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ARM: fix is_gate_vma() when CONFIG_KUSER_HELPERS is enabled

PATCH New Marc Zyngier 2 participants 4 messages Aug 5, 2013 Arm (32-bit)

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Marc Zyngier

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#0 lore raw

PATCH 1/1 ARM: fix is_gate_vma() when CONFIG_KUSER_HELPERS is enabled

Commit a5463cd34354 (ARM: make vectors page inaccessible from userspace) introduced the is_gate_vma() facility to identify the vectors page, but a typo broke the /proc/<pid>/maps output:

[...]

b6ef4000-b6f0b000 r-xp 00000000 00:0c 3953760    /lib/arm-linux-gnueabi/ld-2.15.so
b6f0d000-b6f11000 rw-p 00000000 00:00 0          [vectors]
b6f11000-b6f12000 r-xp 00000000 00:00 0          [vectors]
b6f12000-b6f13000 r--p 00016000 00:0c 3953760    /lib/arm-linux-gnueabi/ld-2.15.so
b6f13000-b6f14000 rw-p 00017000 00:0c 3953760    /lib/arm-linux-gnueabi/ld-2.15.so
be886000-be8a7000 rw-p 00000000 00:00 0          [vectors]
ffff0000-ffff1000 r-xp 00000000 00:00 0          [vectors]

[...]

With the fix in place, it now reads (different run, hence the slightly different output):

[...]
b6fb1000-b6fc8000 r-xp 00000000 00:0c 3953760 /lib/arm-linux-gnueabi/ld-2.15.so
b6fca000-b6fce000 rw-p 00000000 00:00 0

b6fce000-b6fcf000 r-xp 00000000 00:00 0          [sigpage]
b6fcf000-b6fd0000 r--p 00016000 00:0c 3953760    /lib/arm-linux-gnueabi/ld-2.15.so
b6fd0000-b6fd1000 rw-p 00017000 00:0c 3953760    /lib/arm-linux-gnueabi/ld-2.15.so
bea41000-bea62000 rw-p 00000000 00:00 0          [stack]
ffff0000-ffff1000 r-xp 00000000 00:00 0          [vectors]

[...]

Cc Russell King <[email protected]>
Signed-off-by Marc Zyngier <[email protected]>
---
 arch/arm/kernel/process.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm/kernel/process.c +1 -1
index 536c85f..94f6b05 100644
@@ -462,7 +462,7 @@ int in_gate_area_no_mm(unsigned long addr)
 {
 	return in_gate_area(NULL, addr);
 }
-#define is_gate_vma(vma)	((vma) = &gate_vma)
+#define is_gate_vma(vma)	((vma) == &gate_vma)
 #else
 #define is_gate_vma(vma)	0
 #endif
Signature · 1 line
1.8.2.3
#1 lore raw

PATCH 1/1 ARM: fix is_gate_vma() when CONFIG_KUSER_HELPERS is enabled

Quoted 3 lines · Marc Zyngier

Commit a5463cd34354 (ARM: make vectors page inaccessible from userspace) introduced the is_gate_vma() facility to identify the vectors page, but a typo broke the /proc/<pid>/maps output:

Known about, and between myself and Linus we elected not to fix it for rc4. You're not the first to report it, and it will get fixed, just not as a high priority.

author
#2 lore raw

PATCH 1/1 ARM: fix is_gate_vma() when CONFIG_KUSER_HELPERS is enabled

Quoted 8 lines · Russell King - ARM Linux
Quoted 3 lines · Marc Zyngier

Commit a5463cd34354 (ARM: make vectors page inaccessible from userspace) introduced the is_gate_vma() facility to identify the vectors page, but a typo broke the /proc/<pid>/maps output:

Known about, and between myself and Linus we elected not to fix it for rc4. You're not the first to report it, and it will get fixed, just not as a high priority.

Indeed, it is only cosmetic. As long as you're aware of it, that's is good enough for me.

Thanks,

	M.
Signature · 1 line
Jazz is not dead. It just smells funny...
#3 lore raw

PATCH 1/1 ARM: fix is_gate_vma() when CONFIG_KUSER_HELPERS is enabled

Quoted 6 lines · Marc Zyngier
Quoted 5 lines · Russell King - ARM Linux
Quoted 3 lines · Marc Zyngier

Commit a5463cd34354 (ARM: make vectors page inaccessible from userspace) introduced the is_gate_vma() facility to identify the vectors page, but a typo broke the /proc/<pid>/maps output:

Quoted 6 lines
Quoted 3 lines

Known about, and between myself and Linus we elected not to fix it for rc4. You're not the first to report it, and it will get fixed, just not as a high priority.

Indeed, it is only cosmetic. As long as you're aware of it, that's is good enough for me.

Well, that cockup is on twitter, and you're not the first to send this exact patch.