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author | Peter Zijlstra <peterz@infradead.org> | 2022-06-14 23:15:37 +0200 |
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committer | Borislav Petkov <bp@suse.de> | 2022-06-27 10:33:58 +0200 |
commit | 15e67227c49a57837108acfe1c80570e1bd9f962 (patch) | |
tree | 1fd03816aa33ce35c51505a235fdf1f9fb58962d /arch/x86/kernel/module.c | |
parent | 0b53c374b9eff2255a386f1f1cfb9a928e52a5ae (diff) | |
download | linux-15e67227c49a57837108acfe1c80570e1bd9f962.tar.gz linux-15e67227c49a57837108acfe1c80570e1bd9f962.tar.bz2 linux-15e67227c49a57837108acfe1c80570e1bd9f962.zip |
x86: Undo return-thunk damage
Introduce X86_FEATURE_RETHUNK for those afflicted with needing this.
[ bp: Do only INT3 padding - simpler. ]
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>
Diffstat (limited to 'arch/x86/kernel/module.c')
-rw-r--r-- | arch/x86/kernel/module.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index b98ffcf4d250..67828d973389 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -253,7 +253,7 @@ int module_finalize(const Elf_Ehdr *hdr, { const Elf_Shdr *s, *text = NULL, *alt = NULL, *locks = NULL, *para = NULL, *orc = NULL, *orc_ip = NULL, - *retpolines = NULL, *ibt_endbr = NULL; + *retpolines = NULL, *returns = NULL, *ibt_endbr = NULL; char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { @@ -271,6 +271,8 @@ int module_finalize(const Elf_Ehdr *hdr, orc_ip = s; if (!strcmp(".retpoline_sites", secstrings + s->sh_name)) retpolines = s; + if (!strcmp(".return_sites", secstrings + s->sh_name)) + returns = s; if (!strcmp(".ibt_endbr_seal", secstrings + s->sh_name)) ibt_endbr = s; } @@ -287,6 +289,10 @@ int module_finalize(const Elf_Ehdr *hdr, void *rseg = (void *)retpolines->sh_addr; apply_retpolines(rseg, rseg + retpolines->sh_size); } + if (returns) { + void *rseg = (void *)returns->sh_addr; + apply_returns(rseg, rseg + returns->sh_size); + } if (alt) { /* patch .altinstructions */ void *aseg = (void *)alt->sh_addr; |