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| author | Richard Weinberger <richard@nod.at> | 2015-08-09 23:26:33 +0300 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2015-10-19 23:53:37 +0300 |
| commit | 56b88a3bf97a39d3f4f010509917b76a865a6dc8 (patch) | |
| tree | 408b519405bd8545f8da4102ac120db58d2a1f3e /arch/um/kernel/trap.c | |
| parent | 6b1873371cea13036171d03a7c1e3e59158b4505 (diff) | |
| download | linux-56b88a3bf97a39d3f4f010509917b76a865a6dc8.tar.xz | |
um: Fix kernel mode fault condition
We have to exclude memory locations <= PAGE_SIZE from
the condition and let the kernel mode fault path catch it.
Otherwise a kernel NULL pointer exception will be reported
as a kernel user space access.
Fixes: d2313084e2c (um: Catch unprotected user memory access)
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/kernel/trap.c')
| -rw-r--r-- | arch/um/kernel/trap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index d8a9fce6ee2e..98783dd0fa2e 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -220,7 +220,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, show_regs(container_of(regs, struct pt_regs, regs)); panic("Segfault with no mm"); } - else if (!is_user && address < TASK_SIZE) { + else if (!is_user && address > PAGE_SIZE && address < TASK_SIZE) { show_regs(container_of(regs, struct pt_regs, regs)); panic("Kernel tried to access user memory at addr 0x%lx, ip 0x%lx", address, ip); |