diff options
| author | Kirill A. Shutemov | 2023-08-09 17:46:00 +0300 |
|---|---|---|
| committer | Linus Torvalds | 2023-08-09 08:05:23 -0700 |
| commit | 22883973244b1caaa26f9c6171a41ba843c8d4bd (patch) | |
| tree | 125495296da587957fde03d6f3a6dabdc85258d0 | |
| parent | 77245f1c3c6495521f6a3af082696ee2f8ce3921 (diff) | |
mm: Fix access_remote_vm() regression on tagged addresses
GDB uses /proc/PID/mem to access memory of the target process. GDB
doesn't untag addresses manually, but relies on kernel to do the right
thing.
mem_rw() of procfs uses access_remote_vm() to get data from the target
process. It worked fine until recent changes in __access_remote_vm()
that now checks if there's VMA at target address using raw address.
Untag the address before looking up the VMA.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Christina Schimpe <christina.schimpe@intel.com>
Fixes: eee9c708cc89 ("gup: avoid stack expansion warning for known-good case")
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/memory.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/memory.c b/mm/memory.c index 603b2f419948..1ec1ef3418bf 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5705,6 +5705,9 @@ int __access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, if (mmap_read_lock_killable(mm)) return 0; + /* Untag the address before looking up the VMA */ + addr = untagged_addr_remote(mm, addr); + /* Avoid triggering the temporary warning in __get_user_pages */ if (!vma_lookup(mm, addr) && !expand_stack(mm, addr)) return 0; |