{"id":"CVE-2026-98380","state":"PUBLISHED","title":"net/sched: reject IDR error pointers when deleting actions","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: reject IDR error pointers when deleting actions\n\ntcf_action_delete() drops the reference held by its lookup before calling\ntcf_idr_delete_index() with the saved action index.  An unlocked\nclassifier can remove that action and reserve the same IDR slot with\nERR_PTR(-EBUSY) in between.\n\ntcf_idr_delete_index() only checks the lookup result for NULL.  It\ntherefore treats the reservation as a tc_action and dereferences\ntcfa_bindcnt.  A hardware execution breakpoint was used to schedule the\ninterleaving without changing the kernel source.  KASAN reported this\ndecoded trace:\n\n  BUG: KASAN: null-ptr-deref in tca_action_gd+0x5b9/0x1010\n  Read of size 4 at addr 0000000000000010 by task poc/150\n  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002\n  RIP: tca_action_gd+0x5c0/0x1010:\n    arch_atomic_read at arch/x86/include/asm/atomic.h:23\n    raw_atomic_read at include/linux/atomic/atomic-arch-fallback.h:457\n    atomic_read at include/linux/atomic/atomic-instrumented.h:33\n    tcf_idr_delete_index at net/sched/act_api.c:766\n    tcf_action_delete at net/sched/act_api.c:1859\n    tcf_del_notify at net/sched/act_api.c:2014\n    tca_action_gd at net/sched/act_api.c:2064\n  R13: 0000000000000010 R15: fffffffffffffff0\n  Kernel panic - not syncing: Fatal exception\n\nR15 contains ERR_PTR(-EBUSY), and adding the tcfa_bindcnt offset produces\nthe address in R13.  With the guard applied, the same reproducer returned\n-ENOENT without a KASAN report or panic.  Treat error pointers as absent\nand return -ENOENT.","publishedAt":"2026-10-09T07:34:20.218Z","updatedAt":"2026-10-19T09:18:31.007Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"39b751a210bf61a374afa82749afc7a77a08bf1d","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"dd80a7519824b72c8fcfd3cc50cb93f7e2d90923","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"6bf076258aac4e0af69ef317656c31ce6444d647","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"6c9f07bf8800171de2cd3f02815cebe1f4d45f2d","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"259caa711b7688365676442e2fdb286b8aceaa80","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"968550a439f64bd1a6c0d88efb92e4f082f84a26","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"a9551f26287debe6d8aa6e8841974661065b975f","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"c82b797abe668d0b668601a93ba2c0b071a63574","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_api.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_api.c"]}],"references":["https://git.kernel.org/stable/c/39b751a210bf61a374afa82749afc7a77a08bf1d","https://git.kernel.org/stable/c/dd80a7519824b72c8fcfd3cc50cb93f7e2d90923","https://git.kernel.org/stable/c/6bf076258aac4e0af69ef317656c31ce6444d647","https://git.kernel.org/stable/c/6c9f07bf8800171de2cd3f02815cebe1f4d45f2d","https://git.kernel.org/stable/c/259caa711b7688365676442e2fdb286b8aceaa80","https://git.kernel.org/stable/c/968550a439f64bd1a6c0d88efb92e4f082f84a26","https://git.kernel.org/stable/c/a9551f26287debe6d8aa6e8841974661065b975f","https://git.kernel.org/stable/c/c82b797abe668d0b668601a93ba2c0b071a63574"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98380.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98380","state":"PUBLISHED","datePublished":"2026-10-09T07:34:20.218Z","dateUpdated":"2026-10-19T09:18:31.007Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.345Z"},"containers":{"cna":{"title":"net/sched: reject IDR error pointers when deleting actions","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: reject IDR error pointers when deleting actions\n\ntcf_action_delete() drops the reference held by its lookup before calling\ntcf_idr_delete_index() with the saved action index.  An unlocked\nclassifier can remove that action and reserve the same IDR slot with\nERR_PTR(-EBUSY) in between.\n\ntcf_idr_delete_index() only checks the lookup result for NULL.  It\ntherefore treats the reservation as a tc_action and dereferences\ntcfa_bindcnt.  A hardware execution breakpoint was used to schedule the\ninterleaving without changing the kernel source.  KASAN reported this\ndecoded trace:\n\n  BUG: KASAN: null-ptr-deref in tca_action_gd+0x5b9/0x1010\n  Read of size 4 at addr 0000000000000010 by task poc/150\n  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002\n  RIP: tca_action_gd+0x5c0/0x1010:\n    arch_atomic_read at arch/x86/include/asm/atomic.h:23\n    raw_atomic_read at include/linux/atomic/atomic-arch-fallback.h:457\n    atomic_read at include/linux/atomic/atomic-instrumented.h:33\n    tcf_idr_delete_index at net/sched/act_api.c:766\n    tcf_action_delete at net/sched/act_api.c:1859\n    tcf_del_notify at net/sched/act_api.c:2014\n    tca_action_gd at net/sched/act_api.c:2064\n  R13: 0000000000000010 R15: fffffffffffffff0\n  Kernel panic - not syncing: Fatal exception\n\nR15 contains ERR_PTR(-EBUSY), and adding the tcfa_bindcnt offset produces\nthe address in R13.  With the guard applied, the same reproducer returned\n-ENOENT without a KASAN report or panic.  Treat error pointers as absent\nand return -ENOENT."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"39b751a210bf61a374afa82749afc7a77a08bf1d","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"dd80a7519824b72c8fcfd3cc50cb93f7e2d90923","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"6bf076258aac4e0af69ef317656c31ce6444d647","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"6c9f07bf8800171de2cd3f02815cebe1f4d45f2d","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"259caa711b7688365676442e2fdb286b8aceaa80","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"968550a439f64bd1a6c0d88efb92e4f082f84a26","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"a9551f26287debe6d8aa6e8841974661065b975f","versionType":"git"},{"version":"0190c1d452a91c38a3462abdd81752be1b9006a8","status":"affected","lessThan":"c82b797abe668d0b668601a93ba2c0b071a63574","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_api.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_api.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/39b751a210bf61a374afa82749afc7a77a08bf1d"},{"url":"https://git.kernel.org/stable/c/dd80a7519824b72c8fcfd3cc50cb93f7e2d90923"},{"url":"https://git.kernel.org/stable/c/6bf076258aac4e0af69ef317656c31ce6444d647"},{"url":"https://git.kernel.org/stable/c/6c9f07bf8800171de2cd3f02815cebe1f4d45f2d"},{"url":"https://git.kernel.org/stable/c/259caa711b7688365676442e2fdb286b8aceaa80"},{"url":"https://git.kernel.org/stable/c/968550a439f64bd1a6c0d88efb92e4f082f84a26"},{"url":"https://git.kernel.org/stable/c/a9551f26287debe6d8aa6e8841974661065b975f"},{"url":"https://git.kernel.org/stable/c/c82b797abe668d0b668601a93ba2c0b071a63574"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:18:31.007Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.10.271"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.15.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.1.189"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"6.18.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"7.2.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}