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| author | Dan Rosenberg <drosenberg@vsecurity.com> | 2011-07-25 17:11:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-07-25 20:57:07 -0700 |
| commit | 0d0138ebe24b94065580bd2601f8bb7eb6152f56 (patch) | |
| tree | 13ab981dbddd25b57bb821394d0a3c78bf8fb25a | |
| parent | 67db392d1124e14684e23deb572de2a63b9b3b69 (diff) | |
| download | linux-0d0138ebe24b94065580bd2601f8bb7eb6152f56.tar.gz linux-0d0138ebe24b94065580bd2601f8bb7eb6152f56.tar.bz2 linux-0d0138ebe24b94065580bd2601f8bb7eb6152f56.zip | |
xtensa: prevent arbitrary read in ptrace
Prevent an arbitrary kernel read. Check the user pointer with access_ok()
before copying data in.
[akpm@linux-foundation.org: s/EIO/EFAULT/]
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: Christian Zankel <chris@zankel.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | arch/xtensa/kernel/ptrace.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c index c72c9473ef99..a0d042aa2967 100644 --- a/arch/xtensa/kernel/ptrace.c +++ b/arch/xtensa/kernel/ptrace.c @@ -147,6 +147,9 @@ int ptrace_setxregs(struct task_struct *child, void __user *uregs) elf_xtregs_t *xtregs = uregs; int ret = 0; + if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t))) + return -EFAULT; + #if XTENSA_HAVE_COPROCESSORS /* Flush all coprocessors before we overwrite them. */ coprocessor_flush_all(ti); |