In the Linux kernel, the following vulnerability has been resolved:
sysv: don’t call sb_bread() with pointers_lock held
syzbot is reporting sleep in atomic context in SysV filesystem [1], for
sb_bread() is called with rw_spinlock held.
A “write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock” bug
and a “sb_bread() with write_lock(&pointers_lock)” bug were introduced by
“Replace BKL for chain locking with sysvfs-private rwlock” in Linux 2.5.12.
Then, “[PATCH] err1-40: sysvfs locking fix” in Linux 2.6.8 fixed the
former bug by moving pointers_lock lock to the callers, but instead
introduced a “sb_bread() with read_lock(&pointers_lock)” bug (which made
this problem easier to hit).
Al Viro suggested that why not to do like get_branch()/get_block()/
find_shared() in Minix filesystem does. And doing like that is almost a
revert of “[PATCH] err1-40: sysvfs locking fix” except that get_branch()
from with find_shared() is called without write_lock(&pointers_lock).
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "13b33feb2ebd",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "1b4fe801b5be",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "674c1c4229e7",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "fd203d2c671b",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "53cb1e52c9db",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "89e8524135a3",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "a69224223746",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f4",
"lessThan": "f123dc86388c",
"versionType": "git"
}
],
"programFiles": [
"fs/sysv/itree.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "unaffected",
"version": "4.19.312",
"versionType": "custom",
"lessThanOrEqual": "4.19.*"
},
{
"status": "unaffected",
"version": "5.4.274",
"versionType": "custom",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.215",
"versionType": "custom",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.155",
"versionType": "custom",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.86",
"versionType": "custom",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.27",
"versionType": "custom",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.8.6",
"versionType": "custom",
"lessThanOrEqual": "6.8.*"
},
{
"status": "unaffected",
"version": "6.9",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/sysv/itree.c"
],
"defaultStatus": "affected"
}
]
git.kernel.org/stable/c/13b33feb2ebddc2b1aa607f553566b18a4af1d76
git.kernel.org/stable/c/1b4fe801b5bedec2b622ddb18e5c9bf26c63d79f
git.kernel.org/stable/c/53cb1e52c9db618c08335984d1ca80db220ccf09
git.kernel.org/stable/c/674c1c4229e743070e09db63a23442950ff000d1
git.kernel.org/stable/c/89e8524135a3902e7563a5a59b7b5ec1bf4904ac
git.kernel.org/stable/c/a69224223746ab96d43e5db9d22d136827b7e2d3
git.kernel.org/stable/c/f123dc86388cb669c3d6322702dc441abc35c31e
git.kernel.org/stable/c/fd203d2c671bdee9ab77090ff394d3b71b627927
lists.debian.org/debian-lts-announce/2024/06/msg00017.html
lists.debian.org/debian-lts-announce/2024/06/msg00020.html