Most recent entries from all

bdu:2025-05317

certfr-2024-avi-0363 — De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'en…

certfr-2024-avi-0363

EUVD-2026-309507

fkie_cve-2021-47044

In the Linux kernel, the following vulnerability has been resolved:

sched/fair: Fix shift-out-of-bounds in load_balance()

Syzbot reported a handful of occurrences where an sd->nr_balance_failed can grow to much higher values than one would expect.

A successful load_balance() resets it to 0; a failed one increments it. Once it gets to sd->cache_nice_tries + 3, this *should* trigger an active balance, which will either set it to sd->cache_nice_tries+1 or reset it to 0. However, in case the to-be-active-balanced task is not allowed to run on env->dst_cpu, then the increment is done without any further modification.

This could then be repeated ad nauseam, and would explain the absurdly high values reported by syzbot (86, 149). VincentG noted there is value in letting sd->cache_nice_tries grow, so the shift itself should be fixed. That means preventing:

""" If the value of the right operand is negative or is greater than or equal to the width of the promoted left operand, the behavior is undefined. """

Thus we need to cap the shift exponent to BITS_PER_TYPE(typeof(lefthand)) - 1.

I had a look around for other similar cases via coccinelle:

@expr@ position pos; expression E1; expression E2; @@ ( E1 >> E2@pos | E1 >> E2@pos )

@cst depends on expr@ position pos; expression expr.E1; constant cst; @@ ( E1 >> cst@pos | E1 << cst@pos )

@script:python depends on !cst@ pos << expr.pos; exp << expr.E2; @@ # Dirty hack to…

GHSA-8g29-7ww6-62wf

In the Linux kernel, the following vulnerability has been resolved:

sched/fair: Fix shift-out-of-bounds in load_balance()

Syzbot reported a handful of occurrences where an sd->nr_balance_failed can grow to much higher values than one would expect.

""" If the value of the right operand is negative or is greater than or equal to the width of the promoted left operand, the behavior is undefined. """

Thus we need to cap the shift exponent to BITS_PER_TYPE(typeof(lefthand)) - 1.

I had a look around for other similar cases via coccinelle:

@expr@ position pos; expression E1; expression E2; @@ ( E1 >> E2@pos | E1 >> E2@pos )

@cst depends on expr@ position pos; expression expr.E1; constant cst; @@ ( E1 >> cst@pos | E1 << cst@pos )

@script:python depends on !cst@ pos << expr.pos; exp << expr.E2; @@ # Dirty hack to…

gsd-2021-47044

SUSE-SU-2024:1465-1 — Security update for the Linux Kernel

Security update for the Linux Kernel

UBUNTU-CVE-2021-47044

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 53 more

In the Linux kernel, the following vulnerability has been resolved: sched/fair: Fix shift-out-of-bounds in load_balance() Syzbot reported a handful of occurrences where an sd->nr_balance_failed can grow to much higher values than one would expect. A successful load_balance() resets it to 0; a failed one increments it. Once it gets to sd->cache_nice_tries + 3, this *should* trigger an active balance, which will either set it to sd->cache_nice_tries+1 or reset it to 0. However, in case the to-be-active-balanced task is not allowed to run on env->dst_cpu, then the increment is done without any further modification. This could then be repeated ad nauseam, and would explain the absurdly high values reported by syzbot (86, 149). VincentG noted there is value in letting sd->cache_nice_tries grow, so the shift itself should be fixed. That means preventing: """ If the value of the right operand is negative or is greater than or equal to the width of the promoted left operand, the behavior is undefined. """ Thus we need to cap the shift exponent to BITS_PER_TYPE(typeof(lefthand)) - 1. I had a look around for other similar cases via coccinelle: @expr@ position pos; expression E1; expression E2; @@ ( E1 >> E2@pos | E1 >> E2@pos ) @cst depends on expr@ position pos; expression expr.E1; constant cst; @@ ( E1 >> cst@pos | E1 << cst@pos ) @script:python depends on !cst@ pos << expr.pos; exp << expr.E2; @@ # Dirty hack to ignore con…

WID-SEC-W-2024-0499 — Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff

Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.