diff options
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 8 | ||||
| -rw-r--r-- | arch/arm64/kernel/hw_breakpoint.c | 3 |
2 files changed, 10 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index d9ca1f2c0ea8..829fa6d3e561 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -21,6 +21,7 @@ /* * User space memory access functions */ +#include <linux/bitops.h> #include <linux/string.h> #include <linux/thread_info.h> @@ -103,6 +104,13 @@ static inline void set_fs(mm_segment_t fs) flag; \ }) +/* + * When dealing with data aborts, watchpoints, or instruction traps we may end + * up with a tagged userland pointer. Clear the tag to get a sane pointer to + * pass on to access_ok(), for instance. + */ +#define untagged_addr(addr) sign_extend64(addr, 55) + #define access_ok(type, addr, size) __range_ok(addr, size) #define user_addr_max get_fs diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index b45c95d34b83..eeebfc315526 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -35,6 +35,7 @@ #include <asm/traps.h> #include <asm/cputype.h> #include <asm/system_misc.h> +#include <asm/uaccess.h> /* Breakpoint currently in use for each BRP. */ static DEFINE_PER_CPU(struct perf_event *, bp_on_reg[ARM_MAX_BRP]); @@ -690,7 +691,7 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr, /* Check if the watchpoint value matches. */ val = read_wb_reg(AARCH64_DBG_REG_WVR, i); - if (val != (addr & ~alignment_mask)) + if (val != (untagged_addr(addr) & ~alignment_mask)) goto unlock; /* Possible match, check the byte address select to confirm. */ |