Headline
CVE-2023-3212: gfs2: Don't deref jdesc in evict · torvalds/linux@504a10d
A NULL pointer dereference issue was found in the gfs2 file system in the Linux kernel. It occurs on corrupt gfs2 file systems when the evict code tries to reference the journal descriptor structure after it has been freed and set to NULL. A privileged local user could use this flaw to cause a kernel panic.
Commit
Permalink
Browse files
Browse the repository at this point in the history
gfs2: Don’t deref jdesc in evict
On corrupt gfs2 file systems the evict code can try to reference the journal descriptor structure, jdesc, after it has been freed and set to NULL. The sequence of events is:
init_journal() … fail_jindex: gfs2_jindex_free(sdp); <------frees journals, sets jdesc = NULL if (gfs2_holder_initialized(&ji_gh)) gfs2_glock_dq_uninit(&ji_gh); fail: iput(sdp->sd_jindex); <–references jdesc in evict_linked_inode evict() gfs2_evict_inode() evict_linked_inode() ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks); <------references the now freed/zeroed sd_jdesc pointer.
The call to gfs2_trans_begin is done because the truncate_inode_pages call can cause gfs2 events that require a transaction, such as removing journaled data (jdata) blocks from the journal.
This patch fixes the problem by adding a check for sdp->sd_jdesc to function gfs2_evict_inode. In theory, this should only happen to corrupt gfs2 file systems, when gfs2 detects the problem, reports it, then tries to evict all the system inodes it has read in up to that point.
Reported-by: Yang Lan [email protected] Signed-off-by: Bob Peterson [email protected] Signed-off-by: Andreas Gruenbacher [email protected]
- Loading branch information
Related news
Red Hat Security Advisory 2023-7077-01 - An update for kernel is now available for Red Hat Enterprise Linux 8. Issues addressed include buffer overflow, denial of service, double free, information leakage, memory leak, null pointer, out of bounds access, out of bounds write, and use-after-free vulnerabilities.
Ubuntu Security Notice 6466-1 - Hyunwoo Kim discovered that the DVB Core driver in the Linux kernel contained a race condition during device removal, leading to a use-after- free vulnerability. A physically proximate attacker could use this to cause a denial of service or possibly execute arbitrary code. Hyunwoo Kim discovered that the Technotrend/Hauppauge USB DEC driver in the Linux kernel did not properly handle device removal events. A physically proximate attacker could use this to cause a denial of service.
Ubuntu Security Notice 6396-3 - It was discovered that some AMD x86-64 processors with SMT enabled could speculatively execute instructions using a return address from a sibling thread. A local attacker could possibly use this to expose sensitive information. Daniel Moghimi discovered that some Intel Processors did not properly clear microarchitectural state after speculative execution of various instructions. A local unprivileged user could use this to obtain to sensitive information.
Ubuntu Security Notice 6396-2 - It was discovered that some AMD x86-64 processors with SMT enabled could speculatively execute instructions using a return address from a sibling thread. A local attacker could possibly use this to expose sensitive information. Daniel Moghimi discovered that some Intel Processors did not properly clear microarchitectural state after speculative execution of various instructions. A local unprivileged user could use this to obtain to sensitive information.
Ubuntu Security Notice 6417-1 - It was discovered that the eBPF implementation in the Linux kernel contained a race condition around read-only maps. A privileged attacker could use this to modify read-only maps. It was discovered that the IPv6 implementation in the Linux kernel contained a high rate of hash collisions in connection lookup table. A remote attacker could use this to cause a denial of service.
Ubuntu Security Notice 6412-1 - Hyunwoo Kim discovered that the DVB Core driver in the Linux kernel contained a race condition during device removal, leading to a use-after- free vulnerability. A physically proximate attacker could use this to cause a denial of service or possibly execute arbitrary code. Hyunwoo Kim discovered that the Technotrend/Hauppauge USB DEC driver in the Linux kernel did not properly handle device removal events. A physically proximate attacker could use this to cause a denial of service.
Ubuntu Security Notice 6396-1 - It was discovered that some AMD x86-64 processors with SMT enabled could speculatively execute instructions using a return address from a sibling thread. A local attacker could possibly use this to expose sensitive information. Daniel Moghimi discovered that some Intel Processors did not properly clear microarchitectural state after speculative execution of various instructions. A local unprivileged user could use this to obtain to sensitive information.
Ubuntu Security Notice 6388-1 - Daniel Moghimi discovered that some Intel Processors did not properly clear microarchitectural state after speculative execution of various instructions. A local unprivileged user could use this to obtain to sensitive information. Yang Lan discovered that the GFS2 file system implementation in the Linux kernel could attempt to dereference a null pointer in some situations. An attacker could use this to construct a malicious GFS2 image that, when mounted and operated on, could cause a denial of service.
Ubuntu Security Notice 6339-3 - It was discovered that the NTFS file system implementation in the Linux kernel did not properly validate MFT flags in certain situations. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could cause a denial of service. Zi Fan Tan discovered that the binder IPC implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code.
Ubuntu Security Notice 6339-2 - It was discovered that the NTFS file system implementation in the Linux kernel did not properly validate MFT flags in certain situations. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could cause a denial of service. Zi Fan Tan discovered that the binder IPC implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code.
Ubuntu Security Notice 6351-1 - It was discovered that the NTFS file system implementation in the Linux kernel did not properly validate MFT flags in certain situations. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could cause a denial of service. Zi Fan Tan discovered that the binder IPC implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code.
Ubuntu Security Notice 6350-1 - It was discovered that the NTFS file system implementation in the Linux kernel did not properly validate MFT flags in certain situations. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could cause a denial of service. Zi Fan Tan discovered that the binder IPC implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code.
Ubuntu Security Notice 6339-1 - It was discovered that the NTFS file system implementation in the Linux kernel did not properly validate MFT flags in certain situations. An attacker could use this to construct a malicious NTFS image that, when mounted and operated on, could cause a denial of service. Zi Fan Tan discovered that the binder IPC implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code.
Debian Linux Security Advisory 5480-1 - Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.
Debian Linux Security Advisory 5448-1 - Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.