The following commit has been merged into the x86/sev branch of tip:
Commit-ID: f2df15639e44d23bf82a86a03092472c7278cd39
Gitweb: https://git.kernel.org/tip/f2df15639e44d23bf82a86a03092472c7278cd39
Author: Joerg Roedel <jroedel@xxxxxxx>
AuthorDate: Wed, 19 May 2021 15:52:49 +02:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Tue, 15 Jun 2021 11:24:21 +02:00
x86/insn-eval: Make 0 a valid RIP for insn_get_effective_ip()
In theory, 0 is a valid value for the instruction pointer so don't use
it as the error return value from insn_get_effective_ip().
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20210614135327.9921-5-joro@xxxxxxxxxx
---
arch/x86/lib/insn-eval.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index a67afd7..4eecb9c 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -1417,7 +1417,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs)
}
}
-static unsigned long insn_get_effective_ip(struct pt_regs *regs)
+static int insn_get_effective_ip(struct pt_regs *regs, unsigned long *ip)
{
unsigned long seg_base = 0;
@@ -1430,10 +1430,12 @@ static unsigned long insn_get_effective_ip(struct pt_regs *regs)
if (!user_64bit_mode(regs)) {
seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS);
if (seg_base == -1L)
- return 0;
+ return -EINVAL;
}
- return seg_base + regs->ip;
+ *ip = seg_base + regs->ip;
+
+ return 0;
}
/**
@@ -1455,8 +1457,7 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE])
unsigned long ip;
int not_copied;
- ip = insn_get_effective_ip(regs);
- if (!ip)
+ if (insn_get_effective_ip(regs, &ip))
return 0;
not_copied = copy_from_user(buf, (void __user *)ip, MAX_INSN_SIZE);
@@ -1484,8 +1485,7 @@ int insn_fetch_from_user_inatomic(struct pt_regs *regs, unsigned char buf[MAX_IN
unsigned long ip;
int not_copied;
- ip = insn_get_effective_ip(regs);
- if (!ip)
+ if (insn_get_effective_ip(regs, &ip))
return 0;
not_copied = __copy_from_user_inatomic(buf, (void __user *)ip, MAX_INSN_SIZE);
|