FAILED: patch "[PATCH] arm64: compat: Don't pull syscall number from regs in" failed to apply to 4.19-stable tree

PATCH [email protected] 2 participants 3 messages Jan 7, 2019 – Jan 15, 2019

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Stable branch arm64

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[email protected]

author maintainer

2019-01-07 09:40 UTC #0 lore raw

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 53290432145a8eb143fe29e06e9c1465d43dc723 Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Thu, 3 Jan 2019 18:00:39 +0000
Subject: [PATCH] arm64: compat: Don't pull syscall number from regs in
arm_compat_syscall

The syscall number may have been changed by a tracer, so we should pass the actual number in from the caller instead of pulling it from the saved r7 value directly.

Cc <[email protected]>

Cc Pi-Hsun Shih <[email protected]>

Reviewed-by Dave Martin <[email protected]>

Signed-off-by Will Deacon <[email protected]>

arch/arm64/kernel/sys_compat.c +4 -5

index a79db4e485a6..bc348ab3dd6b 100644
@@ -66,12 +66,11 @@ do_compat_cache_op(unsigned long start, unsigned long end, int flags)
 /*
  * Handle all unrecognised system calls.
  */
-long compat_arm_syscall(struct pt_regs *regs)
+long compat_arm_syscall(struct pt_regs *regs, int scno)
 {
-	unsigned int no = regs->regs[7];
 	void __user *addr;
 
-	switch (no) {
+	switch (scno) {
 	/*
 	 * Flush a region from virtual address 'r0' to virtual address 'r1'
 	 * _exclusive_.  There is no alignment requirement on either address;

@@ -107,7 +106,7 @@ long compat_arm_syscall(struct pt_regs *regs)
 		 * way the calling program can gracefully determine whether
 		 * a feature is supported.
 		 */
-		if (no < __ARM_NR_COMPAT_END)
+		if (scno < __ARM_NR_COMPAT_END)
 			return -ENOSYS;
 		break;
 	}

@@ -116,6 +115,6 @@ long compat_arm_syscall(struct pt_regs *regs)
 		(compat_thumb_mode(regs) ? 2 : 4);
 
 	arm64_notify_die("Oops - bad compat syscall(2)", regs,
-			 SIGILL, ILL_ILLTRP, addr, no);
+			 SIGILL, ILL_ILLTRP, addr, scno);
 	return 0;
 }

arch/arm64/kernel/syscall.c +4 -5

index 032d22312881..5610ac01c1ec 100644
@@ -13,16 +13,15 @@
 #include <asm/thread_info.h>
 #include <asm/unistd.h>
 
-long compat_arm_syscall(struct pt_regs *regs);
-
+long compat_arm_syscall(struct pt_regs *regs, int scno);
 long sys_ni_syscall(void);
 
-asmlinkage long do_ni_syscall(struct pt_regs *regs)
+static long do_ni_syscall(struct pt_regs *regs, int scno)
 {
 #ifdef CONFIG_COMPAT
 	long ret;
 	if (is_compat_task()) {
-		ret = compat_arm_syscall(regs);
+		ret = compat_arm_syscall(regs, scno);
 		if (ret != -ENOSYS)
 			return ret;
 	}

@@ -47,7 +46,7 @@ static void invoke_syscall(struct pt_regs *regs, unsigned int scno,
 		syscall_fn = syscall_table[array_index_nospec(scno, sc_nr)];
 		ret = __invoke_syscall(regs, syscall_fn);
 	} else {
-		ret = do_ni_syscall(regs);
+		ret = do_ni_syscall(regs, scno);
 	}
 
 	regs->regs[0] = ret;

Will Deacon

Reviewed-by Dave Martin

2019-01-07 18:26 UTC #1 lore raw

Quoted 18 lines · On Mon, Jan 07, 2019 at 10:40:11AM +0100, [email protected] wrote:

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 53290432145a8eb143fe29e06e9c1465d43dc723 Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Thu, 3 Jan 2019 18:00:39 +0000
Subject: [PATCH] arm64: compat: Don't pull syscall number from regs in
arm_compat_syscall

Quoted 3 lines

The syscall number may have been changed by a tracer, so we should pass the actual number in from the caller instead of pulling it from the saved r7 value directly.

Fixed patch below. I don't think we need to consider kernels prior to 4.19.

Will

--->8

From 7e5f7c4e6fd50fe216fa53d9343141fbf1547a10 Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Thu, 3 Jan 2019 18:00:39 +0000
Subject: [PATCH] arm64: compat: Don't pull syscall number from regs in
arm_compat_syscall

Commit 53290432145a8eb143fe29e06e9c1465d43dc723 upstream.

The syscall number may have been changed by a tracer, so we should pass the actual number in from the caller instead of pulling it from the saved r7 value directly.

Cc <[email protected]> # 4.19

Cc Pi-Hsun Shih <[email protected]>

Reviewed-by Dave Martin <[email protected]>

Signed-off-by Will Deacon <[email protected]>

---
 arch/arm64/kernel/sys_compat.c | 9 ++++-----
 arch/arm64/kernel/syscall.c    | 9 ++++-----
 2 files changed, 8 insertions(+), 10 deletions(-)

arch/arm64/kernel/sys_compat.c +4 -5

index 7be666062c7c..010212d35700 100644
@@ -66,12 +66,11 @@ do_compat_cache_op(unsigned long start, unsigned long end, int flags)
 /*
  * Handle all unrecognised system calls.
  */
-long compat_arm_syscall(struct pt_regs *regs)
+long compat_arm_syscall(struct pt_regs *regs, int scno)
 {
 	siginfo_t info;
-	unsigned int no = regs->regs[7];
 
-	switch (no) {
+	switch (scno) {
 	/*
 	 * Flush a region from virtual address 'r0' to virtual address 'r1'
 	 * _exclusive_.  There is no alignment requirement on either address;

@@ -107,7 +106,7 @@ long compat_arm_syscall(struct pt_regs *regs)
 		 * way the calling program can gracefully determine whether
 		 * a feature is supported.
 		 */
-		if (no < __ARM_NR_COMPAT_END)
+		if (scno < __ARM_NR_COMPAT_END)
 			return -ENOSYS;
 		break;
 	}

@@ -119,6 +118,6 @@ long compat_arm_syscall(struct pt_regs *regs)
 	info.si_addr  = (void __user *)instruction_pointer(regs) -
 			 (compat_thumb_mode(regs) ? 2 : 4);
 
-	arm64_notify_die("Oops - bad compat syscall(2)", regs, &info, no);
+	arm64_notify_die("Oops - bad compat syscall(2)", regs, &info, scno);
 	return 0;
 }

arch/arm64/kernel/syscall.c +4 -5

index 032d22312881..5610ac01c1ec 100644
@@ -13,16 +13,15 @@
 #include <asm/thread_info.h>
 #include <asm/unistd.h>
 
-long compat_arm_syscall(struct pt_regs *regs);
-
+long compat_arm_syscall(struct pt_regs *regs, int scno);
 long sys_ni_syscall(void);
 
-asmlinkage long do_ni_syscall(struct pt_regs *regs)
+static long do_ni_syscall(struct pt_regs *regs, int scno)
 {
 #ifdef CONFIG_COMPAT
 	long ret;
 	if (is_compat_task()) {
-		ret = compat_arm_syscall(regs);
+		ret = compat_arm_syscall(regs, scno);
 		if (ret != -ENOSYS)
 			return ret;
 	}

@@ -47,7 +46,7 @@ static void invoke_syscall(struct pt_regs *regs, unsigned int scno,
 		syscall_fn = syscall_table[array_index_nospec(scno, sc_nr)];
 		ret = __invoke_syscall(regs, syscall_fn);
 	} else {
-		ret = do_ni_syscall(regs);
+		ret = do_ni_syscall(regs, scno);
 	}
 
 	regs->regs[0] = ret;

Signature · 1 line

2.11.0

Greg KH

author maintainer

2019-01-15 15:40 UTC #2 lore raw

Quoted 19 lines · Will Deacon

Quoted 18 lines · On Mon, Jan 07, 2019 at 10:40:11AM +0100, [email protected] wrote:
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 53290432145a8eb143fe29e06e9c1465d43dc723 Mon Sep 17 00:00:00 2001
From: Will Deacon <[email protected]>
Date: Thu, 3 Jan 2019 18:00:39 +0000
Subject: [PATCH] arm64: compat: Don't pull syscall number from regs in
arm_compat_syscall

Quoted 5 lines

Quoted 3 lines
The syscall number may have been changed by a tracer, so we should pass the actual number in from the caller instead of pulling it from the saved r7 value directly.
Fixed patch below. I don't think we need to consider kernels prior to 4.19.

Now applied, thanks.

greg k-h