{"id":"CVE-2022-49648","state":"PUBLISHED","title":"tracing/histograms: Fix memory leak problem","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/histograms: Fix memory leak problem\n\nThis reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac.\n\nAs commit 46bbe5c671e0 (\"tracing: fix double free\") said, the\n\"double free\" problem reported by clang static analyzer is:\n  > In parse_var_defs() if there is a problem allocating\n  > var_defs.expr, the earlier var_defs.name is freed.\n  > This free is duplicated by free_var_defs() which frees\n  > the rest of the list.\n\nHowever, if there is a problem allocating N-th var_defs.expr:\n  + in parse_var_defs(), the freed 'earlier var_defs.name' is\n    actually the N-th var_defs.name;\n  + then in free_var_defs(), the names from 0th to (N-1)-th are freed;\n\n                        IF ALLOCATING PROBLEM HAPPENED HERE!!! -+\n                                                                 \\\n                                                                  |\n          0th           1th                 (N-1)-th      N-th    V\n          +-------------+-------------+-----+-------------+-----------\nvar_defs: | name | expr | name | expr | ... | name | expr | name | ///\n          +-------------+-------------+-----+-------------+-----------\n\nThese two frees don't act on same name, so there was no \"double free\"\nproblem before. Conversely, after that commit, we get a \"memory leak\"\nproblem because the above \"N-th var_defs.name\" is not freed.\n\nIf enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th\nvar_defs.expr allocated, then execute on shell like:\n  $ echo 'hist:key=call_site:val=$v1,$v2:v1=bytes_req,v2=bytes_alloc' > \\\n/sys/kernel/debug/tracing/events/kmem/kmalloc/trigger\n\nThen kmemleak reports:\n  unreferenced object 0xffff8fb100ef3518 (size 8):\n    comm \"bash\", pid 196, jiffies 4295681690 (age 28.538s)\n    hex dump (first 8 bytes):\n      76 31 00 00 b1 8f ff ff                          v1......\n    backtrace:\n      [<0000000038fe4895>] kstrdup+0x2d/0x60\n      [<00000000c99c049a>] event_hist_trigger_parse+0x206f/0x20e0\n      [<00000000ae70d2cc>] trigger_process_regex+0xc0/0x110\n      [<0000000066737a4c>] event_trigger_write+0x75/0xd0\n      [<000000007341e40c>] vfs_write+0xbb/0x2a0\n      [<0000000087fde4c2>] ksys_write+0x59/0xd0\n      [<00000000581e9cdf>] do_syscall_64+0x3a/0x80\n      [<00000000cf3b065c>] entry_SYSCALL_64_after_hwframe+0x46/0xb0","publishedAt":"2025-02-26T02:23:52.035Z","updatedAt":"2026-05-23T15:22:38.887Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"240dd5118a9e0454f280ffeae63f22bd14735733","status":"affected","lessThan":"eb622d5580b9e2ff694f62da6410618bd73853cb","versionType":"git"},{"version":"e92c490f104993cea35e5f5d5108ac12df1850ac","status":"affected","lessThan":"ecc6dec12c33aa92c086cd702af9f544ddaf3c75","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"78a1400c42ee11197eb1f0f85ba51df9a4fdfff0","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"22eeff55679d9e7c0f768c79bfbd83e2f8142d89","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"4d453eb5e1eec89971aa5b3262857ee26cfdffd3","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"7edc3945bdce9c39198a10d6129377a5c53559c2","versionType":"git"},{"version":"e3a23511638a3dcf0275c1e71a46d1ca2e2e6788","status":"affected","versionType":"git"},{"version":"4.19.149","status":"affected","lessThan":"4.19.253","versionType":"semver"},{"version":"5.4.69","status":"affected","lessThan":"5.4.207","versionType":"semver"},{"version":"5.8.13","status":"affected","lessThan":"5.9","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"4.19.253","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.207","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.132","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.56","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.18.13","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]}],"references":["https://git.kernel.org/stable/c/eb622d5580b9e2ff694f62da6410618bd73853cb","https://git.kernel.org/stable/c/ecc6dec12c33aa92c086cd702af9f544ddaf3c75","https://git.kernel.org/stable/c/78a1400c42ee11197eb1f0f85ba51df9a4fdfff0","https://git.kernel.org/stable/c/22eeff55679d9e7c0f768c79bfbd83e2f8142d89","https://git.kernel.org/stable/c/4d453eb5e1eec89971aa5b3262857ee26cfdffd3","https://git.kernel.org/stable/c/7edc3945bdce9c39198a10d6129377a5c53559c2"],"weaknesses":["CWE-401"],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/49xxx/CVE-2022-49648.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-49648","state":"PUBLISHED","datePublished":"2025-02-26T02:23:52.035Z","dateUpdated":"2026-05-23T15:22:38.887Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-02-26T02:21:30.432Z"},"containers":{"cna":{"title":"tracing/histograms: Fix memory leak problem","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/histograms: Fix memory leak problem\n\nThis reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac.\n\nAs commit 46bbe5c671e0 (\"tracing: fix double free\") said, the\n\"double free\" problem reported by clang static analyzer is:\n  > In parse_var_defs() if there is a problem allocating\n  > var_defs.expr, the earlier var_defs.name is freed.\n  > This free is duplicated by free_var_defs() which frees\n  > the rest of the list.\n\nHowever, if there is a problem allocating N-th var_defs.expr:\n  + in parse_var_defs(), the freed 'earlier var_defs.name' is\n    actually the N-th var_defs.name;\n  + then in free_var_defs(), the names from 0th to (N-1)-th are freed;\n\n                        IF ALLOCATING PROBLEM HAPPENED HERE!!! -+\n                                                                 \\\n                                                                  |\n          0th           1th                 (N-1)-th      N-th    V\n          +-------------+-------------+-----+-------------+-----------\nvar_defs: | name | expr | name | expr | ... | name | expr | name | ///\n          +-------------+-------------+-----+-------------+-----------\n\nThese two frees don't act on same name, so there was no \"double free\"\nproblem before. Conversely, after that commit, we get a \"memory leak\"\nproblem because the above \"N-th var_defs.name\" is not freed.\n\nIf enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th\nvar_defs.expr allocated, then execute on shell like:\n  $ echo 'hist:key=call_site:val=$v1,$v2:v1=bytes_req,v2=bytes_alloc' > \\\n/sys/kernel/debug/tracing/events/kmem/kmalloc/trigger\n\nThen kmemleak reports:\n  unreferenced object 0xffff8fb100ef3518 (size 8):\n    comm \"bash\", pid 196, jiffies 4295681690 (age 28.538s)\n    hex dump (first 8 bytes):\n      76 31 00 00 b1 8f ff ff                          v1......\n    backtrace:\n      [<0000000038fe4895>] kstrdup+0x2d/0x60\n      [<00000000c99c049a>] event_hist_trigger_parse+0x206f/0x20e0\n      [<00000000ae70d2cc>] trigger_process_regex+0xc0/0x110\n      [<0000000066737a4c>] event_trigger_write+0x75/0xd0\n      [<000000007341e40c>] vfs_write+0xbb/0x2a0\n      [<0000000087fde4c2>] ksys_write+0x59/0xd0\n      [<00000000581e9cdf>] do_syscall_64+0x3a/0x80\n      [<00000000cf3b065c>] entry_SYSCALL_64_after_hwframe+0x46/0xb0"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"240dd5118a9e0454f280ffeae63f22bd14735733","status":"affected","lessThan":"eb622d5580b9e2ff694f62da6410618bd73853cb","versionType":"git"},{"version":"e92c490f104993cea35e5f5d5108ac12df1850ac","status":"affected","lessThan":"ecc6dec12c33aa92c086cd702af9f544ddaf3c75","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"78a1400c42ee11197eb1f0f85ba51df9a4fdfff0","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"22eeff55679d9e7c0f768c79bfbd83e2f8142d89","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"4d453eb5e1eec89971aa5b3262857ee26cfdffd3","versionType":"git"},{"version":"46bbe5c671e06f070428b9be142cc4ee5cedebac","status":"affected","lessThan":"7edc3945bdce9c39198a10d6129377a5c53559c2","versionType":"git"},{"version":"e3a23511638a3dcf0275c1e71a46d1ca2e2e6788","status":"affected","versionType":"git"},{"version":"4.19.149","status":"affected","lessThan":"4.19.253","versionType":"semver"},{"version":"5.4.69","status":"affected","lessThan":"5.4.207","versionType":"semver"},{"version":"5.8.13","status":"affected","lessThan":"5.9","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"4.19.253","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.207","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.132","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.56","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.18.13","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/eb622d5580b9e2ff694f62da6410618bd73853cb"},{"url":"https://git.kernel.org/stable/c/ecc6dec12c33aa92c086cd702af9f544ddaf3c75"},{"url":"https://git.kernel.org/stable/c/78a1400c42ee11197eb1f0f85ba51df9a4fdfff0"},{"url":"https://git.kernel.org/stable/c/22eeff55679d9e7c0f768c79bfbd83e2f8142d89"},{"url":"https://git.kernel.org/stable/c/4d453eb5e1eec89971aa5b3262857ee26cfdffd3"},{"url":"https://git.kernel.org/stable/c/7edc3945bdce9c39198a10d6129377a5c53559c2"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-23T15:22:38.887Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.149","versionEndExcluding":"4.19.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.69","versionEndExcluding":"5.4.207"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.10.132"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.15.56"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.18.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2022-49648","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:33:48.167860Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-401","lang":"en","type":"CWE","description":"CWE-401 Missing Release of Memory after Effective Lifetime"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:36:48.613Z"}}]}}}