From 0b6ad02b33448c0b8b6fdd781dffad329d1f0f7d Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sat, 11 Jan 2025 22:57:02 +0800 Subject: [PATCH] x86-64: Cast __rseq_offset to long long int [BZ #32543] commit 494d65129ed5ae1154b75cc189bbdde5e9ecf1df Author: Michael Jeanson Date: Thu Aug 1 10:35:34 2024 -0400 nptl: Introduce for RSEQ_* accessors added things like asm volatile ("movl %%fs:%P1(%q2),%0" \ : "=r" (__value) \ : "i" (offsetof (struct rseq_area, member)), \ "r" (__rseq_offset)); \ But this doesn't work for x32 when __rseq_offset is negative since the address is computed as FS + 32-bit to 64-bit zero extension of __rseq_offset + offsetof (struct rseq_area, member) Cast __rseq_offset to long long int "r" ((long long int) __rseq_offset)); \ to sign-extend 32-bit __rseq_offset to 64-bit. This is a no-op for x86-64 since x86-64 __rseq_offset is 64-bit. This fixes BZ #32543. Signed-off-by: H.J. Lu Reviewed-by: Florian Weimer --- sysdeps/x86_64/nptl/rseq-access.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/sysdeps/x86_64/nptl/rseq-access.h b/sysdeps/x86_64/nptl/rseq-access.h index 535e36281f..bc966b2972 100644 --- a/sysdeps/x86_64/nptl/rseq-access.h +++ b/sysdeps/x86_64/nptl/rseq-access.h @@ -27,18 +27,18 @@ asm volatile ("movb %%fs:%P2(%q3),%b0" \ : "=q" (__value) \ : "0" (0), "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ else if (sizeof (__value) == 4) \ asm volatile ("movl %%fs:%P1(%q2),%0" \ : "=r" (__value) \ : "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ else /* 8 */ \ { \ asm volatile ("movq %%fs:%P1(%q2),%q0" \ : "=r" (__value) \ : "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ } \ __value; }) @@ -56,12 +56,12 @@ asm volatile ("movb %b0,%%fs:%P1(%q2)" : \ : "iq" (value), \ "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ else if (sizeof (RSEQ_SELF()->member) == 4) \ asm volatile ("movl %0,%%fs:%P1(%q2)" : \ : IMM_MODE (value), \ "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ else /* 8 */ \ { \ /* Since movq takes a signed 32-bit immediate or a register source \ @@ -70,7 +70,7 @@ asm volatile ("movq %q0,%%fs:%P1(%q2)" : \ : "er" ((uint64_t) cast_to_integer (value)), \ "i" (offsetof (struct rseq_area, member)), \ - "r" (__rseq_offset)); \ + "r" ((long long int) __rseq_offset)); \ }}) /* Set member of the RSEQ area directly. */