From 3ed7b4d67c6745300c9b5c6baa55da1161b57f60 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Sep 2017 14:42:04 -0500 Subject: [PATCH] crypto: x86/des3_ede - Fix RBP usage Using RBP as a temporary register breaks frame pointer convention and breaks stack traces when unwinding from an interrupt in the crypto code. Use RSI instead of RBP for RT1. Since RSI is also used as a the 'dst' function argument, it needs to be saved on the stack until the argument is needed. Reported-by: Eric Biggers Reported-by: Peter Zijlstra Tested-by: Eric Biggers Acked-by: Eric Biggers Signed-off-by: Josh Poimboeuf Signed-off-by: Herbert Xu --- arch/x86/crypto/des3_ede-asm_64.S | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/arch/x86/crypto/des3_ede-asm_64.S b/arch/x86/crypto/des3_ede-asm_64.S index f3e91647ca27..8e49ce117494 100644 --- a/arch/x86/crypto/des3_ede-asm_64.S +++ b/arch/x86/crypto/des3_ede-asm_64.S @@ -64,12 +64,12 @@ #define RW2bh %ch #define RT0 %r15 -#define RT1 %rbp +#define RT1 %rsi #define RT2 %r14 #define RT3 %rdx #define RT0d %r15d -#define RT1d %ebp +#define RT1d %esi #define RT2d %r14d #define RT3d %edx @@ -177,13 +177,14 @@ ENTRY(des3_ede_x86_64_crypt_blk) * %rsi: dst * %rdx: src */ - pushq %rbp; pushq %rbx; pushq %r12; pushq %r13; pushq %r14; pushq %r15; + pushq %rsi; /* dst */ + read_block(%rdx, RL0, RR0); initial_permutation(RL0, RR0); @@ -241,6 +242,8 @@ ENTRY(des3_ede_x86_64_crypt_blk) round1(32+15, RL0, RR0, dummy2); final_permutation(RR0, RL0); + + popq %rsi /* dst */ write_block(%rsi, RR0, RL0); popq %r15; @@ -248,7 +251,6 @@ ENTRY(des3_ede_x86_64_crypt_blk) popq %r13; popq %r12; popq %rbx; - popq %rbp; ret; ENDPROC(des3_ede_x86_64_crypt_blk) @@ -432,13 +434,14 @@ ENTRY(des3_ede_x86_64_crypt_blk_3way) * %rdx: src (3 blocks) */ - pushq %rbp; pushq %rbx; pushq %r12; pushq %r13; pushq %r14; pushq %r15; + pushq %rsi /* dst */ + /* load input */ movl 0 * 4(%rdx), RL0d; movl 1 * 4(%rdx), RR0d; @@ -520,6 +523,7 @@ ENTRY(des3_ede_x86_64_crypt_blk_3way) bswapl RR2d; bswapl RL2d; + popq %rsi /* dst */ movl RR0d, 0 * 4(%rsi); movl RL0d, 1 * 4(%rsi); movl RR1d, 2 * 4(%rsi); @@ -532,7 +536,6 @@ ENTRY(des3_ede_x86_64_crypt_blk_3way) popq %r13; popq %r12; popq %rbx; - popq %rbp; ret; ENDPROC(des3_ede_x86_64_crypt_blk_3way) -- 2.20.1