bpf, x86: fix freeing of not-finalized bpf_prog_pack
In the Linux kernel, the following vulnerability has been resolved: bpf, x86: fix freeing of not-finalized bpf_prog_pack syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile() on each sub program. And then, we call it on each sub program again. jit_data is not freed in the first call of bpf_int_jit_compile(). Similarly we don't call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile(). If bpf_int_jit_compile() failed for one sub program, we will call bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a chance to call it for other sub programs. Then we will hit "goto out_free" in jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got bpf_jit_binary_pack_finalize() yet. At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is freed erroneously. Fix this with a custom bpf_jit_free() for x86_64, which calls bpf_jit_binary_pack_finalize() if necessary. Also, with custom bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more, remove it. [1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f [2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445
CVE-2022-50168
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2022-50168
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "1022a5498f6f745c3b5fd3f050a5e11e7ca354f0",
"lessThan": "f91ce608a79c0db3e72bd63c23e011a9ebc31505",
"versionType": "git"
},
{
"status": "affected",
"version": "1022a5498f6f745c3b5fd3f050a5e11e7ca354f0",
"lessThan": "60e66074812dde9cde3d99cdd3caa9e40f1a4516",
"versionType": "git"
},
{
"status": "affected",
"version": "1022a5498f6f745c3b5fd3f050a5e11e7ca354f0",
"lessThan": "1d5f82d9dd477d5c66e0214a68c3e4f308eadd6d",
"versionType": "git"
}
],
"programFiles": [
"arch/x86/net/bpf_jit_comp.c",
"include/linux/bpf.h",
"include/linux/filter.h",
"kernel/bpf/core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.18"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.18",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.18.18",
"versionType": "semver",
"lessThanOrEqual": "5.18.*"
},
{
"status": "unaffected",
"version": "5.19.2",
"versionType": "semver",
"lessThanOrEqual": "5.19.*"
},
{
"status": "unaffected",
"version": "6.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"arch/x86/net/bpf_jit_comp.c",
"include/linux/bpf.h",
"include/linux/filter.h",
"kernel/bpf/core.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2022-50168
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #30203 · Revision 1
- Added to Heist Feed
- Publisher date