IT

Tracker / CVE-2024-50273

CVE-2024-50273

High 7.8

In the Linux kernel, the following vulnerability has been resolved: btrfs: reinitialize delayed ref list after deleting it from the list At insert_delayed_ref() if we need to update the action of an existing ref to BTRFS_DROP_DELAYED_REF, we delete the ref from its ref head's ref_add_list using list_del(), which leaves the ref's add_list member not reinitialized, as list_del() sets the next and prev members of the list to LIST_POISON1 and LIST_POISON2, respectively. If later we end up calling drop_delayed_ref() against the ref, which can happen during merging or when destroying delayed refs due to a transaction abort, we can trigger a crash since at drop_delayed_ref() we call list_empty() against the ref's add_list, which returns false since the list was not reinitialized after the list_del() and as a consequence we call list_del() again at drop_delayed_ref(). This results in an invalid list access since the next and prev members are set to poison pointers, resulting in a splat if CONFIG_LIST_HARDENED and CONFIG_DEBUG_LIST are set or invalid poison pointer dereferences otherwise. So fix this by deleting from the list with list_del_init() instead.

Affected products and versions

linux linux_kernel
linux linux_kernel · 4.10 → 4.19.324
linux linux_kernel · 4.20 → 5.4.286
linux linux_kernel · 5.11 → 5.15.172
linux linux_kernel · 5.16 → 6.1.117
linux linux_kernel · 5.5 → 5.10.230
linux linux_kernel · 6.2 → 6.6.61
linux linux_kernel · 6.7 → 6.11.8

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References