diff options
| author | Keith Owens <kaos@sgi.com> | 2007-06-26 16:25:22 +1000 |
|---|---|---|
| committer | Tony Luck <tony.luck@intel.com> | 2007-06-26 13:33:10 -0700 |
| commit | 66fa9b107e259d01929fe647796b3021d3a83c4a (patch) | |
| tree | 6fe7bde9c86a4d5dffae53ab815b34362eb19571 /arch | |
| parent | 9be26f4c4b138c425598bd3cc50411bd87fce287 (diff) | |
| download | linux-66fa9b107e259d01929fe647796b3021d3a83c4a.tar.gz linux-66fa9b107e259d01929fe647796b3021d3a83c4a.tar.bz2 linux-66fa9b107e259d01929fe647796b3021d3a83c4a.zip | |
[IA64] Correct unwind validation code
Both rp_loc and pfs_loc can be in the register stack area _or_ they can
be in the memory stack area, the latter occurs when a struct pt_regs is
pushed. Correct the validation check on these fields to check for both
stack areas. Not allowing for memory stack locations means no
backtrace past ia64_leave_kernel, or any other code that uses
PT_REGS_UNWIND_INFO.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/ia64/kernel/unwind.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/ia64/kernel/unwind.c b/arch/ia64/kernel/unwind.c index b0b08b5f3eca..c1bdb5131814 100644 --- a/arch/ia64/kernel/unwind.c +++ b/arch/ia64/kernel/unwind.c @@ -1856,11 +1856,19 @@ find_save_locs (struct unw_frame_info *info) return 0; } +static int +unw_valid(const struct unw_frame_info *info, unsigned long* p) +{ + unsigned long loc = (unsigned long)p; + return (loc >= info->regstk.limit && loc < info->regstk.top) || + (loc >= info->memstk.top && loc < info->memstk.limit); +} + int unw_unwind (struct unw_frame_info *info) { unsigned long prev_ip, prev_sp, prev_bsp; - unsigned long ip, pr, num_regs, rp_loc, pfs_loc; + unsigned long ip, pr, num_regs; STAT(unsigned long start, flags;) int retval; @@ -1871,8 +1879,7 @@ unw_unwind (struct unw_frame_info *info) prev_bsp = info->bsp; /* validate the return IP pointer */ - rp_loc = (unsigned long) info->rp_loc; - if ((rp_loc < info->regstk.limit) || (rp_loc > info->regstk.top)) { + if (!unw_valid(info, info->rp_loc)) { /* FIXME: should really be level 0 but it occurs too often. KAO */ UNW_DPRINT(1, "unwind.%s: failed to locate return link (ip=0x%lx)!\n", __FUNCTION__, info->ip); @@ -1888,8 +1895,7 @@ unw_unwind (struct unw_frame_info *info) } /* validate the previous stack frame pointer */ - pfs_loc = (unsigned long) info->pfs_loc; - if ((pfs_loc < info->regstk.limit) || (pfs_loc > info->regstk.top)) { + if (!unw_valid(info, info->pfs_loc)) { UNW_DPRINT(0, "unwind.%s: failed to locate ar.pfs!\n", __FUNCTION__); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; |