab2999de5bad27db - -Commit - - ee774dac0da1 ("x86/entry: Move PUSH_AND_CLEAR_REGS out of error_entry()") - -manages to introduce a CALL/RET pair that is before SWITCH_TO_KERNEL_CR3, -which means it is before RETBleed can be mitigated. - -Revert to an earlier version of the commit in Fixes. Down side is that -this will bloat .text size somewhat. The alternative is fully reverting -it. - -The purpose of this patch was to allow migrating error_entry() to C, -including the whole of kPTI. Much care needs to be taken moving that -forward to not re-introduce this problem of early RETs. - -Fixes: ee774dac0da1 ("x86/entry: Move PUSH_AND_CLEAR_REGS out of error_entry()") -Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> -Signed-off-by: Borislav Petkov <bp@suse.de> -Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> -Signed-off-by: Borislav Petkov <bp@suse.de> ---- - arch/x86/entry/entry_64.S | 12 ++---------- - 1 file changed, 2 insertions(+), 10 deletions(-) - -diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S -index 4300ba49b5ee..9f5d6a4f293e 100644 ---- a/arch/x86/entry/entry_64.S -+++ b/arch/x86/entry/entry_64.S -@@ -322,14 +322,6 @@ SYM_CODE_END(ret_from_fork) - #endif - .endm - --/* Save all registers in pt_regs */ --SYM_CODE_START_LOCAL(push_and_clear_regs) -- UNWIND_HINT_FUNC -- PUSH_AND_CLEAR_REGS save_ret=1 -- ENCODE_FRAME_POINTER 8 -- RET --SYM_CODE_END(push_and_clear_regs) -- - /** - * idtentry_body - Macro to emit code calling the C function - * @cfunc: C function to be called -@@ -337,8 +329,8 @@ SYM_CODE_END(push_and_clear_regs) - */ - .macro idtentry_body cfunc has_error_code:req - -- call push_and_clear_regs -- UNWIND_HINT_REGS -+ PUSH_AND_CLEAR_REGS -+ ENCODE_FRAME_POINTER - - /* - * Call error_entry() and switch to the task stack if from userspace. |